finish parser, modify files

9 files changed, 5084 insertions, 9 deletions

diff --git a/circuitpython/frozen/circuitpython-stage/docs/README.rst b/circuitpython/frozen/circuitpython-stage/docs/README.rst
index 89a0106..dfadce4 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/docs/README.rst
+++ b/circuitpython/frozen/circuitpython-stage/docs/README.rst
@@ -1 +1,44 @@
-../README.rst
\ No newline at end of file
+Stage – a Tile and Sprite Engine
+********************************
+
+Stage is a library that lets you display tile grids and sprites on SPI-based
+RGB displays in CircuitPython. It is mostly made with video games in mind, but
+it can be useful in making any kind of graphical user interface too.
+
+For performance reasons, a part of this library has been written in C and has
+to be compiled as part of the CircuitPython firmware as the ``_stage`` module.
+For memory saving reasons, it's best if this library is also included in the
+firmware, as a frozen module.
+
+
+API Reference
+*************
+
+The API reference is available at `<http://circuitpython-stage.readthedocs.io>`_.
+
+stage
+=====
+.. automodule:: stage
+   :members:
+
+
+ugame
+=======
+.. module:: ugame
+
+.. data:: display
+
+    An initialized display, that can be used for creating Stage objects.
+
+.. data:: buttons
+
+    An instance of ``GamePad`` or other similar class, that has a
+    ``get_pressed`` method for retrieving a bit mask of pressed buttons. That
+    value can be then checked with & operator against the constants: ``K_UP``,
+    ``K_DOWN``, ``K_LEFT``, ``K_RIGHT``, ``K_X``, ``K_O`` and on some platforms
+    also: ``K_START`` and ``K_SELECT``.
+
+.. data:: audio
+
+    And instance of the ``Audio`` or other similar class, that has ``play``,
+    ``stop`` and ``mute`` methods.
diff --git a/circuitpython/frozen/circuitpython-stage/feather_m4_minitft_featherwing/stage.py b/circuitpython/frozen/circuitpython-stage/feather_m4_minitft_featherwing/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/feather_m4_minitft_featherwing/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/feather_m4_minitft_featherwing/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)
diff --git a/circuitpython/frozen/circuitpython-stage/itsybitsy_m4_express/stage.py b/circuitpython/frozen/circuitpython-stage/itsybitsy_m4_express/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/itsybitsy_m4_express/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/itsybitsy_m4_express/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)
diff --git a/circuitpython/frozen/circuitpython-stage/meowbit/stage.py b/circuitpython/frozen/circuitpython-stage/meowbit/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/meowbit/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/meowbit/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)
diff --git a/circuitpython/frozen/circuitpython-stage/pewpew_m4/stage.py b/circuitpython/frozen/circuitpython-stage/pewpew_m4/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/pewpew_m4/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/pewpew_m4/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)
diff --git a/circuitpython/frozen/circuitpython-stage/picosystem/stage.py b/circuitpython/frozen/circuitpython-stage/picosystem/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/picosystem/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/picosystem/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)
diff --git a/circuitpython/frozen/circuitpython-stage/pybadge/stage.py b/circuitpython/frozen/circuitpython-stage/pybadge/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/pybadge/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/pybadge/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)
diff --git a/circuitpython/frozen/circuitpython-stage/pygamer/stage.py b/circuitpython/frozen/circuitpython-stage/pygamer/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/pygamer/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/pygamer/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)
diff --git a/circuitpython/frozen/circuitpython-stage/ugame10/stage.py b/circuitpython/frozen/circuitpython-stage/ugame10/stage.py
index 2dedc93..44ab69a 120000..100644
--- a/circuitpython/frozen/circuitpython-stage/ugame10/stage.py
+++ b/circuitpython/frozen/circuitpython-stage/ugame10/stage.py
@@ -1 +1,630 @@
-../stage.py
\ No newline at end of file
+import time
+import array
+import digitalio
+import struct
+
+import _stage
+
+
+FONT = (b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'P\x01\xd4\x05\xf5\x17\xed\x1e\xd5\x15\xd0\x01P\x01\x00\x00'
+          b'P\x01\xd0\x01\xd5\x15\xed\x1e\xf5\x17\xd4\x05P\x01\x00\x00'
+          b'P\x01\xd0\x05\x95\x17\xfd\x1f\x95\x17\xd0\x05P\x01\x00\x00'
+          b'P\x01\xd4\x01\xb5\x15\xfd\x1f\xb5\x15\xd4\x01P\x01\x00\x00'
+          b'T\x05\xf9\x1b\xdd\x1d}\x1f\xd9\x19\xa9\x1aT\x05\x00\x00'
+          b'T\x05\xf9\x1b]\x1d\xdd\x1dY\x19\xa9\x1aT\x05\x00\x00P\x01\xd0\x01'
+          b'\xe5\x16\xfd\x1f\xe4\x06t\x07\x14\x05\x00\x00P\x01\xd5\x15'
+          b']\x1d\x95\x15\xf4\x07\xe4\x06T\x05\x00\x00\x14\x05y\x1b'
+          b'\xfd\x1f\xf9\x1b\xe4\x06\xd0\x01@\x00\x00\x00P\x01\xf4\x06'
+          b'\xad\x1b\xed\x1b\xf9\x1a\xa4\x06P\x01\x00\x00@U\xd0\xff'
+          b'\xf4\xaa\xbdV\xad\x01m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00'
+          b'm\x00m\x00m\x00m\x00m\x00\xbd\x01\xf9V\xe4\xff\x90\xaa@UUU\xff\xff'
+          b'\xaa\xaaUU\x00\x00\x00\x00\x00\x00\x00\x00U\x01\xff\x06'
+          b'\xea\x1b\x95o@n\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m\x00m'
+          b'\x00m\x00m\x00m\x00m\x00m@o\xd5k\xff\x1a\xaa\x06U\x01'
+          b'\x00\x00\x00\x00\x00\x00\x00\x00UU\xff\xff\xaa\xaaUU'
+          b'\x00\x00\x00\x00\x00UE\xfe\xd9\xef\xdd\x9f\xad\x9f\xad\x9a'
+          b'\x00\x00\x00\x00\x00\x00U\x15\xf7o\xa7jW\x15v\x00\xadu\xed\xda'
+          b'\xddv\x99\xe6E\x9a\x00U\x00\x00\x00\x00m\x00W\x00n\x00\x15\x00'
+          b'\x1b\x00\x05\x00\x00\x00\x00\x00\xaa\x00\xaa\x00\xaa\x00\xaa\x00'
+          b'\x00\xaa\x00\xaa\x00\xaa\x00\xaaP\x05\x94\x16\xa4\x1b\xe4\x1b'
+          b'\xe4\x1a\xa4\x1aT\x15\x00\x00P\x00\xd0\x01\xd0\x07\xd4\x19'
+          b'\xf9\x1d\xbd\x05T\x00\x00\x00T\x05\xf5\x17\xdd\x1d\xdd\x1d'
+          b'\xf5\x17\xe4\x06T\x05\x00\x00\x14\x05e\x16y\x1b\xd4\x05y\x1be\x16'
+          b'\x14\x05\x00\x00T\x15\xf5\x1f\x9d\x19\xf5\x1d\xd4\x1d\xd0\x1d'
+          b'P\x15\x00\x00\x00\x00P\x01\xe4\x06\xf4\x07\xe4\x06P\x01'
+          b'\x00\x00\x00\x00U\x15\xdd\x1d\xdd\x1d\x99\x19U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00U\x15\xdd\x1d'
+          b'U\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01\xd0\x01\x90\x01P\x01\xd0\x01'
+          b'P\x01\x00\x00T\x05t\x07d\x06T\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x14\x05u\x17\xed\x1et\x07\xed\x1eu\x17\x14\x05\x00\x00'
+          b'T\x15\xf5\x1b\x99\x05\xf5\x17\x94\x19\xf9\x17U\x05\x00\x00'
+          b'\x15\x14\x1d\x1dU\x07\xd0\x01t\x15\x1d\x1d\x05\x15\x00\x00'
+          b'T\x01\xe4\x05u\x07\xdd\x01]\x17\xe5\x1dT\x14\x00\x00P\x01\xd0\x01'
+          b'\x90\x01P\x01\x00\x00\x00\x00\x00\x00\x00\x00@\x05P\x06'
+          b'\x90\x01\xd0\x01\x90\x01P\x06@\x05\x00\x00T\x00d\x01'
+          b'\x90\x01\xd0\x01\x90\x01d\x01T\x00\x00\x00\x00\x00\x14\x05'
+          b't\x07\xd0\x01t\x07\x14\x05\x00\x00\x00\x00P\x01\x90\x01'
+          b'\xd5\x15\xf9\x1b\xd5\x15\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00P\x01\xd0\x01\x90\x01P\x01\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'\x00\x00\x00\x00P\x01\xd0\x01P\x01\x00\x00\x00\x04\x00\x1d'
+          b'@\x07\xd0\x01t\x00\x1d\x00\x04\x00\x00\x00T\x05\xe5\x16'
+          b'Y\x1a\xdd\x1di\x19\xe5\x16T\x05\x00\x00@\x01\xd0\x01'
+          b'\xe4\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00T\x05\xf9\x17'
+          b'U\x1d\xf4\x17Y\x05\xfd\x1fU\x15\x00\x00T\x05\xf5\x17]\x1d\x94\x07'
+          b']\x1d\xf5\x17T\x05\x00\x00P\x00t\x00]\x05]\x17\xfd\x1fU\x17'
+          b'@\x05\x00\x00U\x15\xfd\x1b]\x05\xfd\x1bU\x1d\xf9\x1bU\x05\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xfd\x1b]\x1d\xf9\x1bT\x05\x00\x00U\x15\xfd\x1f'
+          b'U\x19\xd0\x06d\x01t\x00T\x00\x00\x00T\x05\xf5\x17]\x1d\xf5\x17'
+          b']\x1d\xf5\x17T\x05\x00\x00T\x05\xf9\x1b]\x1d\xf9\x1fT\x1d\xf9\x17'
+          b'U\x05\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01P\x01'
+          b'\x00\x00\x00\x00\x00\x00P\x01\xd0\x01P\x01\xd0\x01\x90\x01'
+          b'P\x01\x00\x00\x00\x05@\x07\xd0\x01t\x00\xd0\x01@\x07'
+          b'\x00\x05\x00\x00\x00\x00U\x15\xf9\x1bT\x05\xf9\x1bU\x15'
+          b'\x00\x00\x00\x00\x14\x00t\x00\xd0\x01@\x07\xd0\x01t\x00'
+          b'\x14\x00\x00\x00T\x05\xe5\x17]\x1d\xd5\x16P\x05\xd0\x01'
+          b'P\x01\x00\x00T\x05\xb5\x17\xdd\x1d\x9d\x1bY\x15\xf5\x06'
+          b'T\x05\x00\x00P\x00\xe4\x01Y\x07]\x1d\xed\x1e]\x1d\x15\x15\x00\x00'
+          b'U\x01\xfd\x05]\x07\xed\x16]\x1d\xfd\x17U\x05\x00\x00T\x05\xf5\x06'
+          b']\x01\x1d\x14]\x1d\xf5\x17T\x05\x00\x00U\x01\xbd\x05]\x17\x1d\x1d'
+          b']\x1d\xfd\x16U\x05\x00\x00U\x05\xfd\x06]\x01\xfd\x01]\x15\xfd\x1b'
+          b'U\x15\x00\x00U\x15\xfd\x1b]\x15]\x00\xbd\x01]\x01\x15\x00\x00\x00'
+          b'T\x15\xf5\x1b]\x05\xdd\x1fY\x1d\xf5\x1bT\x15\x00\x00'
+          b'\x15\x15\x1d\x1d]\x1d\xfd\x1f]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'T\x05\xe4\x06\xd0\x01\xd0\x01\xd0\x01\xe4\x06T\x05\x00\x00'
+          b'\x00\x15\x00\x1d\x00\x1d\x05\x1d]\x19\xf5\x17T\x05\x00\x00'
+          b'\x15\x14\x1d\x1d]\x07\xfd\x01]\x07\x1d\x1d\x15\x14\x00\x00'
+          b'\x15\x00\x1d\x00\x1d\x00\x1d\x00]\x15\xfd\x1fU\x15\x00\x00'
+          b'\x05\x14\x1d\x1dm\x1e\xdd\x1d]\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x05\x15\x1d\x1dm\x1d\xdd\x1d]\x1e\x1d\x1d\x15\x14\x00\x00'
+          b'T\x01\xb5\x05]\x17\x1d\x1d]\x1d\xe5\x17T\x05\x00\x00U\x05\xfd\x16'
+          b']\x19]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x01\xb5\x05]\x17\x1d\x1d'
+          b']\x1e\xe5\x07T\x1d\x00\x15U\x05\xfd\x16]\x19]\x1d\xfd\x07]\x1d'
+          b'\x15\x15\x00\x00T\x05\xf5\x07]\x01\xe5\x06T\x1d\xf9\x17'
+          b'U\x05\x00\x00U\x15\xf9\x1b\xd5\x15\xd0\x01\xd0\x01\xd0\x01'
+          b'P\x01\x00\x00\x15\x15\x1d\x1d\x1d\x1d\x19\x1du\x19\xd4\x17'
+          b'P\x05\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17d\x06\xd0\x01'
+          b'@\x00\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xd9\x19u\x17'
+          b'\x14\x05\x00\x00\x05\x14\x1d\x1dt\x07\xd0\x01t\x07\x1d\x1d'
+          b'\x05\x14\x00\x00\x15\x15\x1d\x1d\x19\x19u\x17\x94\x05\xd0\x01'
+          b'P\x01\x00\x00U\x15\xf9\x1bU\x07\xd0\x01t\x15\xf9\x1bU\x15\x00\x00'
+          b'T\x05\xf4\x06t\x01t\x00t\x01\xf4\x06T\x05\x00\x00\x05\x00\x1d\x00'
+          b't\x00\xd0\x01@\x07\x00\x1d\x00\x14\x00\x00T\x05\xe4\x07P\x07@\x07'
+          b'P\x07\xe4\x07T\x05\x00\x00@\x00\xd0\x01t\x07\x19\x19'
+          b'\x04\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+          b'U\x15\xf9\x1bU\x15\x00\x00P\x00\xb4\x01\xd4\x06P\x07@\x01\x00\x00'
+          b'\x00\x00\x00\x00\x00\x00T\x15\xe5\x1f]\x1d]\x1d\xf5\x1f'
+          b'T\x15\x00\x00\x15\x00]\x05\xfd\x16]\x1d]\x1d\xfd\x17U\x05\x00\x00'
+          b'\x00\x00T\x05\xe5\x07]\x05]\x1d\xf5\x16T\x05\x00\x00\x00\x15T\x1d'
+          b'\xe5\x1f]\x1d]\x1d\xf5\x1fT\x15\x00\x00\x00\x00T\x05'
+          b'\xf5\x17\xad\x1e]\x15\xf5\x07T\x05\x00\x00@\x15P\x1e'
+          b'\xd4\x15\xf4\x07\xd4\x05\xd0\x01\xd0\x01P\x01\x00\x00T\x15'
+          b'\xe5\x1f]\x1d\xf5\x1fT\x1d\xf9\x16U\x05\x15\x00]\x05\xfd\x16]\x1d'
+          b'\x1d\x1d\x1d\x1d\x15\x15\x00\x00P\x01\xd0\x01P\x01\xd0\x01'
+          b'\xd0\x01\xd0\x01P\x01\x00\x00@\x05@\x07@\x05@\x07E\x07]\x07'
+          b'\xe5\x05T\x01\x15\x00\x1d\x14]\x1d\xfd\x06]\x19\x1d\x1d'
+          b'\x15\x14\x00\x00T\x00t\x00t\x00t\x00d\x05\xd4\x07P\x05\x00\x00'
+          b'\x00\x00U\x05\xfd\x17\xdd\x19\xdd\x1d]\x1d\x15\x15\x00\x00'
+          b'\x00\x00U\x05\xfd\x17]\x19\x1d\x1d\x1d\x1d\x15\x15\x00\x00'
+          b'\x00\x00T\x05\xe5\x17]\x1d]\x1d\xf5\x17T\x05\x00\x00\x00\x00U\x05'
+          b'\xfd\x17]\x1d]\x1d\xfd\x17]\x05\x15\x00\x00\x00T\x15\xf5\x1f]\x1d'
+          b']\x1d\xf5\x1fT\x1d\x00\x15\x00\x00U\x05\xdd\x16}\x1d]\x04\x1d\x00'
+          b'\x15\x00\x00\x00\x00\x00T\x15\xe5\x1f\xad\x05\x94\x1e\xfd\x16'
+          b'U\x05\x00\x00T\x00u\x05\xfd\x07t\x01t\x01\xd4\x07P\x05\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d\x1d\x1d]\x1d\xe5\x1fT\x15\x00\x00'
+          b'\x00\x00\x05\x14\x1d\x1d\x19\x19u\x17\xd4\x05P\x01\x00\x00'
+          b'\x00\x00\x15\x15]\x1d\xdd\x1d\xd9\x19u\x17T\x05\x00\x00'
+          b'\x00\x00\x15\x15m\x1e\xd4\x05\xd4\x05m\x1e\x15\x15\x00\x00'
+          b'\x00\x00\x15\x15\x1d\x1d]\x1d\xe5\x1fT\x1d\xfd\x17U\x05'
+          b'\x00\x00U\x15\xfd\x1f\xa4\x15\x95\x06\xfd\x1fU\x15\x00\x00'
+          b'@\x05\x90\x07\xd0\x01t\x01\xd0\x01\x90\x07@\x05\x00\x00'
+          b'P\x01\x90\x01\xd0\x01\xd0\x01\xd0\x01\x90\x01P\x01\x00\x00'
+          b'T\x00\xb4\x01\xd0\x01P\x07\xd0\x01\xb4\x01T\x00\x00\x00'
+          b'\x00\x00T\x00u\x15\xd9\x19U\x17@\x05\x00\x00\x00\x00U\x15\xfd\x1f'
+          b'\xed\x1e\xbd\x1f\xed\x1e\xfd\x1fU\x15\x00\x00')
+
+PALETTE = (b'\xf8\x1f\x00\x00\xcey\xff\xff\xf8\x1f\x00\x19\xfc\xe0\xfd\xe0'
+           b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+
+
+def color565(r, g, b):
+    """Convert 24-bit RGB color to 16-bit."""
+    return (r & 0xf8) << 8 | (g & 0xfc) << 3 | b >> 3
+
+
+def collide(ax0, ay0, ax1, ay1, bx0, by0, bx1=None, by1=None):
+    """Return True if the two rectangles intersect."""
+    if bx1 is None:
+        bx1 = bx0
+    if by1 is None:
+        by1 = by0
+    return not (ax1 < bx0 or ay1 < by0 or ax0 > bx1 or ay0 > by1)
+
+
+class BMP16:
+    """Read 16-color BMP files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.colors = 0
+
+    def read_header(self):
+        """Read the file's header information."""
+
+        if self.colors:
+            return
+        with open(self.filename, 'rb') as f:
+            f.seek(10)
+            self.data = int.from_bytes(f.read(4), 'little')
+            f.seek(18)
+            self.width = int.from_bytes(f.read(4), 'little')
+            self.height = int.from_bytes(f.read(4), 'little')
+            f.seek(46)
+            self.colors = int.from_bytes(f.read(4), 'little')
+
+    def read_palette(self):
+        """Read the color palette information."""
+
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data - self.colors * 4)
+            for color in range(self.colors):
+                buffer = f.read(4)
+                c = color565(buffer[2], buffer[1], buffer[0])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        """Read the image data."""
+        line_size = self.width >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+
+        with open(self.filename, 'rb') as f:
+            f.seek(self.data)
+            index = (self.height - 1) * line_size
+            for line in range(self.height):
+                chunk = f.read(line_size)
+                buffer[index:index + line_size] = chunk
+                index -= line_size
+        return buffer
+
+
+def read_blockstream(f):
+    while True:
+        size = f.read(1)[0]
+        if size == 0:
+            break
+        for i in range(size):
+            yield f.read(1)[0]
+
+
+class EndOfData(Exception):
+    pass
+
+
+class LZWDict:
+    def __init__(self, code_size):
+        self.code_size = code_size
+        self.clear_code = 1 << code_size
+        self.end_code = self.clear_code + 1
+        self.codes = []
+        self.clear()
+
+    def clear(self):
+        self.last = b''
+        self.code_len = self.code_size + 1
+        self.codes[:] = []
+
+    def decode(self, code):
+        if code == self.clear_code:
+            self.clear()
+            return b''
+        elif code == self.end_code:
+            raise EndOfData()
+        elif code < self.clear_code:
+            value = bytes([code])
+        elif code <= len(self.codes) + self.end_code:
+            value = self.codes[code - self.end_code - 1]
+        else:
+            value = self.last + self.last[0:1]
+        if self.last:
+            self.codes.append(self.last + value[0:1])
+        if (len(self.codes) + self.end_code + 1 >= 1 << self.code_len and
+            self.code_len < 12):
+                self.code_len += 1
+        self.last = value
+        return value
+
+
+def lzw_decode(data, code_size):
+    dictionary = LZWDict(code_size)
+    bit = 0
+    try:
+        byte = next(data)
+        try:
+            while True:
+                code = 0
+                for i in range(dictionary.code_len):
+                    code |= ((byte >> bit) & 0x01) << i
+                    bit += 1
+                    if bit >= 8:
+                        bit = 0
+                        byte = next(data)
+                yield dictionary.decode(code)
+        except EndOfData:
+            while True:
+                next(data)
+    except StopIteration:
+        return
+
+
+class GIF16:
+    """Read 16-color GIF files."""
+
+    def __init__(self, filename):
+        self.filename = filename
+
+    def read_header(self):
+        with open(self.filename, 'rb') as f:
+            header = f.read(6)
+            if header not in {b'GIF87a', b'GIF89a'}:
+                raise ValueError("Not GIF file")
+            self.width, self.height, flags, self.background, self.aspect = (
+                struct.unpack('<HHBBB', f.read(7)))
+            self.palette_size = 1 << ((flags & 0x07) + 1)
+        if not flags & 0x80:
+            raise NotImplementedError()
+        if self.palette_size > 16:
+            raise ValueError("Too many colors (%d/16)." % self.palette_size)
+
+    def read_palette(self):
+        palette = array.array('H', (0 for i in range(16)))
+        with open(self.filename, 'rb') as f:
+            f.seek(13)
+            for color in range(self.palette_size):
+                buffer = f.read(3)
+                c = color565(buffer[0], buffer[1], buffer[2])
+                palette[color] = ((c << 8) | (c >> 8)) & 0xffff
+        return palette
+
+    def read_data(self, buffer=None):
+        line_size = (self.width + 1) >> 1
+        if buffer is None:
+            buffer = bytearray(line_size * self.height)
+        with open(self.filename, 'rb') as f:
+            f.seek(13 + self.palette_size * 3)
+            while True: # skip to first frame
+                block_type = f.read(1)[0]
+                if block_type == 0x2c:
+                    break
+                elif block_type == 0x21: # skip extension
+                    extension_type = f.read(1)[0]
+                    while True:
+                        size = f.read(1)[0]
+                        if size == 0:
+                            break
+                        f.seek(1, size)
+                elif block_type == 0x3b:
+                    raise NotImplementedError()
+            x, y, w, h, flags = struct.unpack('<HHHHB', f.read(9))
+            if (flags & 0x80 or flags & 0x40 or
+                    w != self.width or h != self.height or x != 0 or y != 0):
+                raise NotImplementedError()
+            min_code_size = f.read(1)[0]
+            x = 0
+            y = 0
+            for decoded in lzw_decode(read_blockstream(f), min_code_size):
+                for pixel in decoded:
+                    if x & 0x01:
+                        buffer[(x >> 1) + y * line_size] |= pixel
+                    else:
+                        buffer[(x >> 1) + y * line_size] = pixel << 4
+                    x += 1
+                    if (x >= self.width):
+                        x = 0
+                        y += 1
+        return buffer
+
+
+class Bank:
+    """
+    Store graphics for the tiles and sprites.
+
+    A single bank stores exactly 16 tiles, each 16x16 pixels in 16 possible
+    colors, and a 16-color palette. We just like the number 16.
+
+    """
+
+    def __init__(self, buffer=None, palette=None):
+        self.buffer = buffer
+        self.palette = palette
+
+    @classmethod
+    def from_bmp16(cls, filename):
+        """Read the bank from a BMP file."""
+        return cls.from_image(filename)
+
+
+    @classmethod
+    def from_image(cls, filename):
+        """Read the bank from an image file."""
+        if filename.lower().endswith(".gif"):
+            image = GIF16(filename)
+        elif filename.lower().endswith(".bmp"):
+            image = BMP16(filename)
+        else:
+            raise ValueError("Unsupported format")
+        image.read_header()
+        if image.width != 16 or image.height != 256:
+            raise ValueError("Image size not 16x256")
+        palette = image.read_palette()
+        buffer = image.read_data()
+        return cls(buffer, palette)
+
+
+class Grid:
+    """
+    A grid is a layer of tiles that can be displayed on the screen. Each square
+    can contain any of the 16 tiles from the associated bank.
+    """
+
+    def __init__(self, bank, width=8, height=8, palette=None, buffer=None):
+        self.x = 0
+        self.y = 0
+        self.z = 0
+        self.stride = (width + 1) & 0xfe
+        self.width = width
+        self.height = height
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.buffer = buffer or bytearray((self.stride * height)>>1)
+        self.layer = _stage.Layer(self.stride, self.height, self.bank.buffer,
+                                  self.palette, self.buffer)
+
+    def tile(self, x, y, tile=None):
+        """Get or set what tile is displayed in the given place."""
+
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return 0
+        index = (y * self.stride + x) >> 1
+        b = self.buffer[index]
+        if tile is None:
+            return b & 0x0f if x & 0x01 else b >> 4
+        if x & 0x01:
+            b = b & 0xf0 | tile
+        else:
+            b = b & 0x0f | (tile << 4)
+        self.buffer[index] = b
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+
+class WallGrid(Grid):
+    """
+    A special grid, shifted from its parents by half a tile, useful for making
+    nice-looking corners of walls and similar structures.
+    """
+
+    def __init__(self, grid, walls, bank, palette=None):
+        super().__init__(bank, grid.width + 1, grid.height + 1, palette)
+        self.grid = grid
+        self.walls = walls
+        self.update()
+        self.move(self.x - 8, self.y - 8)
+
+    def update(self):
+        for y in range(self.height):
+            for x in range(self.width):
+                t = 0
+                bit = 1
+                for dy in (-1, 0):
+                    for dx in (-1, 0):
+                        if self.grid.tile(x + dx, y + dy) in self.walls:
+                            t |= bit
+                        bit <<= 1
+                self.tile(x, y, t)
+
+
+class Sprite:
+    """
+    A sprite is a layer containing just a single tile from the associated bank,
+    that can be positioned anywhere on the screen.
+    """
+
+    def __init__(self, bank, frame, x, y, z=0, rotation=0, palette=None):
+        self.bank = bank
+        self.palette = palette or bank.palette
+        self.frame = frame
+        self.rotation = rotation
+        self.x = x
+        self.y = y
+        self.z = z
+        self.layer = _stage.Layer(1, 1, self.bank.buffer, self.palette)
+        self.layer.move(x, y)
+        self.layer.frame(frame, rotation)
+        self.px = x
+        self.py = y
+
+    def move(self, x, y, z=None):
+        """Move the sprite to the given place."""
+
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def set_frame(self, frame=None, rotation=None):
+        """
+        Set the current graphic and rotation of the sprite.
+
+        The possible values for rotation are: 0 - none, 1 - 90 degrees
+        clockwise, 2 - 180 degrees, 3 - 90 degrees counter-clockwise, 4 -
+        mirrored, 5 - 90 degrees clockwise and mirrored, 6 - 180 degrees and
+        mirrored, 7 - 90 degrees counter-clockwise and mirrored.  """
+
+        if frame is not None:
+            self.frame = frame
+        if rotation is not None:
+            self.rotation = rotation
+        self.layer.frame(self.frame, self.rotation)
+
+    def update(self):
+        pass
+
+
+class Text:
+    """Text layer. For displaying text."""
+
+    def __init__(self, width, height, font=None, palette=None, buffer=None):
+        self.width = width
+        self.height = height
+        self.font = font or FONT
+        self.palette = palette or PALETTE
+        self.buffer = buffer or bytearray(width * height)
+        self.layer = _stage.Text(width, height, self.font,
+                                 self.palette, self.buffer)
+        self.column = 0
+        self.row = 0
+        self.x = 0
+        self.y = 0
+        self.z = 0
+
+    def char(self, x, y, c=None, hightlight=False):
+        """Get or set the character at the given location."""
+        if not 0 <= x < self.width or not 0 <= y < self.height:
+            return
+        if c is None:
+            return chr(self.buffer[y * self.width + x])
+        c = ord(c)
+        if hightlight:
+            c |= 0x80
+        self.buffer[y * self.width + x] = c
+
+    def move(self, x, y, z=None):
+        """Shift the whole layer respective to the screen."""
+        self.x = x
+        self.y = y
+        if z is not None:
+            self.z = z
+        self.layer.move(int(x), int(y))
+
+    def cursor(self, x=None, y=None):
+        """Move the text cursor to the specified row and column."""
+        if y is not None:
+            self.row = min(max(0, y), self.width - 1)
+        if x is not None:
+            self.column = min(max(0, x), self.height - 1)
+
+    def text(self, text, hightlight=False):
+        """
+        Display text starting at the current cursor location.
+        Return the dimensions of the rendered text.
+        """
+        longest = 0
+        tallest = 0
+        for c in text:
+            if c != '\n':
+                self.char(self.column, self.row, c, hightlight)
+                self.column += 1
+            if self.column >= self.width or c == '\n':
+                longest = max(longest, self.column)
+                self.column = 0
+                self.row += 1
+                if self.row >= self.height:
+                    tallest = max(tallest, self.row)
+                    self.row = 0
+        longest = max(longest, self.column)
+        tallest = max(tallest, self.row) + (1 if self.column > 0 else 0)
+        return longest * 8, tallest * 8
+
+    def clear(self):
+        """Clear all text from the layer."""
+        for i in range(self.width * self.height):
+            self.buffer[i] = 0
+
+
+class Stage:
+    """
+    Represents what is being displayed on the screen.
+
+    The ``display`` parameter is displayio.Display representing an initialized
+    display connected to the device.
+
+    The ``fps`` specifies the maximum frame rate to be enforced.
+
+    The ``scale`` specifies an optional scaling up of the display, to use
+    2x2 or 3x3, etc. pixels. If not specified, it is inferred from the display
+    size (displays wider than 256 pixels will have scale=2, for example).
+    """
+    buffer = bytearray(512)
+
+    def __init__(self, display, fps=6, scale=None):
+        if scale is None:
+            self.scale = max(1, display.width // 128)
+        else:
+            self.scale = scale
+        self.layers = []
+        self.display = display
+        self.width = display.width // self.scale
+        self.height = display.height // self.scale
+        self.last_tick = time.monotonic()
+        self.tick_delay = 1 / fps
+        self.vx = 0
+        self.vy = 0
+
+    def tick(self):
+        """Wait for the start of the next frame."""
+        self.last_tick += self.tick_delay
+        wait = max(0, self.last_tick - time.monotonic())
+        if wait:
+            time.sleep(wait)
+        else:
+            self.last_tick = time.monotonic()
+
+    def render_block(self, x0=None, y0=None, x1=None, y1=None):
+        """Update a rectangle of the screen."""
+        if x0 is None:
+            x0 = self.vx
+        if y0 is None:
+            y0 = self.vy
+        if x1 is None:
+            x1 = self.width + self.vx
+        if y1 is None:
+            y1 = self.height + self.vy
+        x0 = min(max(0, x0 - self.vx), self.width - 1)
+        y0 = min(max(0, y0 - self.vy), self.height - 1)
+        x1 = min(max(1, x1 - self.vx), self.width)
+        y1 = min(max(1, y1 - self.vy), self.height)
+        if x0 >= x1 or y0 >= y1:
+            return
+        layers = [l.layer for l in self.layers]
+        _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                      self.display, self.scale, self.vx, self.vy)
+
+    def render_sprites(self, sprites):
+        """Update the spots taken by all the sprites in the list."""
+        layers = [l.layer for l in self.layers]
+        for sprite in sprites:
+            x = int(sprite.x) - self.vx
+            y = int(sprite.y) - self.vy
+            x0 = max(0, min(self.width - 1, min(sprite.px, x)))
+            y0 = max(0, min(self.height - 1, min(sprite.py, y)))
+            x1 = max(1, min(self.width, max(sprite.px, x) + 16))
+            y1 = max(1, min(self.height, max(sprite.py, y) + 16))
+            sprite.px = x
+            sprite.py = y
+            if x0 >= x1 or y0 >= y1:
+                continue
+            _stage.render(x0, y0, x1, y1, layers, self.buffer,
+                          self.display, self.scale, self.vx, self.vy)