Split module into multiple files

[hackapet/Adafruit_Blinka_Displayio.git] / displayio / colorconverter.py

diff --git a/displayio/colorconverter.py b/displayio/colorconverter.py
new file mode 100644 (file)
index 0000000..3c2041f
--- /dev/null
+++ b/displayio/colorconverter.py
@@ -0,0 +1,124 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2020 Melissa LeBlanc-Williams for Adafruit Industries
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+"""
+`displayio`
+================================================================================
+
+displayio for Blinka
+
+**Software and Dependencies:**
+
+* Adafruit Blinka:
+  https://github.com/adafruit/Adafruit_Blinka/releases
+
+* Author(s): Melissa LeBlanc-Williams
+
+"""
+
+__version__ = "0.0.0-auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_Blinka_displayio.git"
+
+
+class ColorConverter:
+    """Converts one color format to another. Color converter based on original displayio
+    code for consistency.
+    """
+
+    def __init__(self, *, dither=False):
+        """Create a ColorConverter object to convert color formats.
+        Only supports rgb888 to RGB565 currently.
+        :param bool dither: Adds random noise to dither the output image
+        """
+        self._dither = dither
+        self._depth = 16
+
+    # pylint: disable=no-self-use
+    def _compute_rgb565(self, color):
+        self._depth = 16
+        return (color >> 19) << 11 | ((color >> 10) & 0x3F) << 5 | (color >> 3) & 0x1F
+
+    def _compute_luma(self, color):
+        red = color >> 16
+        green = (color >> 8) & 0xFF
+        blue = color & 0xFF
+        return (red * 19) / 255 + (green * 182) / 255 + (blue + 54) / 255
+
+    def _compute_chroma(self, color):
+        red = color >> 16
+        green = (color >> 8) & 0xFF
+        blue = color & 0xFF
+        return max(red, green, blue) - min(red, green, blue)
+
+    def _compute_hue(self, color):
+        red = color >> 16
+        green = (color >> 8) & 0xFF
+        blue = color & 0xFF
+        max_color = max(red, green, blue)
+        chroma = self._compute_chroma(color)
+        if chroma == 0:
+            return 0
+        hue = 0
+        if max_color == red:
+            hue = (((green - blue) * 40) / chroma) % 240
+        elif max_color == green:
+            hue = (((blue - red) + (2 * chroma)) * 40) / chroma
+        elif max_color == blue:
+            hue = (((red - green) + (4 * chroma)) * 40) / chroma
+        if hue < 0:
+            hue += 240
+
+        return hue
+
+    def _dither_noise_1(self, noise):
+        noise = (noise >> 13) ^ noise
+        more_noise = (
+            noise * (noise * noise * 60493 + 19990303) + 1376312589
+        ) & 0x7FFFFFFF
+        return (more_noise / (1073741824.0 * 2)) * 255
+
+    def _dither_noise_2(self, x, y):
+        return self._dither_noise_1(x + y * 0xFFFF)
+
+    def _compute_tricolor(self):
+        pass
+
+    def convert(self, color):
+        "Converts the given rgb888 color to RGB565"
+        if self._dither:
+            return color  # To Do: return a dithered color
+        return self._compute_rgb565(color)
+
+    # pylint: enable=no-self-use
+
+    @property
+    def dither(self):
+        """When true the color converter dithers the output by adding
+        random noise when truncating to display bitdepth
+        """
+        return self._dither
+
+    @dither.setter
+    def dither(self, value):
+        if not isinstance(value, bool):
+            raise ValueError("Value should be boolean")
+        self._dither = value