circuitpython/shared-module/displayio/ColorConverter.c
2019-07-19 16:11:13 -07:00

71 lines
3.0 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2018 Scott Shawcroft 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.
*/
#include "shared-bindings/displayio/ColorConverter.h"
void common_hal_displayio_colorconverter_construct(displayio_colorconverter_t* self) {
}
uint16_t displayio_colorconverter_compute_rgb565(uint32_t color_rgb888) {
uint32_t r5 = (color_rgb888 >> 19);
uint32_t g6 = (color_rgb888 >> 10) & 0x3f;
uint32_t b5 = (color_rgb888 >> 3) & 0x1f;
uint32_t packed = r5 << 11 | g6 << 5 | b5;
// swap bytes
return __builtin_bswap16(packed);
}
uint8_t displayio_colorconverter_compute_luma(uint32_t color_rgb888) {
uint32_t r8 = (color_rgb888 >> 16);
uint32_t g8 = (color_rgb888 >> 8) & 0xff;
uint32_t b8 = color_rgb888 & 0xff;
return (r8 * 19) / 255 + (g8 * 182) / 255 + (b8 + 54) / 255;
}
bool displayio_colorconverter_convert(displayio_colorconverter_t *self, const _displayio_colorspace_t* colorspace, uint32_t input_color, uint32_t* output_color) {
if (colorspace->depth == 16) {
*output_color = displayio_colorconverter_compute_rgb565(input_color);
return true;
} else if (colorspace->grayscale && colorspace->depth <= 8) {
uint8_t luma = displayio_colorconverter_compute_luma(input_color);
*output_color = luma >> (8 - colorspace->depth);
return true;
}
return false;
}
void common_hal_displayio_colorconverter_convert(displayio_colorconverter_t *self, const _displayio_colorspace_t* colorspace, uint32_t input_color, uint32_t* output_color) {
displayio_colorconverter_convert(self, colorspace, input_color, output_color);
}
// Currently no refresh logic is needed for a ColorConverter.
bool displayio_colorconverter_needs_refresh(displayio_colorconverter_t *self) {
return false;
}
void displayio_colorconverter_finish_refresh(displayio_colorconverter_t *self) {
}