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-rw-r--r--shared-module/displayio/ColorConverter.c178
1 files changed, 166 insertions, 12 deletions
diff --git a/shared-module/displayio/ColorConverter.c b/shared-module/displayio/ColorConverter.c
index d20b24c01..c2c3214aa 100644
--- a/shared-module/displayio/ColorConverter.c
+++ b/shared-module/displayio/ColorConverter.c
@@ -26,16 +26,170 @@
#include "shared-bindings/displayio/ColorConverter.h"
-void common_hal_displayio_colorconverter_construct(displayio_colorconverter_t* self) {
-}
-
-bool common_hal_displayio_colorconverter_convert(displayio_colorconverter_t *self, uint32_t input_color, uint16_t* output_color) {
- // TODO(tannewt): Validate the color input against the input format.
- uint32_t r5 = (input_color >> 19);
- uint32_t g6 = (input_color >> 10) & 0x3f;
- uint32_t b5 = (input_color >> 3) & 0x1f;
- uint32_t packed = r5 << 11 | g6 << 5 | b5;
- // swap bytes
- *output_color = __builtin_bswap16(packed);
- return true;
+#include "py/misc.h"
+
+uint32_t displayio_colorconverter_dither_noise_1 (uint32_t n)
+{
+ n = (n >> 13) ^ n;
+ int nn = (n * (n * n * 60493 + 19990303) + 1376312589) & 0x7fffffff;
+ return (uint32_t) (((float)nn / (1073741824.0f*2)) * 255);
+}
+
+uint32_t displayio_colorconverter_dither_noise_2(uint32_t x, uint32_t y) {
+ return displayio_colorconverter_dither_noise_1(x + y * 0xFFFF);
+}
+
+void common_hal_displayio_colorconverter_construct(displayio_colorconverter_t* self, bool dither) {
+ self->dither = dither;
+}
+
+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;
+ return r5 << 11 | g6 << 5 | b5;
+}
+
+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;
+}
+
+uint8_t displayio_colorconverter_compute_chroma(uint32_t color_rgb888) {
+ uint32_t r8 = (color_rgb888 >> 16);
+ uint32_t g8 = (color_rgb888 >> 8) & 0xff;
+ uint32_t b8 = color_rgb888 & 0xff;
+ uint8_t max = MAX(r8, MAX(g8, b8));
+ uint8_t min = MIN(r8, MIN(g8, b8));
+ return max - min;
+}
+
+uint8_t displayio_colorconverter_compute_hue(uint32_t color_rgb888) {
+ uint32_t r8 = (color_rgb888 >> 16);
+ uint32_t g8 = (color_rgb888 >> 8) & 0xff;
+ uint32_t b8 = color_rgb888 & 0xff;
+ uint8_t max = MAX(r8, MAX(g8, b8));
+ uint8_t min = MIN(r8, MIN(g8, b8));
+ uint8_t c = max - min;
+ if (c == 0) {
+ return 0;
+ }
+
+ int32_t hue = 0;
+ if (max == r8) {
+ hue = (((int32_t) (g8 - b8) * 40) / c) % 240;
+ } else if (max == g8) {
+ hue = (((int32_t) (b8 - r8) + (2 * c)) * 40) / c;
+ } else if (max == b8) {
+ hue = (((int32_t) (r8 - g8) + (4 * c)) * 40) / c;
+ }
+ if (hue < 0) {
+ hue += 240;
+ }
+
+ return hue;
+}
+
+void displayio_colorconverter_compute_tricolor(const _displayio_colorspace_t* colorspace, uint8_t pixel_hue, uint8_t pixel_luma, uint32_t* color) {
+
+ int16_t hue_diff = colorspace->tricolor_hue - pixel_hue;
+ if ((-10 <= hue_diff && hue_diff <= 10) || hue_diff <= -220 || hue_diff >= 220) {
+ if (colorspace->grayscale) {
+ *color = 0;
+ } else {
+ *color = 1;
+ }
+ } else if (!colorspace->grayscale) {
+ *color = 0;
+ }
+}
+
+void common_hal_displayio_colorconverter_convert(displayio_colorconverter_t *self, const _displayio_colorspace_t* colorspace, uint32_t input_color, uint32_t* output_color) {
+ displayio_input_pixel_t input_pixel;
+ input_pixel.pixel = input_color;
+ input_pixel.x = input_pixel.y = input_pixel.tile = input_pixel.tile_x = input_pixel.tile_y = 0;
+
+ displayio_output_pixel_t output_pixel;
+ output_pixel.pixel = 0;
+ output_pixel.opaque = false;
+
+ displayio_colorconverter_convert(self, colorspace, &input_pixel, &output_pixel);
+
+ (*output_color) = output_pixel.pixel;
+}
+
+void common_hal_displayio_colorconverter_set_dither(displayio_colorconverter_t* self, bool dither) {
+ self->dither = dither;
+}
+
+bool common_hal_displayio_colorconverter_get_dither(displayio_colorconverter_t* self) {
+ return self->dither;
+}
+
+void displayio_colorconverter_convert(displayio_colorconverter_t *self, const _displayio_colorspace_t* colorspace, const displayio_input_pixel_t *input_pixel, displayio_output_pixel_t *output_color) {
+ uint32_t pixel = input_pixel->pixel;
+
+ if (self->dither){
+ uint8_t randr = (displayio_colorconverter_dither_noise_2(input_pixel->tile_x,input_pixel->tile_y));
+ uint8_t randg = (displayio_colorconverter_dither_noise_2(input_pixel->tile_x+33,input_pixel->tile_y));
+ uint8_t randb = (displayio_colorconverter_dither_noise_2(input_pixel->tile_x,input_pixel->tile_y+33));
+
+ uint32_t r8 = (pixel >> 16);
+ uint32_t g8 = (pixel >> 8) & 0xff;
+ uint32_t b8 = pixel & 0xff;
+
+ if (colorspace->depth == 16) {
+ b8 = MIN(255,b8 + (randb&0x07));
+ r8 = MIN(255,r8 + (randr&0x07));
+ g8 = MIN(255,g8 + (randg&0x03));
+ } else {
+ int bitmask = 0xFF >> colorspace->depth;
+ b8 = MIN(255,b8 + (randb&bitmask));
+ r8 = MIN(255,r8 + (randr&bitmask));
+ g8 = MIN(255,g8 + (randg&bitmask));
+ }
+ pixel = r8 << 16 | g8 << 8 | b8;
+ }
+
+ if (colorspace->depth == 16) {
+ uint16_t packed = displayio_colorconverter_compute_rgb565(pixel);
+ if (colorspace->reverse_bytes_in_word) {
+ // swap bytes
+ packed = __builtin_bswap16(packed);
+ }
+ output_color->pixel = packed;
+ output_color->opaque = true;
+ return;
+ } else if (colorspace->tricolor) {
+ uint8_t luma = displayio_colorconverter_compute_luma(pixel);
+ output_color->pixel = luma >> (8 - colorspace->depth);
+ if (displayio_colorconverter_compute_chroma(pixel) <= 16) {
+ if (!colorspace->grayscale) {
+ output_color->pixel = 0;
+ }
+ output_color->opaque = true;
+ return;
+ }
+ uint8_t pixel_hue = displayio_colorconverter_compute_hue(pixel);
+ displayio_colorconverter_compute_tricolor(colorspace, pixel_hue, luma, &output_color->pixel);
+ return;
+ } else if (colorspace->grayscale && colorspace->depth <= 8) {
+ uint8_t luma = displayio_colorconverter_compute_luma(pixel);
+ output_color->pixel = luma >> (8 - colorspace->depth);
+ output_color->opaque = true;
+ return;
+ }
+ output_color->opaque = false;
+}
+
+
+
+// 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) {
}