Use gamma correct (and nearly gamma correct) color mixing
@@ -281,12 +281,21 @@ uint32_t GB_convert_rgb15(GB_gameboy_t *gb, uint16_t color, bool for_border)
if (gb->color_correction_mode != GB_COLOR_CORRECTION_CORRECT_CURVES) {
uint8_t new_r, new_g, new_b;
+ double gamma = 2.2;
+ if (gb->color_correction_mode < GB_COLOR_CORRECTION_REDUCE_CONTRAST) {
+ /* Don't use absolutely gamma-correct mixing for the high-contrast
+ modes, to prevent the blue hues from being too washed out */
+ gamma = 1.6;
+ }
+
+ // TODO: Optimze pow out using a LUT
if (agb) {
- new_g = (g * 5 + b) / 6;
+ new_g = pow((pow(g / 255.0, gamma) * 5 + pow(b / 255.0, gamma)) / 6, 1 / gamma) * 255;
}
else {
- new_g = (g * 3 + b) / 4;
+ new_g = pow((pow(g / 255.0, gamma) * 3 + pow(b / 255.0, gamma)) / 4, 1 / gamma) * 255;
}
+
new_r = r;
new_b = b;
if (gb->color_correction_mode == GB_COLOR_CORRECTION_REDUCE_CONTRAST) {
