src/shapes/paint/color.cpp

#include "rive/shapes/paint/color.hpp"
#include <stdio.h>

namespace rive {
    unsigned int colorARGB(int a, int r, int g, int b) {
        return (((a & 0xff) << 24) | ((r & 0xff) << 16) | ((g & 0xff) << 8) | ((b & 0xff) << 0)) &
               0xFFFFFFFF;
    }

    unsigned int colorRed(ColorInt value) { return (0x00ff0000 & value) >> 16; }

    unsigned int colorGreen(ColorInt value) { return (0x0000ff00 & value) >> 8; }

    unsigned int colorBlue(ColorInt value) { return (0x000000ff & value) >> 0; }

    unsigned int colorAlpha(ColorInt value) { return (0xff000000 & value) >> 24; }

    float colorOpacity(ColorInt value) { return (float)colorAlpha(value) / 0xFF; }

    ColorInt colorWithAlpha(ColorInt value, unsigned int a) {
        return colorARGB(a, colorRed(value), colorGreen(value), colorBlue(value));
    }

    ColorInt colorWithOpacity(ColorInt value, float opacity) {
        return colorWithAlpha(value, std::round(255.0 * opacity));
    }

    ColorInt colorModulateOpacity(ColorInt value, float opacity) {
        return colorWithAlpha(value, std::round(255.0f * colorOpacity(value) * opacity));
    }

    static unsigned int lerp(unsigned int a, unsigned int b, float mix) {
        return a * (1.0f - mix) + b * mix;
    }

    ColorInt colorLerp(ColorInt from, ColorInt to, float mix) {
        return colorARGB(lerp(colorAlpha(from), colorAlpha(to), mix),
                         lerp(colorRed(from), colorRed(to), mix),
                         lerp(colorGreen(from), colorGreen(to), mix),
                         lerp(colorBlue(from), colorBlue(to), mix));
    }
} // namespace rive