Function promote_channel_to_hd

src/fl/gfx/colorutils.cpp.hpp:271–273

};

inline fl::u16 promote_channel_to_hd(fl::u8 channel) {
    return static_cast<fl::u16>(channel) << 8;
}

inline fl::u16 lerp_channel_to_hd(fl::u8 a, fl::u8 b, fl::u16 frac,
                                  fl::u32 segment_size) {