color_space.inl

 
 
namespace glm{
namespace detail
{
    template<length_t L, typename T, qualifier Q>
    struct compute_rgbToSrgb
    {
        GLM_FUNC_QUALIFIER static vec<L, T, Q> call(vec<L, T, Q> const& ColorRGB, T GammaCorrection)
        {
            vec<L, T, Q> const ClampedColor(clamp(ColorRGB, static_cast<T>(0), static_cast<T>(1)));
 
            return mix(
                pow(ClampedColor, vec<L, T, Q>(GammaCorrection)) * static_cast<T>(1.055) - static_cast<T>(0.055),
                ClampedColor * static_cast<T>(12.92),
                lessThan(ClampedColor, vec<L, T, Q>(static_cast<T>(0.0031308))));
        }
    };
 
    template<typename T, qualifier Q>
    struct compute_rgbToSrgb<4, T, Q>
    {
        GLM_FUNC_QUALIFIER static vec<4, T, Q> call(vec<4, T, Q> const& ColorRGB, T GammaCorrection)
        {
            return vec<4, T, Q>(compute_rgbToSrgb<3, T, Q>::call(vec<3, T, Q>(ColorRGB), GammaCorrection), ColorRGB.w);
        }
    };
 
    template<length_t L, typename T, qualifier Q>
    struct compute_srgbToRgb
    {
        GLM_FUNC_QUALIFIER static vec<L, T, Q> call(vec<L, T, Q> const& ColorSRGB, T Gamma)
        {
            return mix(
                pow((ColorSRGB + static_cast<T>(0.055)) * static_cast<T>(0.94786729857819905213270142180095), vec<L, T, Q>(Gamma)),
                ColorSRGB * static_cast<T>(0.07739938080495356037151702786378),
                lessThanEqual(ColorSRGB, vec<L, T, Q>(static_cast<T>(0.04045))));
        }
    };
 
    template<typename T, qualifier Q>
    struct compute_srgbToRgb<4, T, Q>
    {
        GLM_FUNC_QUALIFIER static vec<4, T, Q> call(vec<4, T, Q> const& ColorSRGB, T Gamma)
        {
            return vec<4, T, Q>(compute_srgbToRgb<3, T, Q>::call(vec<3, T, Q>(ColorSRGB), Gamma), ColorSRGB.w);
        }
    };
}//namespace detail
 
    template<length_t L, typename T, qualifier Q>
    GLM_FUNC_QUALIFIER vec<L, T, Q> convertLinearToSRGB(vec<L, T, Q> const& ColorLinear)
    {
        return detail::compute_rgbToSrgb<L, T, Q>::call(ColorLinear, static_cast<T>(0.41666));
    }
 
    // Based on Ian Taylor http://chilliant.blogspot.fr/2012/08/srgb-approximations-for-hlsl.html
    template<>
    GLM_FUNC_QUALIFIER vec<3, float, lowp> convertLinearToSRGB(vec<3, float, lowp> const& ColorLinear)
    {
        vec<3, float, lowp> S1 = sqrt(ColorLinear);
        vec<3, float, lowp> S2 = sqrt(S1);
        vec<3, float, lowp> S3 = sqrt(S2);
        return 0.662002687f * S1 + 0.684122060f * S2 - 0.323583601f * S3 - 0.0225411470f * ColorLinear;
    }
 
    template<length_t L, typename T, qualifier Q>
    GLM_FUNC_QUALIFIER vec<L, T, Q> convertLinearToSRGB(vec<L, T, Q> const& ColorLinear, T Gamma)
    {
        return detail::compute_rgbToSrgb<L, T, Q>::call(ColorLinear, static_cast<T>(1) / Gamma);
    }
 
    template<length_t L, typename T, qualifier Q>
    GLM_FUNC_QUALIFIER vec<L, T, Q> convertSRGBToLinear(vec<L, T, Q> const& ColorSRGB)
    {
        return detail::compute_srgbToRgb<L, T, Q>::call(ColorSRGB, static_cast<T>(2.4));
    }
 
    template<length_t L, typename T, qualifier Q>
    GLM_FUNC_QUALIFIER vec<L, T, Q> convertSRGBToLinear(vec<L, T, Q> const& ColorSRGB, T Gamma)
    {
        return detail::compute_srgbToRgb<L, T, Q>::call(ColorSRGB, Gamma);
    }
}//namespace glm