| 1 | /// @ref gtc_color_space |
| 2 | |
| 3 | namespace glm{ |
| 4 | namespace detail |
| 5 | { |
| 6 | template<length_t L, typename T, qualifier Q> |
| 7 | struct compute_rgbToSrgb |
| 8 | { |
| 9 | GLM_FUNC_QUALIFIER static vec<L, T, Q> call(vec<L, T, Q> const& ColorRGB, T GammaCorrection) |
| 10 | { |
| 11 | vec<L, T, Q> const ClampedColor(clamp(ColorRGB, static_cast<T>(0), static_cast<T>(1))); |
| 12 | |
| 13 | return mix( |
| 14 | pow(ClampedColor, vec<L, T, Q>(GammaCorrection)) * static_cast<T>(1.055) - static_cast<T>(0.055), |
| 15 | ClampedColor * static_cast<T>(12.92), |
| 16 | lessThan(ClampedColor, vec<L, T, Q>(static_cast<T>(0.0031308)))); |
| 17 | } |
| 18 | }; |
| 19 | |
| 20 | template<typename T, qualifier Q> |
| 21 | struct compute_rgbToSrgb<4, T, Q> |
| 22 | { |
| 23 | GLM_FUNC_QUALIFIER static vec<4, T, Q> call(vec<4, T, Q> const& ColorRGB, T GammaCorrection) |
| 24 | { |
| 25 | return vec<4, T, Q>(compute_rgbToSrgb<3, T, Q>::call(vec<3, T, Q>(ColorRGB), GammaCorrection), ColorRGB.w); |
| 26 | } |
| 27 | }; |
| 28 | |
| 29 | template<length_t L, typename T, qualifier Q> |
| 30 | struct compute_srgbToRgb |
| 31 | { |
| 32 | GLM_FUNC_QUALIFIER static vec<L, T, Q> call(vec<L, T, Q> const& ColorSRGB, T Gamma) |
| 33 | { |
| 34 | return mix( |
| 35 | pow((ColorSRGB + static_cast<T>(0.055)) * static_cast<T>(0.94786729857819905213270142180095), vec<L, T, Q>(Gamma)), |
| 36 | ColorSRGB * static_cast<T>(0.07739938080495356037151702786378), |
| 37 | lessThanEqual(ColorSRGB, vec<L, T, Q>(static_cast<T>(0.04045)))); |
| 38 | } |
| 39 | }; |
| 40 | |
| 41 | template<typename T, qualifier Q> |
| 42 | struct compute_srgbToRgb<4, T, Q> |
| 43 | { |
| 44 | GLM_FUNC_QUALIFIER static vec<4, T, Q> call(vec<4, T, Q> const& ColorSRGB, T Gamma) |
| 45 | { |
| 46 | return vec<4, T, Q>(compute_srgbToRgb<3, T, Q>::call(vec<3, T, Q>(ColorSRGB), Gamma), ColorSRGB.w); |
| 47 | } |
| 48 | }; |
| 49 | }//namespace detail |
| 50 | |
| 51 | template<length_t L, typename T, qualifier Q> |
| 52 | GLM_FUNC_QUALIFIER vec<L, T, Q> convertLinearToSRGB(vec<L, T, Q> const& ColorLinear) |
| 53 | { |
| 54 | return detail::compute_rgbToSrgb<L, T, Q>::call(ColorLinear, static_cast<T>(0.41666)); |
| 55 | } |
| 56 | |
| 57 | // Based on Ian Taylor http://chilliant.blogspot.fr/2012/08/srgb-approximations-for-hlsl.html |
| 58 | template<> |
| 59 | GLM_FUNC_QUALIFIER vec<3, float, lowp> convertLinearToSRGB(vec<3, float, lowp> const& ColorLinear) |
| 60 | { |
| 61 | vec<3, float, lowp> S1 = sqrt(ColorLinear); |
| 62 | vec<3, float, lowp> S2 = sqrt(S1); |
| 63 | vec<3, float, lowp> S3 = sqrt(S2); |
| 64 | return 0.662002687f * S1 + 0.684122060f * S2 - 0.323583601f * S3 - 0.0225411470f * ColorLinear; |
| 65 | } |
| 66 | |
| 67 | template<length_t L, typename T, qualifier Q> |
| 68 | GLM_FUNC_QUALIFIER vec<L, T, Q> convertLinearToSRGB(vec<L, T, Q> const& ColorLinear, T Gamma) |
| 69 | { |
| 70 | return detail::compute_rgbToSrgb<L, T, Q>::call(ColorLinear, static_cast<T>(1) / Gamma); |
| 71 | } |
| 72 | |
| 73 | template<length_t L, typename T, qualifier Q> |
| 74 | GLM_FUNC_QUALIFIER vec<L, T, Q> convertSRGBToLinear(vec<L, T, Q> const& ColorSRGB) |
| 75 | { |
| 76 | return detail::compute_srgbToRgb<L, T, Q>::call(ColorSRGB, static_cast<T>(2.4)); |
| 77 | } |
| 78 | |
| 79 | template<length_t L, typename T, qualifier Q> |
| 80 | GLM_FUNC_QUALIFIER vec<L, T, Q> convertSRGBToLinear(vec<L, T, Q> const& ColorSRGB, T Gamma) |
| 81 | { |
| 82 | return detail::compute_srgbToRgb<L, T, Q>::call(ColorSRGB, Gamma); |
| 83 | } |
| 84 | }//namespace glm |