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@@ -33,13 +33,13 @@ struct HSL { float h; float s; float l; };
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struct LC { float L; float C; };
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// Alternative representation of (L_cusp, C_cusp)
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-// Encoded so S = C_cusp/L_cusp and T = C_cusp/(1-L_cusp)
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+// Encoded so S = C_cusp/L_cusp and T = C_cusp/(1-L_cusp)
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// The maximum value for C in the triangle is then found as fmin(S*L, T*(1-L)), for a given L
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struct ST { float S; float T; };
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static constexpr float pi = 3.1415926535897932384626433832795028841971693993751058209749445923078164062f;
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-float clamp(float x, float min, float max)
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+static float clamp(float x, float min, float max)
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{
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if (x < min)
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return min;
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@@ -49,22 +49,22 @@ float clamp(float x, float min, float max)
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return x;
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}
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-float sgn(float x)
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+static float sgn(float x)
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{
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return (float)(0.f < x) - (float)(x < 0.f);
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}
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-float srgb_transfer_function(float a)
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+static float srgb_transfer_function(float a)
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{
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return .0031308f >= a ? 12.92f * a : 1.055f * powf(a, .4166666666666667f) - .055f;
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}
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-float srgb_transfer_function_inv(float a)
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+static float srgb_transfer_function_inv(float a)
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{
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return .04045f < a ? powf((a + .055f) / 1.055f, 2.4f) : a / 12.92f;
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}
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-Lab linear_srgb_to_oklab(RGB c)
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+static Lab linear_srgb_to_oklab(RGB c)
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{
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float l = 0.4122214708f * c.r + 0.5363325363f * c.g + 0.0514459929f * c.b;
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float m = 0.2119034982f * c.r + 0.6806995451f * c.g + 0.1073969566f * c.b;
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@@ -81,7 +81,7 @@ Lab linear_srgb_to_oklab(RGB c)
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};
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}
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-RGB oklab_to_linear_srgb(Lab c)
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+static RGB oklab_to_linear_srgb(Lab c)
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{
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float l_ = c.L + 0.3963377774f * c.a + 0.2158037573f * c.b;
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float m_ = c.L - 0.1055613458f * c.a - 0.0638541728f * c.b;
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@@ -101,7 +101,7 @@ RGB oklab_to_linear_srgb(Lab c)
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// Finds the maximum saturation possible for a given hue that fits in sRGB
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// Saturation here is defined as S = C/L
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// a and b must be normalized so a^2 + b^2 == 1
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-float compute_max_saturation(float a, float b)
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+static float compute_max_saturation(float a, float b)
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{
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// Max saturation will be when one of r, g or b goes below zero.
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@@ -132,7 +132,7 @@ float compute_max_saturation(float a, float b)
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// Do one step Halley's method to get closer
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// this gives an error less than 10e6, except for some blue hues where the dS/dh is close to infinite
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- // this should be sufficient for most applications, otherwise do two/three steps
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+ // this should be sufficient for most applications, otherwise do two/three steps
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float k_l = +0.3963377774f * a + 0.2158037573f * b;
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float k_m = -0.1055613458f * a - 0.0638541728f * b;
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@@ -167,7 +167,7 @@ float compute_max_saturation(float a, float b)
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// finds L_cusp and C_cusp for a given hue
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// a and b must be normalized so a^2 + b^2 == 1
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-LC find_cusp(float a, float b)
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+static LC find_cusp(float a, float b)
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{
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// First, find the maximum saturation (saturation S = C/L)
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float S_cusp = compute_max_saturation(a, b);
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@@ -180,11 +180,11 @@ LC find_cusp(float a, float b)
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return { L_cusp , C_cusp };
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}
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-// Finds intersection of the line defined by
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+// Finds intersection of the line defined by
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// L = L0 * (1 - t) + t * L1;
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// C = t * C1;
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// a and b must be normalized so a^2 + b^2 == 1
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-float find_gamut_intersection(float a, float b, float L1, float C1, float L0, LC cusp)
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+static float find_gamut_intersection(float a, float b, float L1, float C1, float L0, LC cusp)
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{
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// Find the intersection for upper and lower half seprately
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float t;
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@@ -269,7 +269,7 @@ float find_gamut_intersection(float a, float b, float L1, float C1, float L0, LC
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return t;
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}
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-float find_gamut_intersection(float a, float b, float L1, float C1, float L0)
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+static float find_gamut_intersection(float a, float b, float L1, float C1, float L0)
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{
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// Find the cusp of the gamut triangle
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LC cusp = find_cusp(a, b);
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@@ -277,7 +277,7 @@ float find_gamut_intersection(float a, float b, float L1, float C1, float L0)
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return find_gamut_intersection(a, b, L1, C1, L0, cusp);
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}
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-RGB gamut_clip_preserve_chroma(RGB rgb)
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+static RGB gamut_clip_preserve_chroma(RGB rgb)
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{
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if (rgb.r < 1 && rgb.g < 1 && rgb.b < 1 && rgb.r > 0 && rgb.g > 0 && rgb.b > 0)
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return rgb;
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@@ -299,7 +299,7 @@ RGB gamut_clip_preserve_chroma(RGB rgb)
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return oklab_to_linear_srgb({ L_clipped, C_clipped * a_, C_clipped * b_ });
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}
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-RGB gamut_clip_project_to_0_5(RGB rgb)
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+static RGB gamut_clip_project_to_0_5(RGB rgb)
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{
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if (rgb.r < 1 && rgb.g < 1 && rgb.b < 1 && rgb.r > 0 && rgb.g > 0 && rgb.b > 0)
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return rgb;
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@@ -321,7 +321,7 @@ RGB gamut_clip_project_to_0_5(RGB rgb)
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return oklab_to_linear_srgb({ L_clipped, C_clipped * a_, C_clipped * b_ });
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}
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-RGB gamut_clip_project_to_L_cusp(RGB rgb)
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+static RGB gamut_clip_project_to_L_cusp(RGB rgb)
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{
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if (rgb.r < 1 && rgb.g < 1 && rgb.b < 1 && rgb.r > 0 && rgb.g > 0 && rgb.b > 0)
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return rgb;
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@@ -347,7 +347,7 @@ RGB gamut_clip_project_to_L_cusp(RGB rgb)
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return oklab_to_linear_srgb({ L_clipped, C_clipped * a_, C_clipped * b_ });
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}
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-RGB gamut_clip_adaptive_L0_0_5(RGB rgb, float alpha = 0.05f)
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+static RGB gamut_clip_adaptive_L0_0_5(RGB rgb, float alpha = 0.05f)
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{
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if (rgb.r < 1 && rgb.g < 1 && rgb.b < 1 && rgb.r > 0 && rgb.g > 0 && rgb.b > 0)
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return rgb;
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@@ -371,7 +371,7 @@ RGB gamut_clip_adaptive_L0_0_5(RGB rgb, float alpha = 0.05f)
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return oklab_to_linear_srgb({ L_clipped, C_clipped * a_, C_clipped * b_ });
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}
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-RGB gamut_clip_adaptive_L0_L_cusp(RGB rgb, float alpha = 0.05f)
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+static RGB gamut_clip_adaptive_L0_L_cusp(RGB rgb, float alpha = 0.05f)
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{
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if (rgb.r < 1 && rgb.g < 1 && rgb.b < 1 && rgb.r > 0 && rgb.g > 0 && rgb.b > 0)
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return rgb;
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@@ -400,7 +400,7 @@ RGB gamut_clip_adaptive_L0_L_cusp(RGB rgb, float alpha = 0.05f)
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return oklab_to_linear_srgb({ L_clipped, C_clipped * a_, C_clipped * b_ });
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}
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-float toe(float x)
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+static float toe(float x)
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{
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constexpr float k_1 = 0.206f;
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constexpr float k_2 = 0.03f;
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@@ -408,7 +408,7 @@ float toe(float x)
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return 0.5f * (k_3 * x - k_1 + sqrtf((k_3 * x - k_1) * (k_3 * x - k_1) + 4 * k_2 * k_3 * x));
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}
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-float toe_inv(float x)
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+static float toe_inv(float x)
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{
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constexpr float k_1 = 0.206f;
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constexpr float k_2 = 0.03f;
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@@ -416,7 +416,7 @@ float toe_inv(float x)
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return (x * x + k_1 * x) / (k_3 * (x + k_2));
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}
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-ST to_ST(LC cusp)
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+static ST to_ST(LC cusp)
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{
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float L = cusp.L;
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float C = cusp.C;
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@@ -426,7 +426,7 @@ ST to_ST(LC cusp)
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// Returns a smooth approximation of the location of the cusp
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// This polynomial was created by an optimization process
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// It has been designed so that S_mid < S_max and T_mid < T_max
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-ST get_ST_mid(float a_, float b_)
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+static ST get_ST_mid(float a_, float b_)
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{
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float S = 0.11516993f + 1.f / (
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+7.44778970f + 4.15901240f * b_
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@@ -448,13 +448,13 @@ ST get_ST_mid(float a_, float b_)
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}
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struct Cs { float C_0; float C_mid; float C_max; };
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-Cs get_Cs(float L, float a_, float b_)
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+static Cs get_Cs(float L, float a_, float b_)
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{
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LC cusp = find_cusp(a_, b_);
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float C_max = find_gamut_intersection(a_, b_, L, 1, L, cusp);
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ST ST_max = to_ST(cusp);
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-
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+
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// Scale factor to compensate for the curved part of gamut shape:
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float k = C_max / fmin((L * ST_max.S), (1 - L) * ST_max.T);
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@@ -481,7 +481,7 @@ Cs get_Cs(float L, float a_, float b_)
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return { C_0, C_mid, C_max };
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}
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-RGB okhsl_to_srgb(HSL hsl)
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+static RGB okhsl_to_srgb(HSL hsl)
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{
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float h = hsl.h;
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float s = hsl.s;
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@@ -539,7 +539,7 @@ RGB okhsl_to_srgb(HSL hsl)
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};
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}
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-HSL srgb_to_okhsl(RGB rgb)
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+static HSL srgb_to_okhsl(RGB rgb)
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{
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Lab lab = linear_srgb_to_oklab({
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srgb_transfer_function_inv(rgb.r),
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@@ -588,7 +588,7 @@ HSL srgb_to_okhsl(RGB rgb)
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}
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-RGB okhsv_to_srgb(HSV hsv)
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+static RGB okhsv_to_srgb(HSV hsv)
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{
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float h = hsv.h;
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float s = hsv.s;
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@@ -596,7 +596,7 @@ RGB okhsv_to_srgb(HSV hsv)
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float a_ = cosf(2.f * pi * h);
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float b_ = sinf(2.f * pi * h);
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-
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+
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LC cusp = find_cusp(a_, b_);
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ST ST_max = to_ST(cusp);
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float S_max = ST_max.S;
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@@ -635,7 +635,7 @@ RGB okhsv_to_srgb(HSV hsv)
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};
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}
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-HSV srgb_to_okhsv(RGB rgb)
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+static HSV srgb_to_okhsv(RGB rgb)
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{
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Lab lab = linear_srgb_to_oklab({
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srgb_transfer_function_inv(rgb.r),
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