render/cm: add ICC profile pipeline (#12711)

Adds an ICC profile pipeline, loading via config and applying via 3D LUTs.

2 files changed, 35 insertions, 13 deletions

diff --git a/src/render/shaders/glsl/CM.glsl b/src/render/shaders/glsl/CM.glsl
index 36c95a90..66d84885 100644
--- a/src/render/shaders/glsl/CM.glsl
+++ b/src/render/shaders/glsl/CM.glsl
@@ -6,6 +6,10 @@ uniform mat3 convertMatrix;
 
 #include "sdr_mod.glsl"
 
+uniform int useIcc;
+uniform highp sampler3D iccLut3D;
+uniform float iccLutSize;
+
 //enum eTransferFunction
 #define CM_TRANSFER_FUNCTION_BT1886     1
 #define CM_TRANSFER_FUNCTION_GAMMA22    2
@@ -65,6 +69,24 @@ uniform mat3 convertMatrix;
 
 #define M_E 2.718281828459045
 
+
+vec3 applyIcc3DLut(vec3 linearRgb01) {
+    vec3 x = clamp(linearRgb01, 0.0, 1.0);
+
+    // Map [0..1] to texel centers to avoid edge issues
+    float N = iccLutSize;
+    vec3 coord = (x * (N - 1.0) + 0.5) / N;
+
+    return texture(iccLut3D, coord).rgb;
+}
+
+vec3 xy2xyz(vec2 xy) {
+    if (xy.y == 0.0)
+        return vec3(0.0, 0.0, 0.0);
+
+    return vec3(xy.x / xy.y, 1.0, (1.0 - xy.x - xy.y) / xy.y);
+}
+
 // The primary source for these transfer functions is https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.1361-0-199802-W!!PDF-E.pdf
 vec3 tfInvPQ(vec3 color) {
     vec3 E = pow(clamp(color.rgb, vec3(0.0), vec3(1.0)), vec3(PQ_INV_M2));
@@ -250,7 +272,7 @@ vec4 fromLinear(vec4 color, int tf) {
     return color;
 }
 
-vec4 fromLinearNit(vec4 color, int tf, vec2 range) {
+vec4 fromLinearNit(vec4 color, int tf, vec2 range) {    
     if (tf == CM_TRANSFER_FUNCTION_EXT_LINEAR)
         color.rgb = color.rgb / SDR_MAX_LUMINANCE;
     else {
@@ -267,12 +289,18 @@ vec4 fromLinearNit(vec4 color, int tf, vec2 range) {
 vec4 doColorManagement(vec4 pixColor, int srcTF, int dstTF, mat3 dstxyz) {
     pixColor.rgb /= max(pixColor.a, 0.001);
     pixColor.rgb = toLinearRGB(pixColor.rgb, srcTF);
-    pixColor.rgb = convertMatrix * pixColor.rgb;
-    pixColor = toNit(pixColor, srcTFRange);
-    pixColor.rgb *= pixColor.a;
-    #include "do_tonemap.glsl"
-    pixColor = fromLinearNit(pixColor, dstTF, dstTFRange);
-    #include "do_sdr_mod.glsl"
+
+    if (useIcc == 1) {
+        pixColor.rgb = applyIcc3DLut(pixColor.rgb);
+        pixColor.rgb *= pixColor.a;
+    } else {
+        pixColor.rgb = convertMatrix * pixColor.rgb;
+        pixColor = toNit(pixColor, srcTFRange);
+        pixColor.rgb *= pixColor.a;
+        #include "do_tonemap.glsl"
+        pixColor = fromLinearNit(pixColor, dstTF, dstTFRange);
+        #include "do_sdr_mod.glsl"
+    }
 
     return pixColor;
 }
diff --git a/src/render/shaders/glsl/shadow.frag b/src/render/shaders/glsl/shadow.frag
index 71e96ddb..06aa605c 100644
--- a/src/render/shaders/glsl/shadow.frag
+++ b/src/render/shaders/glsl/shadow.frag
@@ -5,7 +5,6 @@ precision highp float;
 in vec4 v_color;
 in vec2 v_texcoord;
 
-uniform int skipCM;
 uniform int sourceTF; // eTransferFunction
 uniform int targetTF; // eTransferFunction
 uniform mat3 targetPrimariesXYZ;
@@ -18,8 +17,6 @@ uniform float roundingPower;
 uniform float range;
 uniform float shadowPower;
 
-#include "CM.glsl"
-
 float pixAlphaRoundedDistance(float distanceToCorner) {
      if (distanceToCorner > radius) {
         return 0.0;
@@ -92,8 +89,5 @@ void main() {
     // premultiply
     pixColor.rgb *= pixColor[3];
 
-	if (skipCM == 0)
-        pixColor = doColorManagement(pixColor, sourceTF, targetTF, targetPrimariesXYZ);
-
 	fragColor = pixColor;
 }
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