1 files changed, 87 insertions, 0 deletions
diff --git a/source/blender/compositor/realtime_compositor/shaders/library/gpu_shader_compositor_color_correction.glsl b/source/blender/compositor/realtime_compositor/shaders/library/gpu_shader_compositor_color_correction.glsl
new file mode 100644
index 00000000000..9b4858f03be
--- /dev/null
+++ b/source/blender/compositor/realtime_compositor/shaders/library/gpu_shader_compositor_color_correction.glsl
@@ -0,0 +1,87 @@
+#pragma BLENDER_REQUIRE(gpu_shader_common_math_utils.glsl)
+#pragma BLENDER_REQUIRE(gpu_shader_common_color_utils.glsl)
+
+void node_composite_color_correction(vec4 color,
+                                     float mask,
+                                     const vec3 enabled_channels,
+                                     float start_midtones,
+                                     float end_midtones,
+                                     float master_saturation,
+                                     float master_contrast,
+                                     float master_gamma,
+                                     float master_gain,
+                                     float master_lift,
+                                     float shadows_saturation,
+                                     float shadows_contrast,
+                                     float shadows_gamma,
+                                     float shadows_gain,
+                                     float shadows_lift,
+                                     float midtones_saturation,
+                                     float midtones_contrast,
+                                     float midtones_gamma,
+                                     float midtones_gain,
+                                     float midtones_lift,
+                                     float highlights_saturation,
+                                     float highlights_contrast,
+                                     float highlights_gamma,
+                                     float highlights_gain,
+                                     float highlights_lift,
+                                     const vec3 luminance_coefficients,
+                                     out vec4 result)
+{
+  const float margin = 0.10;
+  const float margin_divider = 0.5 / margin;
+  float level = (color.r + color.g + color.b) / 3.0;
+  float level_shadows = 0.0;
+  float level_midtones = 0.0;
+  float level_highlights = 0.0;
+  if (level < (start_midtones - margin)) {
+    level_shadows = 1.0;
+  }
+  else if (level < (start_midtones + margin)) {
+    level_midtones = ((level - start_midtones) * margin_divider) + 0.5;
+    level_shadows = 1.0 - level_midtones;
+  }
+  else if (level < (end_midtones - margin)) {
+    level_midtones = 1.0;
+  }
+  else if (level < (end_midtones + margin)) {
+    level_highlights = ((level - end_midtones) * margin_divider) + 0.5;
+    level_midtones = 1.0 - level_highlights;
+  }
+  else {
+    level_highlights = 1.0;
+  }
+
+  float contrast = level_shadows * shadows_contrast;
+  contrast += level_midtones * midtones_contrast;
+  contrast += level_highlights * highlights_contrast;
+  contrast *= master_contrast;
+  float saturation = level_shadows * shadows_saturation;
+  saturation += level_midtones * midtones_saturation;
+  saturation += level_highlights * highlights_saturation;
+  saturation *= master_saturation;
+  float gamma = level_shadows * shadows_gamma;
+  gamma += level_midtones * midtones_gamma;
+  gamma += level_highlights * highlights_gamma;
+  gamma *= master_gamma;
+  float gain = level_shadows * shadows_gain;
+  gain += level_midtones * midtones_gain;
+  gain += level_highlights * highlights_gain;
+  gain *= master_gain;
+  float lift = level_shadows * shadows_lift;
+  lift += level_midtones * midtones_lift;
+  lift += level_highlights * highlights_lift;
+  lift += master_lift;
+
+  float inverse_gamma = 1.0 / gamma;
+  float luma = get_luminance(color.rgb, luminance_coefficients);
+
+  vec3 corrected = luma + saturation * (color.rgb - luma);
+  corrected = 0.5 + (corrected - 0.5) * contrast;
+  corrected = fallback_pow(corrected * gain + lift, inverse_gamma, corrected);
+  corrected = mix(color.rgb, corrected, min(mask, 1.0));
+
+  result.rgb = mix(corrected, color.rgb, equal(enabled_channels, vec3(0.0)));
+  result.a = color.a;
+}