Address comments

demo/shaders/generated_msl/bloom_combine.frag.metal

@@ -61,7 +61,7 @@ static inline __attribute__((always_inline))
 float3 visualize_value(thread const float& val)
 {
     float g = 1.0 - ((0.20000000298023223876953125 * (val - 3.2360498905181884765625)) * (val - 3.2360498905181884765625));
-    float b = 1.0 - ((1.0 * (val - 1.0)) * (val - 1.0));
+    float b = val;
     float r = 1.0 - (1.0 / ((0.5 * val) - 0.5));
     if (val > 1.0)
     {
@@ -80,55 +80,54 @@ float luma(thread const float3& color)
     return dot(color, float3(0.2989999949932098388671875, 0.58700001239776611328125, 0.114000000059604644775390625));
 }
 
-fragment main0_out main0(main0_in in [[stage_in]], constant spvDescriptorSetBuffer0& spvDescriptorSet0 [[buffer(0)]])
+static inline __attribute__((always_inline))
+float3 tonemap(thread const float3& color, thread const int& tonemapper_type)
 {
-    constexpr sampler smp(mip_filter::linear, compare_func::never, max_anisotropy(1));
-    main0_out out = {};
-    float4 color = spvDescriptorSet0.in_color.sample(smp, in.inUV) + spvDescriptorSet0.in_blur.sample(smp, in.inUV);
-    if ((*spvDescriptorSet0.config).tonemapper_type == 1)
+    switch (tonemapper_type)
     {
-        float3 param = color.xyz;
-        float3 _227 = tonemap_aces_fitted(param);
-        out.out_sdr = float4(_227, color.w);
-    }
-    else
-    {
-        if ((*spvDescriptorSet0.config).tonemapper_type == 2)
+        case 1:
+        {
+            float3 param = color;
+            float3 _196 = tonemap_aces_fitted(param);
+            return _196;
+        }
+        case 2:
+        {
+            float3 param_1 = color;
+            return tonemap_aces_film_simple(param_1);
+        }
+        case 3:
         {
-            float3 param_1 = color.xyz;
-            out.out_sdr = float4(tonemap_aces_film_simple(param_1), color.w);
+            return color / (color + float3(1.0));
         }
-        else
+        case 4:
         {
-            if ((*spvDescriptorSet0.config).tonemapper_type == 3)
-            {
-                out.out_sdr = float4(color.xyz / (color.xyz + float3(1.0)), color.w);
-            }
-            else
-            {
-                if ((*spvDescriptorSet0.config).tonemapper_type == 4)
-                {
-                    float max_val = fast::max(color.x, fast::max(color.y, color.z));
-                    float param_2 = max_val;
-                    out.out_sdr = float4(visualize_value(param_2), color.w);
-                }
-                else
-                {
-                    if ((*spvDescriptorSet0.config).tonemapper_type == 5)
-                    {
-                        float3 param_3 = color.xyz;
-                        float l = luma(param_3);
-                        float param_4 = l;
-                        out.out_sdr = float4(visualize_value(param_4), color.w);
-                    }
-                    else
-                    {
-                        out.out_sdr = color;
-                    }
-                }
-            }
+            float max_val = fast::max(color.x, fast::max(color.y, color.z));
+            float param_2 = max_val;
+            return visualize_value(param_2);
+        }
+        case 5:
+        {
+            float3 param_3 = color;
+            float l = luma(param_3);
+            float param_4 = l;
+            return visualize_value(param_4);
+        }
+        default:
+        {
+            return color;
         }
     }
+}
+
+fragment main0_out main0(main0_in in [[stage_in]], constant spvDescriptorSetBuffer0& spvDescriptorSet0 [[buffer(0)]])
+{
+    constexpr sampler smp(mip_filter::linear, compare_func::never, max_anisotropy(1));
+    main0_out out = {};
+    float4 color = spvDescriptorSet0.in_color.sample(smp, in.inUV) + spvDescriptorSet0.in_blur.sample(smp, in.inUV);
+    float3 param = color.xyz;
+    int param_1 = (*spvDescriptorSet0.config).tonemapper_type;
+    out.out_sdr = float4(tonemap(param, param_1), color.w);
     return out;
 }
 

demo/shaders/glsl/bloom_combine.frag

@@ -1,5 +1,6 @@
 #version 450
 #extension GL_ARB_separate_shader_objects : enable
+#include "tonemapping.glsl"
 
 // @[export]
 layout (set = 0, binding = 0) uniform texture2D in_color;
@@ -29,99 +30,10 @@ layout (location = 0) in vec2 inUV;
 
 layout (location = 0) out vec4 out_sdr;
 
-// The code for ACESFitted was originally written by Stephen Hill (@self_shadow), who deserves all
-// credit for coming up with this fit and implementing it. Buy him a beer next time you see him. :)
-// The code is licensed under the MIT license
-
-// sRGB => XYZ => D65_2_D60 => AP1 => RRT_SAT
-const mat3 ACESInputMat =
-{
-    {0.59719, 0.35458, 0.04823},
-    {0.07600, 0.90834, 0.01566},
-    {0.02840, 0.13383, 0.83777}
-};
-
-// ODT_SAT => XYZ => D60_2_D65 => sRGB
-const mat3 ACESOutputMat =
-{
-    { 1.60475, -0.53108, -0.07367},
-    {-0.10208,  1.10813, -0.00605},
-    {-0.00327, -0.07276,  1.07602}
-};
-
-vec3 RRT_and_ODT_fit(vec3 v)
-{
-    vec3 a = v * (v + 0.0245786f) - 0.000090537f;
-    vec3 b = v * (0.983729f * v + 0.4329510f) + 0.238081f;
-    return a / b;
-}
-
-vec3 tonemap_aces_fitted(vec3 color)
-{
-    color = ACESInputMat * color;
-
-    // Apply RRT and ODT
-    color = RRT_and_ODT_fit(color);
-
-    color = ACESOutputMat * color;
-
-    // Clamp to [0, 1]
-    color = clamp(color, 0, 1);
-
-    return color;
-}
-
-// source: https://knarkowicz.wordpress.com/2016/01/06/aces-filmic-tone-mapping-curve/
-vec3 tonemap_aces_film_simple(vec3 x)
-{
-    float a = 2.51f;
-    float b = 0.03f;
-    float c = 2.43f;
-    float d = 0.59f;
-    float e = 0.14f;
-    return clamp((x*(a*x+b))/(x*(c*x+d)+e), 0.0, 1.0);
-}
-
-float luma(vec3 color) {
-  return dot(color, vec3(0.299, 0.587, 0.114));
-}
-
-vec3 visualize_value(float val) {
-    // parabolic curves visualize the range
-    // blue is used to visualize 0-1 exclusively
-    // green covers 0-5
-    // red is 3+
-    float g = 1 - 0.2 * (val - 3.23605) * (val - 3.23605);
-    float b = 1 - 1 * (val - 1) * (val - 1);
-    float r = 1 - 1 / (0.5 * val - 0.5);
-    if (val > 1.0) { 
-        b = 0;
-    }
-    if (val < 3.0) {
-        r = 0;
-    }
-    return clamp(vec3(r, g, b), 0, 1);
-}
 
 void main()
 {
     vec4 color = texture(sampler2D(in_color, smp), inUV) + texture(sampler2D(in_blur, smp), inUV);
 
-    // tonemapping.. TODO: implement auto-exposure
-    if (config.tonemapper_type == 1) {
-        out_sdr = vec4(tonemap_aces_fitted(color.rgb), color.a);
-    } else if (config.tonemapper_type == 2) {
-        out_sdr = vec4(tonemap_aces_film_simple(color.rgb), color.a);
-    } else if (config.tonemapper_type == 3) {
-        out_sdr = vec4(color.rgb / (color.rgb + vec3(1.0)), color.a);
-    } else if (config.tonemapper_type == 4) {
-        float max_val = max(color.r, max(color.g, color.b));
-        out_sdr = vec4(visualize_value(max_val), color.a);
-    } else if (config.tonemapper_type == 5) {
-        float l = luma(color.rgb);
-        out_sdr = vec4(visualize_value(l), color.a);
-    } else {
-        out_sdr = color;
-    }
-    // out_sdr = vec4(mapped, color.a);
+    out_sdr = vec4(tonemap(color.rgb, config.tonemapper_type), color.a);
 }

demo/shaders/glsl/tonemapping.glsl

@@ -0,0 +1,107 @@
+// The code for ACESFitted was originally written by Stephen Hill (@self_shadow), who deserves all
+// credit for coming up with this fit and implementing it. Buy him a beer next time you see him. :)
+// The code is licensed under the MIT license. The code has been converted to glsl, and was originally found at:
+// https://github.com/TheRealMJP/BakingLab/blob/master/BakingLab/ACES.hlsl
+
+// sRGB => XYZ => D65_2_D60 => AP1 => RRT_SAT
+const mat3 ACESInputMat =
+{
+    {0.59719, 0.35458, 0.04823},
+    {0.07600, 0.90834, 0.01566},
+    {0.02840, 0.13383, 0.83777}
+};
+
+// ODT_SAT => XYZ => D60_2_D65 => sRGB
+const mat3 ACESOutputMat =
+{
+    { 1.60475, -0.53108, -0.07367},
+    {-0.10208,  1.10813, -0.00605},
+    {-0.00327, -0.07276,  1.07602}
+};
+
+vec3 RRT_and_ODT_fit(vec3 v)
+{
+    vec3 a = v * (v + 0.0245786f) - 0.000090537f;
+    vec3 b = v * (0.983729f * v + 0.4329510f) + 0.238081f;
+    return a / b;
+}
+
+vec3 tonemap_aces_fitted(vec3 color)
+{
+    color = ACESInputMat * color;
+
+    // Apply RRT and ODT
+    color = RRT_and_ODT_fit(color);
+
+    color = ACESOutputMat * color;
+
+    // Clamp to [0, 1]
+    color = clamp(color, 0, 1);
+
+    return color;
+}
+
+// source: https://knarkowicz.wordpress.com/2016/01/06/aces-filmic-tone-mapping-curve/
+vec3 tonemap_aces_film_simple(vec3 x)
+{
+    float a = 2.51f;
+    float b = 0.03f;
+    float c = 2.43f;
+    float d = 0.59f;
+    float e = 0.14f;
+    return clamp((x*(a*x+b))/(x*(c*x+d)+e), 0.0, 1.0);
+}
+
+float luma(vec3 color) {
+  return dot(color, vec3(0.299, 0.587, 0.114));
+}
+
+vec3 visualize_value(float val) {
+    // blue is used to visualize 0-1 exclusively in a linear fashion.
+    // green covers 0-5 and is a parabolic curve, so it transitions over into red.
+    // red is 3+ and is a log-ish curve so that it can handle differences in very large values
+    float g = 1 - 0.2 * (val - 3.23605) * (val - 3.23605);
+    float b = val;
+    float r = 1 - 1 / (0.5 * val - 0.5);
+    // the transition blue -> green is hard, to make it easier to spot when values go over 1
+    if (val > 1.0) { 
+        b = 0;
+    }
+    if (val < 3.0) {
+        r = 0;
+    }
+    return clamp(vec3(r, g, b), 0, 1);
+}
+
+// Should be kept in sync with the constants in TonemapperType
+const int TM_StephenHillACES = 1;
+const int TM_SimplifiedLumaACES = 2;
+const int TM_LogDerivative = 3;
+const int TM_VisualizeRGBMax = 4;
+const int TM_VisualizeLuma = 5;
+
+vec3 tonemap(vec3 color, int tonemapper_type) {
+    // tonemapping.. TODO: implement auto-exposure
+    switch (tonemapper_type) {
+        case TM_StephenHillACES:  {
+            return tonemap_aces_fitted(color.rgb);
+        } break;
+        case TM_SimplifiedLumaACES: {
+            return tonemap_aces_film_simple(color.rgb);
+        } break;
+        case TM_LogDerivative: {
+            return color.rgb / (color.rgb + vec3(1.0));
+        } break;
+        case TM_VisualizeRGBMax: {
+            float max_val = max(color.r, max(color.g, color.b));
+            return visualize_value(max_val);
+        } break;
+        case TM_VisualizeLuma: {
+            float l = luma(color.rgb);
+            return visualize_value(l);
+        } break;
+        default: {
+            return color;
+        } break;
+    }
+}