Fix SRGB handling, now converting from srgb->linear properly

engine/asset/include/material_nodes.hpp

@@ -159,7 +159,7 @@ public:
     }
     
     std::string get_glsl() override {
-        std::string glsl = "vec3 final_diffuse_color = Color;\n \
+        std::string glsl = "vec3 final_diffuse_color = from_srgb_to_linear(Color);\n \
         float final_roughness = Roughness;\n \
         float final_metallic = Metallic;\n";
         

engine/renderer/src/materialcompiler.cpp

@@ -294,12 +294,13 @@ ShaderSource MaterialCompiler::compile_material_fragment(Material& material, boo
     
     if(use_ibl) {
         src += "vec3 ibl(const int probe, const ComputedSurfaceInfo surface_info, const float intensity) {\n \
+            const vec3 F = fresnel_schlick_roughness(surface_info.NdotV, surface_info.F0, surface_info.roughness);\n \
             const vec3 R = get_reflect(probe, surface_info.N);\n \
             const vec2 brdf = texture(brdfSampler, vec2(surface_info.NdotV, surface_info.roughness)).rg; \n \
             const vec3 sampledIrradiance = texture(irrandianceSampler, vec4(surface_info.N, probe)).xyz;\n \
             const vec3 prefilteredColor = textureLod(prefilterSampler, vec4(R, probe), surface_info.roughness * 4).xyz;\n \
             const vec3 diffuse = sampledIrradiance * surface_info.diffuse_color;\n \
-            const vec3 specular = prefilteredColor * (surface_info.F0 * brdf.x + 1.0 * brdf.y);\n \
+            const vec3 specular = prefilteredColor * (F * brdf.x + brdf.y);\n \
             return (diffuse + specular) * intensity;\n \
         }\n";
     }

engine/renderer/src/renderer.cpp

@@ -360,7 +360,7 @@ void Renderer::render_camera(GFXCommandBuffer* command_buffer, Scene& scene, Obj
         Vector3 front = Vector3(0.0f, 0.0f, 1.0f) * scene.get<Transform>(obj).rotation;
         
         sl.directionPower = Vector4(-front, light.power);
-        sl.colorSize = Vector4(light.color, radians(light.spot_size));
+        sl.colorSize = Vector4(utility::from_srgb_to_linear(light.color), radians(light.spot_size));
         sl.shadowsEnable = Vector4(light.enable_shadows, radians(light.size), 0, 0);
         
         sceneInfo.lights[sceneInfo.numLights++] = sl;

engine/renderer/src/scenecapture.cpp

@@ -165,7 +165,7 @@ void SceneCapture::render(GFXCommandBuffer* command_buffer, Scene* scene) {
                 Vector3 front = Vector3(0.0f, 0.0f, 1.0f) * scene->get<Transform>(obj).rotation;
                 
                 sl.directionPower = Vector4(-front, light.power);
-                sl.colorSize = Vector4(light.color, radians(light.spot_size));
+                sl.colorSize = Vector4(utility::from_srgb_to_linear(light.color), radians(light.spot_size));
                 sl.shadowsEnable = Vector4(light.enable_shadows, radians(light.size), 0, 0);
                 
                 sceneInfo.lights[sceneInfo.numLights++] = sl;
@@ -191,12 +191,6 @@ void SceneCapture::render(GFXCommandBuffer* command_buffer, Scene* scene) {
                         engine->get_renderer()->create_mesh_pipeline(*material.handle);
 
                     if(!material_indices.count(material.handle)) {
-                        // unused for now
-                        /*sceneInfo.materials[numMaterialsInBuffer].color = material->base_color;
-                        sceneInfo.materials[numMaterialsInBuffer].info[0] = material->metallic;
-                        sceneInfo.materials[numMaterialsInBuffer].info[1] = material->roughness;
-                        sceneInfo.materials[numMaterialsInBuffer].info[2] = radians(material->hue_shift);*/
-                        
                         material_indices[material.handle] = numMaterialsInBuffer++;
                     }
                 }

engine/utility/include/utility.hpp

@@ -7,6 +7,8 @@
 #include <random>
 #include <unordered_map>
 
+#include "vector.hpp"
+
 namespace utility {
     template<class Enum>
     std::string enum_to_string(const Enum e) {
@@ -95,4 +97,17 @@ namespace utility {
     inline uint16_t to_fixed(const float f) {
         return static_cast<uint16_t>(32.0f * f + 0.5f);
     }
+
+    inline Vector3 from_srgb_to_linear(const Vector3 sRGB) {
+        Vector3 linear = sRGB;
+        for(auto& component : linear.data) {
+            if(component > 0.04045f) {
+                component = std::powf((component + 0.055) / (1.055), 2.4f);
+            } else if (component <= 0.04045) {
+                component /= 12.92f;
+            }
+        }
+
+        return linear;
+    }
 }

shaders/common.nocompile.glsl

@@ -142,3 +142,19 @@ vec3 importance_sample_ggx(const vec2 Xi, const vec3 N, const float roughness) {
     
     return normalize(tangent * H.x + bitangent * H.y + N * H.z);
 }
+
+vec3 from_linear_to_srgb(const vec3 linearRGB) {
+    bvec3 cutoff = lessThan(linearRGB, vec3(0.0031308));
+    vec3 higher = vec3(1.055)*pow(linearRGB, vec3(1.0/2.4)) - vec3(0.055);
+    vec3 lower = linearRGB * vec3(12.92);
+
+    return mix(higher, lower, cutoff);
+}
+
+vec3 from_srgb_to_linear(const vec3 sRGB) {
+    bvec3 cutoff = lessThan(sRGB, vec3(0.04045));
+    vec3 higher = pow((sRGB + vec3(0.055))/vec3(1.055), vec3(2.4));
+    vec3 lower = sRGB/vec3(12.92);
+
+    return mix(higher, lower, cutoff);
+}

shaders/post.frag.glsl

@@ -11,6 +11,7 @@ layout(std430, push_constant, binding = 4) uniform PushConstant {
 };
 
 #include "smaa.glsl"
+#include "common.nocompile.glsl"
 
 layout (location = 0) in vec2 inUV;
 layout(location = 1) in vec4 inOffset;
@@ -63,5 +64,5 @@ void main() {
     
     vec3 hdrColor = sceneColor; // fading removed
     hdrColor = vec3(1.0) - exp(-hdrColor * options.z); // exposure
-    outColor = vec4(hdrColor + (sobelColor * sobel), 1.0);
+    outColor = vec4(from_linear_to_srgb(hdrColor) + (sobelColor * sobel), 1.0);
 }

shaders/sky.frag.glsl

@@ -43,6 +43,5 @@ void main() {
         0.758
     );
 
-    // apply exposure
+    out_color = vec4(color, 1.0);
-    out_color = vec4(1.0 - exp(-1.0 * color), 1.0);
 }