Avoid mode-specific transmission distance initialization (potential fix for https://github.com/o3de/o3de/pull/6428#discussion_r774259781)

Signed-off-by: Santi Paprika <santi.gonzalez.cs@gmail.com>
2021-12-23 15:33:00 +01:00
parent 2d45ecb616
commit c700b95c8d
3 changed files with 53 additions and 53 deletions
@@ -19,7 +19,8 @@ void ApplyDirectionalLights(Surface surface, inout LightingData lightingData)
    const uint shadowIndex = ViewSrg::m_shadowIndexDirectionalLight;
    float litRatio = 1.0f;
    float camToSurfDist = distance(ViewSrg::m_worldPosition, surface.position);
-    // Transmission distance inside object
+
+    // Distance travelled by the light inside the object
    float transmissionDistance = 0.0f;

    if (o_enableShadows && shadowIndex <  SceneSrg::m_directionalLightCount)
@@ -69,28 +70,25 @@ void ApplyDirectionalLights(Surface surface, inout LightingData lightingData)
        float currentLitRatio = 1.0f;

        // Transmission distance from current light inside object (default non-influential values)
-        // o_transmission_mode == NONE is not taken into account because GetBackLighting already ignores this case 
-        float currentTransmissionDistance = (o_transmission_mode == TransmissionMode::ThickObject) ? 0.0f : 9999.0f;
        if (o_enableShadows)
        {
            bool activeLight = index == shadowIndex;
+            
+            // Add contribution only if current directional light is the active one for shadows
            currentLitRatio = activeLight ? litRatio : 1.;
            if (activeLight)
            {
-                // Transmission distance (add contribution only if current directional light is the active one for shadows)
-                currentTransmissionDistance = transmissionDistance;
+                float3 backLighting = GetBackLighting(surface, lightingData, light.m_rgbIntensityLux, dirToLight, transmissionDistance);
+            
+                // Attenuation applied to hide artifacts due to low-res shadow maps (might need some work in the future)
+                float attenuation = 1.0 / pow(max(1.0, camToSurfDist/2.0), lightingData.distanceAttenuation + 1.0);
+                lightingData.translucentBackLighting += backLighting * attenuation;
            }
        }
        
        lightingData.diffuseLighting += GetDiffuseLighting(surface, lightingData, light.m_rgbIntensityLux, dirToLight) * currentLitRatio;
        lightingData.specularLighting += GetSpecularLighting(surface, lightingData, light.m_rgbIntensityLux, dirToLight) * currentLitRatio;
        
-        float3 backLighting = GetBackLighting(surface, lightingData, light.m_rgbIntensityLux, dirToLight, currentTransmissionDistance);
-        
-        // Attenuation applied to hide artifacts due to low-res shadow maps (might need some work in the future)
-        float attenuation = 1.0 / pow(max(1.0, camToSurfDist/2.0), lightingData.distanceAttenuation + 1.0);
-        
-        lightingData.translucentBackLighting += backLighting * attenuation;
    }
    
    // Add debug coloring for directional light shadow
@@ -76,28 +76,6 @@ void ApplyDiskLight(ViewSrg::DiskLight light, Surface surface, inout LightingDat

        // shadow
        float litRatio = 1.0;
-        
-        // Transmission distance from current light inside object (default non-influential values)
-        // o_transmission_mode == NONE is not taken into account because GetBackLighting already ignores this case
-        float transmissionDistance = (o_transmission_mode == TransmissionMode::ThickObject) ? 0.0f : 9999.0f;
-        if (o_enableShadows)
-        {
-            litRatio = ProjectedShadow::GetVisibility(
-                light.m_shadowIndex,
-                light.m_position,
-                surface.position,
-                -dirToConeTip,
-                surface.vertexNormal);
-             
-            if (o_transmission_mode == TransmissionMode::ThickObject)
-            {
-                transmissionDistance = ProjectedShadow::GetThickness(light.m_shadowIndex, surface.position);
-            }
-            else if (o_transmission_mode == TransmissionMode::ThinObject)
-            {
-                transmissionDistance = ProjectedShadow::GetThickness(light.m_shadowIndex, surface.position - lightingData.shrinkFactor * surface.vertexNormal);
-            }   
-        }

        if (useConeAngle && dotWithDirection < light.m_cosInnerConeAngle) // in penumbra
        {   
@@ -110,17 +88,40 @@ void ApplyDiskLight(ViewSrg::DiskLight light, Surface surface, inout LightingDat
            lightIntensity *= penumbraMask;
        }

+        if (o_enableShadows)
+        {
+            litRatio = ProjectedShadow::GetVisibility(
+                light.m_shadowIndex,
+                light.m_position,
+                surface.position,
+                -dirToConeTip,
+                surface.vertexNormal);
+             
+            // Distance travelled by the light inside the object
+            float transmissionDistance = 0.0f;
+
+            // o_transmission_mode == NONE is not taken into account because GetBackLighting already ignores this case
+            if (o_transmission_mode == TransmissionMode::ThickObject)
+            {
+                transmissionDistance = ProjectedShadow::GetThickness(light.m_shadowIndex, surface.position);
+            }
+            else if (o_transmission_mode == TransmissionMode::ThinObject)
+            {
+                transmissionDistance = ProjectedShadow::GetThickness(light.m_shadowIndex, surface.position - lightingData.shrinkFactor * surface.vertexNormal);
+            }
+
+            // Attenuation applied to hide artifacts due to low-res shadow maps (might need some work in the future)
+            float attenuation = 1.0 / pow(max(1.0, sqrt(distanceToLight2)), lightingData.distanceAttenuation + 1.0);
+        
+            // Transmission contribution
+            float3 backLighting = GetBackLighting(surface, lightingData, lightIntensity, posToLightDir, transmissionDistance);
+            
+            lightingData.translucentBackLighting += backLighting * attenuation;
+        }
+
        // Diffuse contribution
        lightingData.diffuseLighting += GetDiffuseLighting(surface, lightingData, lightIntensity, posToLightDir) * litRatio;

-        // Transmission contribution
-        float3 backLighting = GetBackLighting(surface, lightingData, lightIntensity, posToLightDir, transmissionDistance);
-        
-        // Attenuation applied to hide artifacts due to low-res shadow maps (might need some work in the future)
-        float attenuation = 1.0 / pow(max(1.0, sqrt(distanceToLight2)), lightingData.distanceAttenuation + 1.0);
-        
-        lightingData.translucentBackLighting += backLighting * attenuation;
-
        // Adjust the light direction for specular based on disk size

        // Calculate the reflection off the normal from the view direction
@@ -85,9 +85,6 @@ void ApplyPointLight(ViewSrg::PointLight light, Surface surface, inout LightingD
        // shadow
        float litRatio = 1.0;

-        // Transmission distance from current light inside object (default non-influential values)
-        // o_transmission_mode == NONE is not taken into account because GetBackLighting already ignores this case
-        float transmissionDistance = (o_transmission_mode == TransmissionMode::ThickObject) ? 0.0f : 9999.0f;
        if (o_enableShadows)
        {
            const float3 lightDir = normalize(light.m_position - surface.position);
@@ -99,6 +96,10 @@ void ApplyPointLight(ViewSrg::PointLight light, Surface surface, inout LightingD
                    lightDir,
                    surface.vertexNormal);
                        
+            // Distance travelled by the light inside the object
+            float transmissionDistance = 0.0f;
+
+            // o_transmission_mode == NONE is not taken into account because GetBackLighting already ignores this case
            if (o_transmission_mode == TransmissionMode::ThickObject)
            {
                transmissionDistance = ProjectedShadow::GetThickness(shadowIndex, surface.position);
@@ -106,20 +107,20 @@ void ApplyPointLight(ViewSrg::PointLight light, Surface surface, inout LightingD
            else if (o_transmission_mode == TransmissionMode::ThinObject)
            {
                transmissionDistance = ProjectedShadow::GetThickness(shadowIndex, surface.position - lightingData.shrinkFactor * surface.vertexNormal);
-            }                   
+            }
+            
+            // Transmission contribution
+            float3 backLighting = GetBackLighting(surface, lightingData, lightIntensity, normalize(posToLight), transmissionDistance);
+            
+            // Attenuation applied to hide artifacts due to low-res shadow maps (might need some work in the future)
+            float attenuation = 1.0 / pow(max(1.0, posToLightDist), lightingData.distanceAttenuation + 1.0);
+            
+            lightingData.translucentBackLighting += backLighting * attenuation;
        }

        // Diffuse contribution
        lightingData.diffuseLighting += GetDiffuseLighting(surface, lightingData, lightIntensity, normalize(posToLight)) * litRatio;

-        // Transmission contribution
-        float3 backLighting = GetBackLighting(surface, lightingData, lightIntensity, normalize(posToLight), transmissionDistance);
-        
-        // Attenuation applied to hide artifacts due to low-res shadow maps (might need some work in the future)
-        float attenuation = 1.0 / pow(max(1.0, posToLightDist), lightingData.distanceAttenuation + 1.0);
-        
-        lightingData.translucentBackLighting += backLighting * attenuation;
-
        // Adjust the light direcion for specular based on bulb size

        // Calculate the reflection off the normal from the view direction