feat: simplify DirectLight to radiance and direction. Use dotNL inste…

…ad of normalFluxRatio.
bhouston · Jul 28, 2020 · e623d6a · e623d6a
1 parent 2dc16f7
commit e623d6a
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Showing 16 changed files with 66 additions and 106 deletions.
diff --git a/src/examples/brdfs/clearcoat/fragment.glsl b/src/examples/brdfs/clearcoat/fragment.glsl
@@ -12,7 +12,6 @@ uniform sampler2D albedoMap;
 
 uniform sampler2D clearCoatBumpMap;
 
-
 #pragma include <brdfs/common>
 #pragma include <lighting/punctual>
 #pragma include <brdfs/ambient/basic>
@@ -47,18 +46,15 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float clearCoatNormalFluxRatio = saturate( dot( lightDirection, clearCoatSurface.normal ) );
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float clearCoatDotNL = saturate( dot( directLight.direction, clearCoatSurface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * clearCoatNormalFluxRatio *
-    BRDF_Specular_GGX( clearCoatSurface, lightDirection, clearCoatF0, clearCoatRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * clearCoatDotNL *
+    BRDF_Specular_GGX( clearCoatSurface, directLight.direction, clearCoatF0, clearCoatRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/brdfs/lambert/fragment.glsl b/src/examples/brdfs/lambert/fragment.glsl
@@ -36,13 +36,10 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/brdfs/sheen/fragment.glsl b/src/examples/brdfs/sheen/fragment.glsl
@@ -42,17 +42,14 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Sheen_Charlie( surface, lightDirection, sheenColor, sheenIntensity, sheenRoughness ) ;
-  outgoingRadiance +=  (1. - sheenIntensity ) * lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Sheen_Charlie( surface, directLight.direction, sheenColor, sheenIntensity, sheenRoughness ) ;
+  outgoingRadiance +=  (1. - sheenIntensity ) * directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/brdfs/specular/fragment.glsl b/src/examples/brdfs/specular/fragment.glsl
@@ -41,15 +41,12 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/brdfs/specularAnisotropic/fragment.glsl b/src/examples/brdfs/specularAnisotropic/fragment.glsl
@@ -44,15 +44,12 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/lights/directional/fragment.glsl b/src/examples/lights/directional/fragment.glsl
@@ -38,15 +38,12 @@ void main() {
   DirectLight directLight;
   directionalLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/lights/multi/fragment.glsl b/src/examples/lights/multi/fragment.glsl
@@ -64,14 +64,11 @@ void main() {
       directionalLightToDirectLight( surface, punctualLight, directLight );
     }
 
-    vec3 lightDirection = directLight.lightDirection;
-    vec3 lightRadiance = directLight.radiance;
+    float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
-    float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
-
-    outgoingRadiance += lightRadiance * normalFluxRatio *
-      BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-    outgoingRadiance += lightRadiance * normalFluxRatio *
+    outgoingRadiance += directLight.radiance * dotNL *
+      BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+    outgoingRadiance += directLight.radiance * dotNL *
       BRDF_Diffuse_Lambert( albedo );
 
   }

diff --git a/src/examples/lights/point/fragment.glsl b/src/examples/lights/point/fragment.glsl
@@ -44,15 +44,12 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/lights/spot/fragment.glsl b/src/examples/lights/spot/fragment.glsl
@@ -46,15 +46,12 @@ void main() {
   DirectLight directLight;
   spotLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/materials/outputChannels/fragment.glsl b/src/examples/materials/outputChannels/fragment.glsl
@@ -54,16 +54,17 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 irradiance = directLight.irradiance;
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outputDiffuse;
   vec3 outputSpecular;
-  vec3 outputColor;
-  outputColor += outputChannels.specular = irradiance * BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness );
-  outputColor += outputChannels.diffuse = irradiance * BRDF_Diffuse_Lambert( albedo );
+  vec3 outputRadiance;
+  outputRadiance += outputChannels.specular = directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness );
+  outputRadiance += outputChannels.diffuse = directLight.radiance * dotNL *
+    BRDF_Diffuse_Lambert( albedo );
 
-  outputChannels.beauty = linearTosRGB( outputColor );
+  outputChannels.beauty = linearTosRGB( outputRadiance );
 
   int newFragmentOutputs = int( mod(( -gl_FragCoord.x * 3. + gl_FragCoord.y ) * 0.002 + float( time ) / 3000., 13. ) );
 

diff --git a/src/examples/microgeometry/bump/fragment.glsl b/src/examples/microgeometry/bump/fragment.glsl
@@ -42,15 +42,12 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/microgeometry/displacement/fragment.glsl b/src/examples/microgeometry/displacement/fragment.glsl
@@ -44,15 +44,12 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/microgeometry/normals/fragment.glsl b/src/examples/microgeometry/normals/fragment.glsl
@@ -44,15 +44,12 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/examples/microgeometry/normals2/fragment.glsl b/src/examples/microgeometry/normals2/fragment.glsl
@@ -44,15 +44,12 @@ void main() {
   DirectLight directLight;
   pointLightToDirectLight( surface, punctualLight, directLight );
 
-  vec3 lightDirection = directLight.lightDirection;
-  vec3 lightRadiance = directLight.radiance;
-
-  float normalFluxRatio = saturate( dot( lightDirection, surface.normal ) );
+  float dotNL = saturate( dot( directLight.direction, surface.normal ) );
 
   vec3 outgoingRadiance;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
-    BRDF_Specular_GGX( surface, lightDirection, specularF0, specularRoughness ) ;
-  outgoingRadiance += lightRadiance * normalFluxRatio *
+  outgoingRadiance += directLight.radiance * dotNL *
+    BRDF_Specular_GGX( surface, directLight.direction, specularF0, specularRoughness ) ;
+  outgoingRadiance += directLight.radiance * dotNL *
     BRDF_Diffuse_Lambert( albedo );
 
   gl_FragColor.rgb = linearTosRGB( outgoingRadiance );

diff --git a/src/lib/shaders/includes/brdfs/common.glsl b/src/lib/shaders/includes/brdfs/common.glsl
@@ -1,9 +1,8 @@
 #pragma once
 
-// Q: should this be radiance?  Then we can change its interaction based on the different surface normals?
 struct DirectLight {
 	vec3 radiance;        // in standard BRDF notation: L[i](w[i])
-	vec3 lightDirection;  // in standard BRDF notation: w[i]
+	vec3 direction;  // in standard BRDF notation: w[i]
 };
 
 struct Surface {

diff --git a/src/lib/shaders/includes/lighting/punctual.glsl b/src/lib/shaders/includes/lighting/punctual.glsl
@@ -55,7 +55,7 @@ void pointLightToDirectLight( in Surface surface, in PunctualLight punctualLight
   float lightAttenuation = getRangeAttenuation( length( surfaceToLight ), punctualLight.range );
   vec3 lightDirection = normalize( surfaceToLight );
 
-  directLight.lightDirection = lightDirection;
+  directLight.direction = lightDirection;
   directLight.radiance = punctualLight.intensity * lightAttenuation;
 }
 
@@ -66,12 +66,12 @@ void spotLightToDirectLight( in Surface surface, in PunctualLight punctualLight,
   float lightAttenuation = getRangeAttenuation( length( surfaceToLight ), punctualLight.range );
   lightAttenuation *= getSpotAttenuation( lightDirection, punctualLight );
 
-  directLight.lightDirection = lightDirection;
+  directLight.direction = lightDirection;
   directLight.radiance = punctualLight.intensity * lightAttenuation;
 }
 
 void directionalLightToDirectLight( in Surface surface, in PunctualLight punctualLight, out DirectLight directLight ) {
 
-  directLight.lightDirection = -punctualLight.direction;
+  directLight.direction = -punctualLight.direction;
 	directLight.radiance = punctualLight.intensity;
 }