SSSSS comments

[subsurface_scattering] / shaders / vert_irradiance.glsl

diff --git a/shaders/vert_irradiance.glsl b/shaders/vert_irradiance.glsl
index 25770f6b2fc9ac606bbf426a5b84f0575b87da89..89ba12e63bb4cc5e62e35f7834c8f68a09d224ea 100644 (file)
--- a/shaders/vert_irradiance.glsl
+++ b/shaders/vert_irradiance.glsl
@@ -23,55 +23,37 @@ uniform mat4 lightViewInv;
 uniform mat4 projection;\r
 uniform mat4 lightProjection;\r
 \r
-vec4 blur(sampler2D tex, vec2 uv, vec2 res) {\r
-  float Pi = 6.28318530718; // Pi*2\r
-    \r
-  // GAUSSIAN BLUR SETTINGS {{{\r
-  float Directions = 16.0; // BLUR DIRECTIONS (Default 16.0 - More is better but slower)\r
-  float Quality = 4.0; // BLUR QUALITY (Default 4.0 - More is better but slower)\r
-  float Size = 8.0; // BLUR SIZE (Radius)\r
-  // GAUSSIAN BLUR SETTINGS }}}\r
-  \r
-  vec2 Radius = Size/res;\r
-  \r
-  // Pixel colour\r
-  vec4 Color = texture(tex, uv);\r
-  \r
-  // Blur calculations\r
-  for( float d=0.0; d<Pi; d+=Pi/Directions) {\r
-    for(float i=1.0/Quality; i<=1.0; i+=1.0/Quality) {\r
-      Color += texture( tex, uv+vec2(cos(d),sin(d))*Radius*i);         \r
-    }\r
-  }\r
-  \r
-  // Output to screen\r
-  Color /= Quality * Directions - 15.0;\r
-  return Color;\r
-}\r
-\r
 void main()\r
 {\r
   gl_Position = projection * view * model * vec4(pos, 1.0);\r
+  // calculate fragment position in world coordinates\r
   FragPos = vec3(model * vec4(pos, 1));\r
+  // and local coordinates\r
   LocalPos = pos;\r
+\r
   Normal = normal;\r
   \r
+  // get fragment position in the light's projection space\r
   vec4 lightSpace = lightProjection * lightView * model * vec4(pos, 1.0);\r
+  // and transform them to 2D coordinates\r
+  // (this is usually done by OpenGL after applying the vertex shader,\r
+  // so to get them here, we have to divide by w manually)\r
   lightSpace = lightSpace / lightSpace.w;\r
   vec2 shadowmapCoords = lightSpace.xy;\r
+  // map coordinates from [0 1] to [-1 +1]\r
+  // multiply by 0.99 first to shift coordinates towards the center slightly\r
+  // to prevent artifacts at the edges\r
   shadowmapCoords = vec2(\r
     (shadowmapCoords.x * 0.99 + 1) / 2,\r
     (shadowmapCoords.y * 0.99 + 1) / 2\r
   );\r
 \r
-\r
-  // blur\r
+  // sample shadowmap (brightness encodes distance of fragment to light)\r
   vec4 t = texture(shadowmapTexture, shadowmapCoords);\r
-  //vec4 t = blur(shadowmapTexture, shadowmapCoords, vec2(screenWidth, screenHeight));\r
 \r
-  BacksideIrradiance = t.r + t.g*10 + t.b*100;\r
+  BacksideIrradiance = t.r;\r
   \r
-  vec3 lightDir = (vec3(0, 0, 0) - lightPos);\r
+  // calculate backside with distance(BacksideIrradiance) and lightDir\r
+  vec3 lightDir = normalize(FragPos - lightPos);\r
   Backside = (lightPos + (lightDir * BacksideIrradiance));\r
-  //Backside = texture(shadowmapTexture, shadowmapCoords).xyz*10;\r
 }\r