Worked on voxelization geometry shader

Author: domme

assets/shader/VoxelConeTracing/voxelizeGeom.shader

@@ -40,36 +40,110 @@ out VertexData {
     vec2 uv;
 } Out;
 
-// Constants for the projection planes to key into the worldAxes array
-const uint YZ = 0;
-const uint XZ = 1;
-const uint XY = 2;
-
 // (TODO) replace with an uniform
 // This is the lower left corner of the voxel grid
 const vec3 voxelGridOrigin = vec3(0.0, 0.0, 0.0);
 
 // (TODO) replace with an uniform
+// This is the length of the voxel grid, but not neccessarily the number of
+// voxels (only if they have a side-lenght of 1)
 const float voxelGridLength = 12;
 
+// Constants for the projection planes to key into the worldAxes array
+const uint YZ = 0;
+const uint XZ = 1;
+const uint XY = 2;
+
+// Constants to key into worldaxes
+const uint X = 0;
+const uint Y = 1;
+const uint Z = 2;
+
 const vec3 worldAxes[3] = vec3[3]( vec3(1.0, 0.0, 0.0),
                                    vec3(0.0, 1.0, 0.0),
                                    vec3(0.0, 0.0, 1.0) );
 
+mat4 viewProjs[3];
+
+void init() {
+  mat4 camProjMatrix = mat4(2.0 / voxelGridLength, 0, 0, 0,
+                                  0, 2.0 / voxelGridLength, 0, 0,
+                                  0, 0, - 2.0 / voxelGridLength, 0,
+                                  0, 0, 0, 1);
+
+  vec3 camPositions[3] =
+   vec3[3] ( voxelGridOrigin
+               + vec3(voxelGridLength,                               // Right
+                      voxelGridLength / 2.0, voxelGridLength / 2.0),
+
+             voxelGridOrigin
+                + vec3(voxelGridLength / 2.0, voxelGridLength,      // TOP
+                       voxelGridLength / 2.0),
+
+             voxelGridOrigin
+                + vec3(voxelGridLength / 2.0, voxelGridLength / 2.0,  // Far
+                       voxelGridLength) );
+
+  mat4 viewMats[3] = mat4[3]( mat4(1.0),    // Right
+                           mat4(1.0),    // Top
+                           mat4(1.0) );  // Far
+
+  // View Matrix for right camera
+  viewMats[0][0] = vec4(0.0, 0.0, 1.0, 0.0);
+  viewMats[0][1] = vec4(0.0, 1.0, 0.0, 0.0);
+  viewMats[0][2] = vec4(1.0, 0.0, 0.0, 0.0);
+  viewMats[0][3] = vec4(dot(viewMats[0][0].xyz, -camPositions[0]),
+                        dot(viewMats[0][1].xyz, -camPositions[0]),
+                        dot(viewMats[0][2].xyz, -camPositions[0]), 1.0);
+
+  // View Matrix for top camera
+  viewMats[1][0] = vec4(1.0, 0.0, 0.0, 0.0);
+  viewMats[1][1] = vec4(0.0, 0.0, 1.0, 0.0);
+  viewMats[1][2] = vec4(0.0, 1.0, 0.0, 0.0);
+  viewMats[1][3] = vec4(dot(viewMats[1][0].xyz, -camPositions[1]),
+                        dot(viewMats[1][1].xyz, -camPositions[1]),
+                        dot(viewMats[1][2].xyz, -camPositions[1]), 1.0);
+
+
+  // View Matrix for far camera
+  viewMats[2][0] = vec4(-1.0, 0.0, 0.0, 0.0);
+  viewMats[2][1] = vec4(0.0, 1.0, 0.0, 0.0);
+  viewMats[2][2] = vec4(0.0, 0.0, 1.0, 0.0);
+  viewMats[2][3] = vec4(dot(viewMats[2][0].xyz, -camPositions[2]),
+                        dot(viewMats[2][1].xyz, -camPositions[2]),
+                        dot(viewMats[2][2].xyz, -camPositions[2]), 1.0);
+
+  viewProjs = mat4[3]( mat4(1.0), mat4(1.0), mat4(1.0) );
+  viewProjs[0] = camProjMatrix * viewMats[0];
+  viewProjs[1] = camProjMatrix * viewMats[1];
+  viewProjs[2] = camProjMatrix * viewMats[2];
+}
 
-
-const mat4 camProjMatrix = mat4(2.0 / voxelGridLength, 0, 0, 0,
-                                0, 2.0 / voxelGridLength, 0, 0,
-                                0, 0, - 2.0 / voxelGridLength, 0,
-                                0, 0, 0, 1);
-
-const vec3 camPositions[3] = vec3[3] ( voxelGridOrigin + vec3(voxelGridLength, voxelGridLength / 2.0, voxelGridLength / 2.0),
-                                       voxelGridOrigin + vec3(voxelGridLength / 2.0, voxelGridLength, voxelGridLength / 2.0),
-                                       voxelGridOrigin + vec3(voxelGridLength / 2.0, voxelGridLength / 2.0, voxelGridLength) );
-                                      
-
-const mat4 camViewMatrices[3] = mat4[3](
-  mat4(
+mat4 lookAt(const in vec3 eye, const in vec3 at, const in vec3 up) {
+  /*
+  detail::tvec3<T> f = normalize(center - eye);
+    detail::tvec3<T> u = normalize(up);
+    detail::tvec3<T> s = normalize(cross(f, u));
+    u = cross(s, f);
+
+    detail::tmat4x4<T> Result(1);
+    Result[0][0] = s.x;
+    Result[1][0] = s.y;
+    Result[2][0] = s.z;
+    Result[0][1] = u.x;
+    Result[1][1] = u.y;
+    Result[2][1] = u.z;
+    Result[0][2] =-f.x;
+    Result[1][2] =-f.y;
+    Result[2][2] =-f.z;
+    Result[3][0] =-dot(s, eye);
+    Result[3][1] =-dot(u, eye);
+    Result[3][2] = dot(f, eye);
+    return Result;
+  */
+
+  return mat4(1.0);
+}
 
 
 uint calcProjAxis() {
@@ -91,7 +165,7 @@ uint calcProjAxis() {
 
 void main()
 {
-
+  init();
 
   uint projAxisIdx = calcProjAxis();
 
@@ -102,10 +176,10 @@ void main()
                  vec3(In[i].pos.xy, 0.0) ); // XY-plane
 
     // (TODO) +Z or -Z?
-    vec3 clipSpacePos = ((In[i].pos - voxelGridOrigin) / maxVoxelGridSize) * 2.0 - 1.0;
+    vec3 clipSpacePos = ((In[i].pos - voxelGridOrigin) / voxelGridLength) * 2.0 - 1.0;
     gl_Position = vec4(clipSpacePos, 1.0);
 
-    Out.posVoxelGrid = (In[i].pos - voxelGridOrigin) + (maxVoxelGridSize/2.0); // 0..maxVoxelGridSize
+    Out.posVoxelGrid = (In[i].pos - voxelGridOrigin) + (voxelGridLength/2.0); // 0..voxelGridLength
     Out.normal = In[i].normal;
     Out.uv = In[i].uv;
 

demos/VoxelConeTracing/src/VoxelConeTracing/main.cpp

@@ -96,6 +96,7 @@ void initTex3D(kore::Texture* tex, const ETex3DContent texContent) {
   texProps.pixelType = GL_UNSIGNED_BYTE;
 
 
+
   // Create data
   glm::detail::tvec4<unsigned char> colorValues[VOXEL_GRID_RESOLUTION_X]
                                                [VOXEL_GRID_RESOLUTION_Y]
@@ -183,7 +184,7 @@ void setupVoxelizeTest() {
   sceneMgr->getSceneNodesByComponent(COMPONENT_MESH, meshNodes);
 
 
-  /*
+  ///*
   ShaderProgramPass* voxelizePass = new ShaderProgramPass;
   voxelizePass->setShaderProgram(voxelizeShader);
 
@@ -245,7 +246,7 @@ void setupVoxelizeTest() {
   }
 
    backBufferStage->addProgramPass(voxelizePass);
-   */
+   //*/
 
 
   // Init 3D texture sampling procedure