IBL irradiance shader source file fix.

src/6.pbr/2.1.2.ibl_irradiance/2.1.2.background.frag

@@ -0,0 +1,16 @@
+#version 330 core
+out vec4 FragColor;
+in vec3 WorldPos;
+
+uniform samplerCube environmentMap;
+
+void main()
+{		
+    vec3 envColor = texture(environmentMap, WorldPos).rgb;
+    
+    // HDR tonemap and gamma correct
+    envColor = envColor / (envColor + vec3(1.0));
+    envColor = pow(envColor, vec3(1.0/2.2)); 
+    
+    FragColor = vec4(envColor, 1.0);
+}

src/6.pbr/2.1.2.ibl_irradiance/2.1.2.background.vs

@@ -0,0 +1,17 @@
+#version 330 core
+layout (location = 0) in vec3 pos;
+
+uniform mat4 projection;
+uniform mat4 view;
+
+out vec3 WorldPos;
+
+void main()
+{
+    WorldPos = pos;
+
+	mat4 rotView = mat4(mat3(view));
+	vec4 clipPos = projection * rotView * vec4(WorldPos, 1.0);
+
+	gl_Position = clipPos.xyww;
+}

src/6.pbr/2.1.2.ibl_irradiance/2.1.2.cubemap.vs

@@ -0,0 +1,14 @@
+#version 330 core
+layout (location = 0) in vec3 pos;
+
+out vec3 WorldPos;
+
+uniform mat4 projection;
+uniform mat4 view;
+
+void main()
+{
+    WorldPos = pos;  
+
+    gl_Position =  projection * view * vec4(WorldPos, 1.0);
+}

src/6.pbr/2.1.2.ibl_irradiance/2.1.2.equirectangular_to_cubemap.frag

@@ -0,0 +1,22 @@
+#version 330 core
+out vec4 FragColor;
+in vec3 WorldPos;
+
+uniform sampler2D equirectangularMap;
+
+const vec2 invAtan = vec2(0.1591, 0.3183);
+vec2 SampleSphericalMap(vec3 v)
+{
+    vec2 uv = vec2(atan(v.z, v.x), asin(v.y));
+    uv *= invAtan;
+    uv += 0.5;
+    return uv;
+}
+
+void main()
+{		
+    vec2 uv = SampleSphericalMap(normalize(WorldPos));
+    vec3 color = texture(equirectangularMap, uv).rgb;
+    
+    FragColor = vec4(color, 1.0);
+}

src/6.pbr/2.1.2.ibl_irradiance/ibl_irradiance.cpp

@@ -78,9 +78,9 @@ int main()
     // load and initialize shaders
     // ----------------------
     Shader pbrShader("2.1.2.pbr.vs", "2.1.2.pbr.frag");
-    Shader equirectangularToCubemapShader("2.1.1.cubemap.vs", "2.1.1.equirectangular_to_cubemap.frag");
-    Shader irradianceShader("2.1.1.cubemap.vs", "2.1.2.irradiance_convolution.frag");
-    Shader backgroundShader("2.1.1.background.vs", "2.1.1.background.frag");
+    Shader equirectangularToCubemapShader("2.1.2.cubemap.vs", "2.1.2.equirectangular_to_cubemap.frag");
+    Shader irradianceShader("2.1.2.cubemap.vs", "2.1.2.irradiance_convolution.frag");
+    Shader backgroundShader("2.1.2.background.vs", "2.1.2.background.frag");
 
     pbrShader.Use();
     glUniform1i(glGetUniformLocation(pbrShader.Program, "irradianceMap"), 0);