improved reflections

minor code improvements and bugfixes

mesh.cpp

@@ -65,15 +65,15 @@ namespace vb01{
 		irradianceShader = new Shader(libPath + "irradiance");
 		brdfIntegrationShader = new Shader(libPath + "brdfIntegration");
 
-		prefilterMap = new Texture(reflectionSize, false);
+		prefilterMap = new Texture(preFilterMapSize, false);
-		irradianceMap = new Texture(reflectionSize, false);
+		irradianceMap = new Texture(irradianceMapSize, false);
-		postfilterMap = new Texture(reflectionSize, false, 5);
+		postfilterMap = new Texture(environmentMapSize, false, 5);
-		brdfIntegrationMap = new Texture(reflectionSize, reflectionSize, false);
+		brdfIntegrationMap = new Texture(brdfMapSize, brdfMapSize, false);
 
-		initFramebuffer(preFilterFramebuffer, preFilterRenderbuffer, reflectionSize);
+		initFramebuffer(preFilterFramebuffer, preFilterRenderbuffer, preFilterMapSize);
-		initFramebuffer(irrandianceFramebuffer, irradianceRenderbuffer, reflectionSize);
+		initFramebuffer(irrandianceFramebuffer, irradianceRenderbuffer, irradianceMapSize);
-		initFramebuffer(postFilterFramebuffer, postFilterRenderbuffer, reflectionSize);
+		initFramebuffer(postFilterFramebuffer, postFilterRenderbuffer, environmentMapSize);
-		initFramebuffer(brdfFramebuffer, brdfRenderbuffer, reflectionSize);
+		initFramebuffer(brdfFramebuffer, brdfRenderbuffer, brdfMapSize);
 
 		initMesh();
 	}
@@ -280,7 +280,8 @@ namespace vb01{
 		*/
 		glBindFramebuffer(GL_FRAMEBUFFER, preFilterFramebuffer);
 
-		glViewport(0, 0, reflectionSize, reflectionSize);
+		int width = prefilterMap->getWidth();
+		glViewport(0, 0, width, width);
 
 		Root *root = Root::getSingleton();
 		Mesh *skybox = root->getSkybox();
@@ -314,7 +315,8 @@ namespace vb01{
 		glBindFramebuffer(GL_FRAMEBUFFER, irrandianceFramebuffer);
 		glBindRenderbuffer(GL_RENDERBUFFER, irradianceRenderbuffer);
 
-		glViewport(0, 0, reflectionSize, reflectionSize);
+		int width = irradianceMapSize;
+		glViewport(0, 0, width, width);
 		irradianceShader->use();
 		irradianceShader->setMat4(proj, "proj");
 		irradianceShader->setInt(0, "environmentMap");
@@ -348,13 +350,13 @@ namespace vb01{
 		environmentShader->setMat4(proj, "proj");
 		environmentShader->setInt(0, "environmentMap");
 
-		prefilterMap->select(0);
+		prefilterMap->select();
 
 		Root *root = Root::getSingleton();
 		int numMipmaps = postfilterMap->getMipmapLevel();
 
 		for(int i = 0; i < numMipmaps; ++i){
-			u32 width = reflectionSize * pow(0.5, i);
+			u32 width = environmentMapSize * pow(0.5, i);
 			glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, width, width);
 			glViewport(0, 0, width, width);
 
@@ -382,11 +384,11 @@ namespace vb01{
 	void Mesh::updateBrdfLut(){
 		glBindFramebuffer(GL_FRAMEBUFFER, brdfFramebuffer);
 
+		int width = brdfMapSize;
+		glViewport(0, 0, width, width);
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
-		glViewport(0, 0, reflectionSize, reflectionSize);
 
 		glBindRenderbuffer(GL_RENDERBUFFER, brdfRenderbuffer);
-		glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, reflectionSize, reflectionSize);
 		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, *brdfIntegrationMap->getTexture(), 0);
 
 		brdfIntegrationShader->use();
@@ -414,12 +416,12 @@ namespace vb01{
 		int irradianceId = 10, brdfId = 11, postFilterId = 12;
 
 		shader->setInt(irradianceId, "irradianceMap");
-		shader->setInt(postFilterId, "postFilterMap");
 		shader->setInt(brdfId, "brdfIntegrationMap");
+		shader->setInt(postFilterId, "postFilterMap");
 
 		irradianceMap->select(irradianceId);
-		postfilterMap->select(postFilterId);
 		brdfIntegrationMap->select(brdfId);
+		postfilterMap->select(postFilterId);
 	}
 
 	void Mesh::render(){

mesh.h

@@ -73,7 +73,7 @@ namespace vb01{
 			void updateShapeKeys(Shader*);
 			inline glm::vec3 getUpVec(glm::vec3 dir){return (fabs(dir.y) == 1 ? glm::vec3(0, 0, -1) : glm::vec3(0, 1, 0));}
 
-			int reflectionSize = 512;
+			int irradianceMapSize = 32, preFilterMapSize = 512, environmentMapSize = 128, brdfMapSize = 512; 
 			Texture *prefilterMap = nullptr, *irradianceMap = nullptr, *postfilterMap = nullptr, *brdfIntegrationMap = nullptr;
 			Shader *environmentShader = nullptr, *irradianceShader = nullptr, *brdfIntegrationShader = nullptr;
 			u32 preFilterFramebuffer, preFilterRenderbuffer, irrandianceFramebuffer, irradianceRenderbuffer, postFilterFramebuffer, postFilterRenderbuffer, brdfFramebuffer, brdfRenderbuffer;

pbr.frag

@@ -37,7 +37,7 @@ uniform sampler2D brdfIntegrationMap;
 uniform bool albedoMapEnabled;
 uniform bool normalMapEnabled;
 uniform bool roughnessMapEnabled;
-uniform bool metallnessMapEnabled;
+uniform bool metalnessMapEnabled;
 uniform bool ambientOcclutionMapEnabled;
 uniform bool environmentMapEnabled;
 uniform vec4 albedoColor;
@@ -96,7 +96,7 @@ void main() {
 
 	float metalness = metalnessVal;
 
-	if(metallnessMapEnabled)
+	if(metalnessMapEnabled)
 		metalness = texture(textures[3].pastTexture, texCoords).r;
 
 	vec3 f0 = mix(vec3(.04), albedo.rgb, metalness);
@@ -121,7 +121,7 @@ void main() {
 		vec3 halfVec = normalize(lightDir + normal);
 
 		float D = trowbridgeReitz(normal, halfVec, roughness * roughness);
-		float k = pow(roughness * roughness + 1, 2) / 8.0;
+		float k = pow(roughness + 1, 2) / 8.0;
 		float G = geoSmith(normal, viewDir, lightDir, k);
 		vec3 F = fresnelSchlick(viewDir, halfVec, f0);
 		float nDotV = max(dot(viewDir, normal), 0);
@@ -134,21 +134,25 @@ void main() {
 		totalLightColor += (kDiff * fDiff + cookTor) * lights[i].color * attenuation * nDotL;
 	}
 
-	vec3 specular = vec3(.03);
+	vec3 specular = vec3(.03), F = vec3(0);
 
 	if(environmentMapEnabled){
     // sample both the pre-filter map and the BRDF lut and combine them together as per the Split-Sum approximation to get the IBL specular part.
-		vec3 reflVec = reflect(-viewDir, normal);
+		vec3 reflVec = reflect(-viewDir, normalize(fragPos + normal));
     const float MAX_REFLECTION_LOD = 4.0;
     vec3 prefilteredColor = textureLod(postFilterMap, reflVec, roughness * MAX_REFLECTION_LOD).rgb;    
     vec2 brdf  = texture(brdfIntegrationMap, vec2(max(dot(normal, viewDir), 0.0), roughness)).rg;
-		vec3 F = fresnelSchlickRoughness(normal, viewDir, f0, roughness);
+		F = fresnelSchlickRoughness(normal, viewDir, f0, roughness);
+    specular = prefilteredColor;
     specular = prefilteredColor * (F * brdf.x + brdf.y);
 	}
 
 	float ao = ambientOcclusion;
 
-	vec3 totalAmbientColor = (albedo.rgb + specular) * ao;
+	vec3 irradiance = texture(irradianceMap, normal).rgb;
+	vec3 diffuse = irradiance * albedo.rgb;
+	vec3 kD = (vec3(1) - F) * (1 - metalness);
+	vec3 totalAmbientColor = (kD * diffuse + specular) * ao;
 
 	vec4 finalColor = vec4(totalLightColor + totalAmbientColor, 1);
 

pbr.vert

@@ -28,10 +28,10 @@ uniform mat4 proj;
 uniform float[numShapeKeys] shapeKeyFactors; 
 
 void main(){
-	mat3 normalMat = mat3(transpose(inverse(model)));
+	mat3 normalMat = mat3(model);
-	norm = (normalMat * aNorm);
+	norm = mat3(normalMat) * aNorm;
-	tan = (normalMat * aTan);
+	tan = mat3(normalMat) * aTan;
-	biTan = (normalMat * aBiTan);
+	biTan = mat3(normalMat) * aBiTan;
 	fragPos = vec3(model * vec4(aPos, 1));
 	texCoords = aTexCoords;
 

texture.cpp

@@ -107,7 +107,7 @@ namespace vb01{
 					data = stbi_load(paths[i].c_str(), &width, &height, &numChannels, 0);
 
 					if(data){
-						glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB, width, width, 0, GL_RGB, GL_UNSIGNED_BYTE, data);	
+						glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, width, width, 0, GL_RGB, GL_UNSIGNED_BYTE, data);	
 						stbi_image_free(data);
 					}
 					else{
@@ -116,7 +116,7 @@ namespace vb01{
 					}
 				}
 				else
-					glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB, width, width, 0, GL_RGB, GL_UNSIGNED_INT, NULL);	
+					glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, width, width, 0, GL_RGB, GL_UNSIGNED_INT, NULL);	
 			}
 			else{
 				glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_DEPTH_COMPONENT, width, width, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);	
@@ -126,9 +126,14 @@ namespace vb01{
 		glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 		glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 		glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
-		glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 		glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-		glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
+
+		if(mipmapLevel > 0){
+			glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+			glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
+		}
+		else
+			glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 	}
 
 	Texture::Texture(FT_Face &face, char ch){

texture.h

@@ -22,6 +22,8 @@ namespace vb01{
 			void animate(float, KeyframeChannel);
 			inline u32* getTexture(int i = 0){return &(texture[i]);}
 			inline std::string* getPath(){return paths;}
+			inline int getWidth(){return width;}
+			inline int getHeight(){return height;}
 			inline int getNumFrames(){return numFrames;}
 			inline int getMipmapLevel(){return mipmapLevel;}
 			inline float getMixRatio(){return mixRatio;}