normal maps

include/client/model.hpp

@@ -31,6 +31,8 @@ struct Vertex {
     glm::vec2 textureCoords;
     int m_boneIDs[MAX_BONE_INFLUENCE]; /* Bone indices which influence the vertex */
     float m_weights[MAX_BONE_INFLUENCE]; /* Weights for each bone */
+    glm::vec3 tangent;
+    glm::vec3 bitangent;
 };
 
 class Texture {
@@ -115,6 +117,7 @@ class Mesh : public Renderable {
 
     //  render data opengl needs
     GLuint VAO, VBO, EBO;
+    void setupNormalMaps();
 };
 
 

src/client/client.cpp

@@ -202,13 +202,13 @@ bool Client::init() {
     auto deferred_light_box_frag_path = shaders_dir / "deferred_light_box.frag";
     this->deferred_light_box_shader = std::make_shared<Shader>(deferred_light_box_vert_path.string(), deferred_light_box_frag_path.string());
 
-    auto floor_model_path = env_models_dir / "floor.obj";
+    auto floor_model_path = env_models_dir / "floor-normal.obj";
     this->floor_model = std::make_unique<Model>(floor_model_path.string(), true);
 
-    auto wall_model_path = env_models_dir / "wall.obj";
+    auto wall_model_path = env_models_dir / "wall-normals.obj";
     this->wall_model = std::make_unique<Model>(wall_model_path.string(), true);
 
-    auto pillar_model_path = env_models_dir / "pillar.obj";
+    auto pillar_model_path = env_models_dir / "pillar-normals.obj";
     this->pillar_model = std::make_unique<Model>(pillar_model_path.string(), true);
 
     auto torchlight_model_path = env_models_dir / "exit.obj";

src/client/model.cpp

@@ -14,9 +14,11 @@
 #include <iostream>
 #include <filesystem>
 
+#include "assimp/postprocess.h"
 #include "client/renderable.hpp"
 #include "client/constants.hpp"
 #include "client/util.hpp"
+#include "glm/ext/quaternion_geometric.hpp"
 #include "server/game/torchlight.hpp"
 #include "shared/game/sharedobject.hpp"
 #include "shared/utilities/constants.hpp"
@@ -44,11 +46,14 @@ Mesh::Mesh(
     const Material& material) : 
     vertices(vertices), indices(indices), textures(textures), material(material) {
 
+    setupNormalMaps();
+
     glGenVertexArrays(1, &VAO);
     glGenBuffers(1, &VBO);
     glGenBuffers(1, &EBO);
 
     glBindVertexArray(VAO);
+
     glBindBuffer(GL_ARRAY_BUFFER, VBO);
     glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(Vertex), &vertices[0], GL_STATIC_DRAW);  
 
@@ -75,6 +80,14 @@ Mesh::Mesh(
     glEnableVertexAttribArray(4);
     glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<void*>(offsetof(Vertex, m_weights)));
 
+    // tangents
+    glEnableVertexAttribArray(5);
+    glVertexAttribPointer(5, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<void*>(offsetof(Vertex, tangent)));
+
+    // bitangents
+    glEnableVertexAttribArray(6);
+    glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<void*>(offsetof(Vertex, bitangent)));
+
     glBindBuffer(GL_ARRAY_BUFFER, 0);
     glBindVertexArray(0);
 
@@ -85,6 +98,44 @@ Mesh::Mesh(
     // std::cout << "\t shininess" << this->material.shininess << std::endl;
 }
 
+void Mesh::setupNormalMaps() {
+    for (int i=0; i + 2 < indices.size(); i+=3){
+        // if (i + 1 > indices.size()) {
+        // }
+        // get 3 vertices for a triangle
+        Vertex& v0 = vertices.at(indices.at(i));
+        Vertex& v1 = vertices.at(indices.at(i+1));
+        Vertex& v2 = vertices.at(indices.at(i+2));
+
+        // Edges of the triangle : position delta
+        glm::vec3 deltaPos1 = v1.position - v0.position;
+        glm::vec3 deltaPos2 = v2.position - v0.position;
+
+        // UV delta
+        glm::vec2 deltaUV1 = v1.textureCoords - v0.textureCoords;
+        glm::vec2 deltaUV2 = v2.textureCoords - v0.textureCoords;
+
+        float r = 1.0f / (deltaUV1.x * deltaUV2.y - deltaUV1.y * deltaUV2.x);
+        glm::vec3 tangent = (deltaPos1 * deltaUV2.y   - deltaPos2 * deltaUV1.y)*r;
+        glm::vec3 bitangent = (deltaPos2 * deltaUV1.x   - deltaPos1 * deltaUV2.x)*r;
+
+        v0.tangent += tangent;
+        v1.tangent += tangent;
+        v2.tangent += tangent;
+
+        v0.bitangent += bitangent;
+        v1.bitangent += bitangent;
+        v2.bitangent += bitangent;
+    }
+
+    for (int i = 0; i < vertices.size(); i++) {
+        // vertices.at(i).tangent = glm::normalize(vertices.at(i).tangent);
+        // // std::cout << "tangent " << glm::to_string(vertices.at(i).tangent) << "\n";
+        // // exit(1);
+        // vertices.at(i).bitangent = glm::normalize(vertices.at(i).bitangent);
+    }
+}
+
 void Mesh::draw(
     Shader* shader,
     glm::vec3 camPos,
@@ -93,10 +144,12 @@ void Mesh::draw(
     auto model = this->getModelMat();
 
     shader->setMat4("model", model);
+    shader->setVec3("viewPos", camPos);
 
     if (textures.size() != 0) {
         unsigned int diffuseNr = 1;
         unsigned int specularNr = 1;
+        unsigned int normalNr = 1;
         for(unsigned int i = 0; i < textures.size(); i++) {
             glActiveTexture(GL_TEXTURE0 + i); // activate proper texture unit before binding
             // retrieve texture number (the N in diffuse_textureN)
@@ -106,11 +159,20 @@ void Mesh::draw(
                 number = std::to_string(diffuseNr++);
             else if(name == "texture_specular")
                 number = std::to_string(specularNr++);
+            else if(name == "texture_normal")
+                number = std::to_string(normalNr++);
 
             std::string shaderTextureName = name + number;
             shader->setInt(shaderTextureName, i);
             glBindTexture(GL_TEXTURE_2D, textures[i].getID());
         }
+
+        if (normalNr == 1) {
+            // never set any normal map texture uniform
+            shader->setBool("has_normal_map", false);
+        } else {
+            shader->setBool("has_normal_map", true);
+        }
     } else {
         // shader->setFloat("shininess", this->material.shininess);
     }
@@ -142,13 +204,15 @@ Model::Model(const std::string& filepath, bool flip_uvs) {
                 aiProcess_FlipUVs | 
                 aiProcess_SplitLargeMeshes | 
                 aiProcess_OptimizeMeshes | 
-                aiProcess_GenBoundingBoxes); // needed to query bounding box of the model later
+                aiProcess_GenBoundingBoxes | // needed to query bounding box of the model later
+                aiProcess_CalcTangentSpace); 
     } else {
         scene = importer.ReadFile(filepath, 
                 aiProcess_Triangulate | // flag to only creates geometry made of triangles
                 aiProcess_SplitLargeMeshes | 
                 aiProcess_OptimizeMeshes | 
-                aiProcess_GenBoundingBoxes); // needed to query bounding box of the model later
+                aiProcess_GenBoundingBoxes | // needed to query bounding box of the model later
+                aiProcess_CalcTangentSpace); 
     }
 
     if(!scene || scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE || !scene->mRootNode) {
@@ -355,6 +419,9 @@ Mesh Model::processMesh(aiMesh *mesh, const aiScene *scene) {
         std::vector<Texture> specularMaps = loadMaterialTextures(material, aiTextureType_SPECULAR);
         textures.insert(textures.end(), specularMaps.begin(), specularMaps.end());
 
+        std::vector<Texture> heightMaps = loadMaterialTextures(material, aiTextureType_HEIGHT);
+        textures.insert(textures.end(), heightMaps.begin(), heightMaps.end());
+
         if(AI_SUCCESS != material->Get(AI_MATKEY_COLOR_DIFFUSE, diffuse_color)) {
             std::cout << "couldn't get diffuse color" << std::endl;
         }
@@ -442,7 +509,7 @@ void Model::extractBoneWeight(std::vector<Vertex>& vertices, aiMesh* mesh, const
 
 std::vector<Texture> Model::loadMaterialTextures(aiMaterial* mat, const aiTextureType& type) {
     std::vector<Texture> textures;
-    // std::cout << "material has " << mat->GetTextureCount(type) << " textures of type " << aiTextureTypeToString(type) << std::endl;
+    std::cout << "material has " << mat->GetTextureCount(type) << " textures of type " << aiTextureTypeToString(type) << std::endl;
     for(unsigned int i = 0; i < mat->GetTextureCount(type); i++) {
         aiString str;
         mat->GetTexture(type, i, &str);
@@ -467,6 +534,9 @@ Texture::Texture(const std::string& filepath, const aiTextureType& type) {
         case aiTextureType_SPECULAR:
             this->type = "texture_specular";
             break;
+        case aiTextureType_HEIGHT:
+            this->type = "texture_normal";
+            break;
         default:
             throw std::invalid_argument(std::string("Unimplemented texture type ") + aiTextureTypeToString(type));
     }

src/client/shaders/deferred_geometry.frag

@@ -1,23 +1,52 @@
 #version 330 core
+
+#define NR_POINT_LIGHTS 32
+
 layout (location = 0) out vec3 gPosition;
 layout (location = 1) out vec3 gNormal;
 layout (location = 2) out vec4 gAlbedoSpec;
+// layout (location = 3) out vec3 gTangentNormal;
 
 in vec3 FragPos;
 in vec3 FragNormal;
 in vec2 TexCoords;
+in mat3 TBN;
 
 uniform sampler2D texture_diffuse1;
 uniform sampler2D texture_specular1;
+uniform sampler2D texture_normal1;
+uniform bool has_normal_map;
 
 void main()
 {    
     // store the fragment position vector in the first gbuffer texture
     gPosition = FragPos;
     // also store the per-fragment normals into the gbuffer
-    gNormal = normalize(FragNormal);
+    if (has_normal_map) {
+        // obtain normal from normal map in range [0,1]
+        gNormal = texture(texture_normal1, TexCoords).rgb;
+        // transform normal vector to range [-1,1]
+        gNormal = gNormal * 2.0 - 1.0;
+        gNormal = normalize(TBN * gNormal);
+        gNormal = normalize(gNormal);
+        // if (gNormal == vec3(0.0, 0.0, 0.0)) {
+        //     gAlbedoSpec.rgb = vec3(1.0, 0.0, 0.0);
+        // } else {
+        //     gAlbedoSpec.rgb = vec3(0.0, 1.0, 0.0);
+        // }
+
+        // gNormal = normalize(TBN * (texture(texture_normal1, TexCoords).rgb * 2.0 - 1.0));
+        // gNormal = vec3(0.0, 1.0, 0.0);
+        // gAlbedoSpec.rgb = texture(texture_normal1, TexCoords).rgb;
+    } else {
+        gNormal = normalize(FragNormal);
+        // gAlbedoSpec.rgb = texture(texture_diffuse1, TexCoords).rgb;
+    }
+
     // and the diffuse per-fragment color
     gAlbedoSpec.rgb = texture(texture_diffuse1, TexCoords).rgb;
     // store specular intensity in gAlbedoSpec's alpha component
     gAlbedoSpec.a = texture(texture_specular1, TexCoords).r;
-}  
+
+    // gTangentNormal = texture(texture_normal, TexCoords).rgb;
+}

src/client/shaders/deferred_geometry.vert

@@ -1,16 +1,22 @@
 #version 330 core
+
+#define NR_POINT_LIGHTS 32
+
 layout (location = 0) in vec3 aPos;
 layout (location = 1) in vec3 aNormal;
 layout (location = 2) in vec2 aTexCoords;
 layout (location = 3) in ivec4 boneIds; 
 layout (location = 4) in vec4 weights;
+layout (location = 5) in vec3 aTangent;
+layout (location = 6) in vec3 aBitangent;
 
 const int MAX_BONES = 100;
 const int MAX_BONE_INFLUENCE = 4;
 
 out vec3 FragPos;
-out vec2 TexCoords;
 out vec3 FragNormal;
+out vec2 TexCoords;
+out mat3 TBN;
 
 uniform mat4 model;
 uniform mat4 viewProj;
@@ -49,9 +55,26 @@ void main()
     vec4 worldPos = model * totalPosition;
     FragPos = worldPos.xyz; 
     TexCoords = aTexCoords;
-
+
+    vec3 normal0 = (model * vec4(aNormal, 1.0)).xyz;
+    vec3 tangent0 = (model * vec4(aTangent, 1.0)).xyz;
+
+    vec3 Normal = normalize(normal0);
+    vec3 Tangent = normalize(tangent0);
+    Tangent = normalize(Tangent - dot(Tangent, Normal) * Normal);
+    vec3 Bitangent = cross(Normal, Tangent);
+    TBN = mat3(Tangent, Bitangent, Normal);
+
     mat3 normalMatrix = transpose(inverse(mat3(model)));
-    FragNormal = normalMatrix * vec3(totalNormal);
+    // vec3 T = normalize(normalMatrix * aTangent);
+    // vec3 B = normalize(normalMatrix * aBitangent);
+    // vec3 N = normalize(normalMatrix * aNormal);
+    // // T = normalize(T - dot(T, N) * N);
+    // // vec3 B = cross(N, T);
+    // 
+    // TBN = mat3(T, B, N);
+
+    FragNormal = normalMatrix * aNormal;
 
     gl_Position = viewProj * worldPos;