Readadd obj loading

examples/dev_testing/src/main.cpp

@@ -171,9 +171,15 @@ int main(int argc, char *argv[]) {
     se::gfx::Material material(white_texture, 1.f, 0.f, 0.f, 0.f, 0.f);
 
     // Create the entity and add the model component to it.
-    auto entity = std::make_shared<simpleengine::Entity>();
+    /* auto entity = std::make_shared<simpleengine::Entity>();
     entity->add_component<se::ModelComponent>(cube_vertices, cube_indicies, material, true);
-    entity->translate(3.5f, 0.f, 0.f);
+    entity->translate(3.5f, 0.f, 0.f); */
+
+    //auto entity = std::make_shared<se::gfx::M>(game.get_window(), core_shader, white_texture, "examples/dev_testing/resources/dragon.obj");
+    auto entity = std::make_shared<simpleengine::Entity>();
+    se::gfx::Model model(material, "examples/dev_testing/resources/dragon.obj");
+    entity->add_component<se::ModelComponent>(model);
+    entity->translate(5.f, 0.f, 0.f);
 
     // Create a renderer and submit the entity into it.
     auto renderer  = std::make_shared<se::gfx::Renderer>(game.get_window(), core_shader);

include/simpleengine/gfx/model.h

@@ -30,6 +30,8 @@ namespace simpleengine::gfx {
 
         Model(std::vector<LitVertex> vertices, std::vector<GLuint> indicies, Material material);
         Model(std::vector<LitVertex> vertices, std::vector<GLuint> indicies = std::vector<GLuint>(), std::optional<Material> material = std::nullopt);
+        Model(Material material, std::string filename);
+        Model(Material material, std::ifstream file_stream);
 
         virtual void destroy() override;
 
@@ -44,5 +46,10 @@ namespace simpleengine::gfx {
          *
          */
         void calculate_normals();
+
+    private:
+        void process_vertex(const std::vector<std::string>& vertex_data, const std::vector<glm::vec2>& in_textures,
+            const std::vector<glm::vec3>& in_normals, std::vector<GLuint>& out_indicies, 
+            std::vector<glm::vec2>& out_textures, std::vector<glm::vec3>& out_normals);
     };
 }

src/gfx/model.cpp

@@ -16,6 +16,111 @@ namespace simpleengine::gfx {
 
     }
 
+    Model::Model(Material material,std::string filename) :
+            Model(material, std::ifstream(filename, std::ios::in | std::ios::binary)) {
+
+    }
+
+    std::vector<std::string> split_string(std::string str, const char delim) {
+        std::istringstream ss(str);
+
+        std::vector<std::string> tokens;
+        size_t pos = 0;
+        std::string token;
+        while ((pos = str.find(delim)) != std::string::npos) {
+            token = str.substr(0, pos);
+            tokens.push_back(token);
+            str.erase(0, pos + 1);
+        }
+        tokens.push_back(str);
+
+        return tokens;
+    }
+
+    Model::Model(Material material, std::ifstream file_stream) :
+            vbo(gfx::VBO::init(GL_ARRAY_BUFFER, false)), ebo(gfx::VBO::init(GL_ELEMENT_ARRAY_BUFFER, false)),
+            vao(gfx::VAO::init()), material(material) {
+
+        if (!file_stream.is_open()) {
+            std::cerr << "File stream that was given to ObjModel::ObjModel is not open!" << std::endl;
+            throw std::runtime_error("Failed to open ObjModel model file");
+        }
+
+        // The vertices, texture coords, and normals that were read from the obj file
+        // these are not in a particular order.
+        std::vector<glm::vec3> obj_vertices;
+        std::vector<glm::vec2> obj_textures;
+        std::vector<glm::vec3> obj_normals;
+
+        // The texture coords and normals that have been sorted.
+        std::vector<glm::vec2> textures;
+        std::vector<glm::vec3> normals;
+
+        // Read the vertices, texture coords, and normals. Break when run into indices
+        std::string line;
+        while (std::getline(file_stream, line)) {
+            std::vector<std::string> line_tokens = split_string(line, ' ');
+
+            if (line_tokens.front() == "v") {
+                //glm::vec3 vertex(stof(line_tokens[1]), stof(line_tokens[2]), stof(line_tokens[3]));
+                obj_vertices.emplace_back(stof(line_tokens[1]), stof(line_tokens[2]), stof(line_tokens[3]));
+            } else if (line_tokens.front() == "vt") {
+                obj_textures.emplace_back(stof(line_tokens[1]), stof(line_tokens[2]));
+            } else if (line_tokens.front() == "vn") {
+                obj_normals.emplace_back(stof(line_tokens[1]), stof(line_tokens[2]), stof(line_tokens[3]));
+            } else if (line_tokens.front() == "f") {
+                auto size = obj_vertices.size();
+                textures.resize(size);
+                normals.resize(size);
+                break;
+            }
+        }
+
+        // Process the indicies. This will sort everything for storing inside of the Vertex list.
+        do {
+            if (!line.starts_with("f")) {
+                continue;
+            }
+            std::vector<std::string> line_tokens = split_string(line, ' ');
+            std::vector<std::string> vertex1 = split_string(line_tokens[1], '/');
+            std::vector<std::string> vertex2 = split_string(line_tokens[2], '/');
+            std::vector<std::string> vertex3 = split_string(line_tokens[3], '/');
+            
+            process_vertex(vertex1, obj_textures, obj_normals, indicies, textures, normals);
+            process_vertex(vertex2, obj_textures, obj_normals, indicies, textures, normals);
+            process_vertex(vertex3, obj_textures, obj_normals, indicies, textures, normals);
+        } while (std::getline(file_stream, line));
+        
+        file_stream.close();
+
+        const int texture_id = 0;
+
+        std::cout << "Texture ID: " << texture_id << std::endl;
+
+        // Insert everything into lit_vertices.
+        for (int i = 0; i < obj_vertices.size(); i++) {
+            vertices.emplace_back(simpleengine::Vectorf(obj_vertices.at(i)), glm::vec3(1.f), textures.at(i), normals.at(i), texture_id);
+        }
+    }
+
+    void Model::process_vertex(const std::vector<std::string>& vertex_data, const std::vector<glm::vec2>& in_textures,
+            const std::vector<glm::vec3>& in_normals, std::vector<GLuint>& out_indicies, 
+            std::vector<glm::vec2>& out_textures, std::vector<glm::vec3>& out_normals) {
+        
+        // Get the index the current vertex and put it in indicies
+        int currentVertexIndex = stoi(vertex_data[0]) - 1;
+        out_indicies.push_back(currentVertexIndex);
+
+        // Read texture coords
+        glm::vec2 current_tex = in_textures.at(stoi(vertex_data[1]) - 1);
+        current_tex.y = 1 - current_tex.y;
+        out_textures.at(currentVertexIndex) = current_tex;
+
+        // Read normals
+        glm::vec3 current_norm = in_normals.at(stoi(vertex_data[2]) - 1);
+        out_normals.at(currentVertexIndex) = current_norm;
+    }
+
     void Model::destroy() {
         this->ebo.destroy();
         this->vbo.destroy();