feat: load obj

src/engine.cpp

@@ -111,7 +111,7 @@ void Engine::run()
 		const double now	= glfwGetTime();
 		const double delta_time = now - last_update_time_;
 
-		process_input();
+		process_input(delta_time);
 		update(delta_time);
 
 		if (now - last_frame_time_ >= fps_limit) {
@@ -156,78 +156,27 @@ void Engine::setup()
 	world_->add_entity(camera_);
 	Logger::info("Camera created and added to world");
 
-	// Load textures
+	// Load the box_stack model
-	auto top_texture   = Texture::load("data/textures/top.png");
+	auto box_stack_mesh = Mesh::load("data/models/box_stack.obj");
-	auto front_texture = Texture::load("data/textures/front.png");
+	if (box_stack_mesh) {
+		auto box_stack_model = std::make_shared<Model>(box_stack_mesh);
+		box_stack_model->set_position(glm::vec3(-2.0f, 0.0f, 0.0f));
+		models_.push_back(box_stack_model);
+		world_->add_entity(box_stack_model);
+		Logger::info("Box stack model loaded and added to world");
+	}
 
-	// Create cube mesh with two buffers
+	// Load the gunslinger model
-	mesh_ = std::make_shared<Mesh>();
+	auto gunslinger_mesh = Mesh::load("data/models/gunslinger.obj");
-
+	if (gunslinger_mesh) {
-	// Buffer 1: Top and bottom faces
+		auto gunslinger_model =
-	std::vector<Vertex> top_bottom_vertices = {
+		    std::make_shared<Model>(gunslinger_mesh);
-	    // Top face (y = 0.5)
+		gunslinger_model->set_position(glm::vec3(2.0f, 0.0f, 0.0f));
-	    {{-0.5f, 0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 0.0f}},
+		gunslinger_model->set_scale(glm::vec3(0.5f, 0.5f, 0.5f));
-	    {{0.5f, 0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 0.0f}},
+		models_.push_back(gunslinger_model);
-	    {{0.5f, 0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 1.0f}},
+		world_->add_entity(gunslinger_model);
-	    {{-0.5f, 0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 1.0f}},
+		Logger::info("Gunslinger model loaded and added to world");
-	    // Bottom face (y = -0.5)
+	}
-	    {{-0.5f, -0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 0.0f}},
-	    {{0.5f, -0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 0.0f}},
-	    {{0.5f, -0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 1.0f}},
-	    {{-0.5f, -0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 1.0f}}};
-	std::vector<uint16_t> top_bottom_indices = {// Top face
-						    0, 1, 2, 0, 2, 3,
-						    // Bottom face
-						    4, 6, 5, 4, 7, 6};
-
-	auto top_bottom_buffer =
-	    std::make_shared<Buffer>(top_bottom_vertices, top_bottom_indices);
-	Material top_material(top_texture);
-	mesh_->add_buffer(top_bottom_buffer, top_material);
-
-	// Buffer 2: Front, back, left, right faces
-	std::vector<Vertex> side_vertices = {
-	    // Front face (z = 0.5)
-	    {{-0.5f, -0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 0.0f}},
-	    {{0.5f, -0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 0.0f}},
-	    {{0.5f, 0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 1.0f}},
-	    {{-0.5f, 0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 1.0f}},
-	    // Back face (z = -0.5)
-	    {{-0.5f, -0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 0.0f}},
-	    {{-0.5f, 0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 1.0f}},
-	    {{0.5f, 0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 1.0f}},
-	    {{0.5f, -0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 0.0f}},
-	    // Left face (x = -0.5)
-	    {{-0.5f, -0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 0.0f}},
-	    {{-0.5f, -0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 0.0f}},
-	    {{-0.5f, 0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 1.0f}},
-	    {{-0.5f, 0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 1.0f}},
-	    // Right face (x = 0.5)
-	    {{0.5f, -0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 0.0f}},
-	    {{0.5f, 0.5f, -0.5f}, {1.0f, 1.0f, 1.0f}, {1.0f, 1.0f}},
-	    {{0.5f, 0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 1.0f}},
-	    {{0.5f, -0.5f, 0.5f}, {1.0f, 1.0f, 1.0f}, {0.0f, 0.0f}}};
-	std::vector<uint16_t> side_indices = {// Front face
-					      0, 1, 2, 0, 2, 3,
-					      // Back face
-					      4, 5, 6, 4, 6, 7,
-					      // Left face
-					      8, 9, 10, 8, 10, 11,
-					      // Right face
-					      12, 13, 14, 12, 14, 15};
-
-	auto side_buffer =
-	    std::make_shared<Buffer>(side_vertices, side_indices);
-	Material side_material(front_texture);
-	mesh_->add_buffer(side_buffer, side_material);
-
-	Logger::info("Cube mesh created with two buffers");
-
-	// Create model at origin
-	auto model = std::make_shared<Model>(mesh_);
-	model->set_position(glm::vec3(0.0f, 0.0f, 0.0f));
-	models_.push_back(model);
-	world_->add_entity(model);
 
 	Logger::info("Scene setup complete");
 }
@@ -238,22 +187,44 @@ void Engine::start()
 	// Can be used for initialization that needs the scene to be ready
 }
 
-void Engine::process_input()
+void Engine::process_input(const double delta_time)
 {
 	glfwPollEvents();
+
+	if (!camera_) {
+		return;
+	}
+
+	constexpr float camera_speed = 7.5f;
+
+	glm::vec3 forward = glm::vec3(0.0f, 0.0f, -1.0f);
+	glm::vec3 right	  = glm::vec3(1.0f, 0.0f, 0.0f);
+
+	glm::mat4 rotation = glm::mat4(1.0f);
+	rotation	   = glm::rotate(rotation, camera_->rotation().y,
+					 glm::vec3(0.0f, 1.0f, 0.0f));
+	rotation	   = glm::rotate(rotation, camera_->rotation().x,
+					 glm::vec3(1.0f, 0.0f, 0.0f));
+	forward		   = glm::vec3(rotation * glm::vec4(forward, 0.0f));
+	right		   = glm::vec3(rotation * glm::vec4(right, 0.0f));
+
+	const float movement = camera_speed * static_cast<float>(delta_time);
+	if (glfwGetKey(window_, GLFW_KEY_UP) == GLFW_PRESS) {
+		camera_->set_position(camera_->position() + forward * movement);
+	}
+	if (glfwGetKey(window_, GLFW_KEY_DOWN) == GLFW_PRESS) {
+		camera_->set_position(camera_->position() - forward * movement);
+	}
+	if (glfwGetKey(window_, GLFW_KEY_LEFT) == GLFW_PRESS) {
+		camera_->set_position(camera_->position() - right * movement);
+	}
+	if (glfwGetKey(window_, GLFW_KEY_RIGHT) == GLFW_PRESS) {
+		camera_->set_position(camera_->position() + right * movement);
+	}
 }
 
 void Engine::update(const double delta_time)
 {
-	// Update angle for rotation
-	angle_ += 32.0 * delta_time;
-
-	// Update rotation for all models
-	for (auto& model : models_) {
-		model->set_rotation(glm::vec3(
-		    0.0f, glm::radians(static_cast<float>(angle_)), 0.0f));
-	}
-
 	// Update world
 	world_->update(static_cast<float>(delta_time));
 }

src/engine.h

@@ -25,7 +25,7 @@ private:
 	// Lifecycle methods
 	void setup();
 	void start();
-	void process_input();
+	void process_input(const double delta_time);
 	void update(const double delta_time);
 	void render();
 

src/mesh.cpp

@@ -1,7 +1,18 @@
 #include "mesh.h"
 
+#include <filesystem>
+#include <string>
+#include <unordered_map>
+
+#include "../lib/tiny_obj_loader.h"
+
 #include "buffer.h"
+#include "logger.h"
 #include "material.h"
+#include "shader.h"
+#include "state.h"
+#include "texture.h"
+#include "vertex.h"
 
 void Mesh::add_buffer(const std::shared_ptr<Buffer>& buffer,
 		      const Material&		     material)
@@ -10,6 +21,164 @@ void Mesh::add_buffer(const std::shared_ptr<Buffer>& buffer,
 	materials_.push_back(material);
 }
 
+std::shared_ptr<Mesh> Mesh::load(const char*			filename,
+				 const std::shared_ptr<Shader>& shader)
+{
+	Logger::info(sstr("Loading mesh from: ", filename));
+
+	// Load the OBJ file
+	tinyobj::attrib_t		 attrib;
+	std::vector<tinyobj::shape_t>	 shapes;
+	std::vector<tinyobj::material_t> materials;
+	std::string			 warn_err;
+
+	// Get the directory of the OBJ file for loading materials
+	std::filesystem::path obj_path(filename);
+	std::string	      base_dir = obj_path.parent_path().string();
+	if (!base_dir.empty()) {
+		base_dir += "/";
+	}
+
+	if (!tinyobj::LoadObj(&attrib, &shapes, &materials, &warn_err,
+			      filename, base_dir.c_str())) {
+		Logger::error(
+		    sstr("Failed to load OBJ file: ", filename, " - ",
+			 warn_err));
+		return nullptr;
+	}
+
+	if (!warn_err.empty()) {
+		Logger::warn(sstr("TinyObjLoader warning: ", warn_err));
+	}
+
+	// Create the mesh
+	auto mesh = std::make_shared<Mesh>();
+
+	// Cache loaded textures to avoid loading the same texture multiple
+	// times
+	std::unordered_map<std::string, std::shared_ptr<Texture>> texture_cache;
+
+	// Process each shape
+	for (const auto& shape : shapes) {
+		Logger::info(sstr("Processing shape: ", shape.name));
+
+		// Group faces by material
+		std::unordered_map<int, std::vector<Vertex>> material_vertices;
+		std::unordered_map<int, std::vector<uint16_t>> material_indices;
+
+		// Process all faces in this shape
+		size_t index_offset = 0;
+		for (size_t f = 0; f < shape.mesh.num_face_vertices.size();
+		     f++) {
+			int fv		= shape.mesh.num_face_vertices[f];
+			int material_id = shape.mesh.material_ids[f];
+
+			// Process each vertex in the face
+			for (size_t v = 0; v < static_cast<size_t>(fv); v++) {
+				tinyobj::index_t idx =
+				    shape.mesh.indices[index_offset + v];
+
+				Vertex vertex;
+
+				// Position
+				vertex.position.x =
+				    attrib.vertices[3 * idx.vertex_index + 0];
+				vertex.position.y =
+				    attrib.vertices[3 * idx.vertex_index + 1];
+				vertex.position.z =
+				    attrib.vertices[3 * idx.vertex_index + 2];
+
+				// Color (default to white)
+				vertex.color = glm::vec3(1.0f, 1.0f, 1.0f);
+
+				// Texture coordinates
+				if (idx.texcoord_index >= 0) {
+					vertex.tex_coord.x =
+					    attrib.texcoords
+						[2 * idx.texcoord_index + 0];
+					vertex.tex_coord.y = 1.0f
+					    - attrib.texcoords
+						  [2 * idx.texcoord_index
+						   + 1]; // Flip Y
+				}
+
+				material_vertices[material_id].push_back(
+				    vertex);
+				material_indices[material_id].push_back(
+				    static_cast<uint16_t>(
+					material_vertices[material_id].size()
+					- 1));
+			}
+
+			index_offset += fv;
+		}
+
+		// Create buffers for each material
+		for (const auto& [material_id, vertices] : material_vertices) {
+			const auto& indices = material_indices[material_id];
+
+			// Create buffer
+			auto buffer =
+			    std::make_shared<Buffer>(vertices, indices);
+
+			// Create material
+			std::shared_ptr<Texture> texture = nullptr;
+
+			// Load texture if material has one
+			if (material_id >= 0
+			    && material_id
+				< static_cast<int>(materials.size())) {
+				const auto& mat = materials[material_id];
+				std::string texture_name = mat.diffuse_texname;
+
+				// Try ambient texture if diffuse is not
+				// available
+				if (texture_name.empty()) {
+					texture_name = mat.ambient_texname;
+				}
+
+				if (!texture_name.empty()) {
+					// Check cache first
+					auto it =
+					    texture_cache.find(texture_name);
+					if (it != texture_cache.end()) {
+						texture = it->second;
+					} else {
+						// Load texture
+						std::string texture_path =
+						    base_dir + texture_name;
+						texture = Texture::load(
+						    texture_path.c_str());
+						if (texture) {
+							texture_cache
+							    [texture_name] =
+								texture;
+							Logger::info(sstr(
+							    "Loaded texture: ",
+							    texture_path));
+						} else {
+							Logger::warn(sstr(
+							    "Failed to load texture: ",
+							    texture_path));
+						}
+					}
+				}
+			}
+
+			// Use provided shader or default shader
+			auto material_shader =
+			    shader ? shader : state::default_shader;
+			Material mat(texture, material_shader);
+
+			mesh->add_buffer(buffer, mat);
+		}
+	}
+
+	Logger::info(sstr("Mesh loaded successfully with ", mesh->num_buffers(),
+			  " buffers"));
+	return mesh;
+}
+
 void Mesh::draw()
 {
 	// Draw each buffer with its material

src/mesh.h

@@ -7,12 +7,17 @@
 #include "material.h"
 
 class Buffer;
+class Shader;
 
 class Mesh {
 public:
 	Mesh()	= default;
 	~Mesh() = default;
 
+	static std::shared_ptr<Mesh> load(
+	    const char*			     filename,
+	    const std::shared_ptr<Shader>& shader = nullptr);
+
 	void add_buffer(const std::shared_ptr<Buffer>& buffer,
 			const Material&		       material);