feat: assignment 3

data/shaders/fragment.glsl

@@ -1,5 +1,12 @@
+uniform int useTexture;
+uniform sampler2D texSampler;
 varying vec3 fcolor;
+varying vec2 ftexcoord;
 
 void main() {
-	gl_FragColor = vec4(fcolor, 1);
+	if (useTexture == 1) {
+		gl_FragColor = texture2D(texSampler, ftexcoord);
+	} else {
+		gl_FragColor = vec4(1.0, 1.0, 1.0, 1.0);
+	}
 }

data/shaders/vertex.glsl

@@ -1,9 +1,12 @@
 uniform mat4 mvp;
 attribute vec3 vpos;
 attribute vec3 vcolor;
+attribute vec2 vtexcoord;
 varying vec3 fcolor;
+varying vec2 ftexcoord;
 
 void main() {
 	gl_Position = mvp * vec4(vpos, 1);
 	fcolor = vcolor;
+	ftexcoord = vtexcoord;
 }

src/engine.cpp

@@ -10,10 +10,12 @@
 #include "buffer.h"
 #include "camera.h"
 #include "logger.h"
+#include "material.h"
 #include "mesh.h"
 #include "model.h"
 #include "shader.h"
 #include "state.h"
+#include "texture.h"
 #include "vertex.h"
 #include "world.h"
 
@@ -83,8 +85,8 @@ void Engine::initialize()
 
 	// Initialize default shader
 	Logger::info("Loading default shaders...");
-	state::default_shader =
+	state::default_shader = std::make_shared<Shader>(
-	    std::make_shared<Shader>("data/shaders/vertex.glsl", "data/shaders/fragment.glsl");
+	    "data/shaders/vertex.glsl", "data/shaders/fragment.glsl");
 	if (std::strlen(state::default_shader->error()) > 0) {
 		Logger::error(sstr("Failed to initialize shaders: ",
 				   state::default_shader->error()));
@@ -140,9 +142,10 @@ void Engine::setup()
 	world_ = std::make_unique<World>();
 	Logger::info("World created");
 
-	// Create camera
+	// Create camera at position (0, 1, 3) with -20 degrees X rotation
 	camera_ = std::make_shared<Camera>();
-	camera_->set_position(glm::vec3(0.0f, 0.0f, 6.0f));
+	camera_->set_position(glm::vec3(0.0f, 1.0f, 3.0f));
+	camera_->set_rotation(glm::vec3(glm::radians(-20.0f), 0.0f, 0.0f));
 	camera_->set_projection(
 	    glm::perspective(glm::radians(45.0f),
 			     static_cast<float>(screen_width_)
@@ -153,31 +156,79 @@ void Engine::setup()
 	world_->add_entity(camera_);
 	Logger::info("Camera created and added to world");
 
-	// Create triangle mesh
+	// Load textures
-	std::vector<Vertex> vertices = {
+	auto top_texture   = Texture::load("data/textures/top.png");
-	    {{0.0f, 0.5f, 0.0f}, {0.0f, 1.0f, 0.0f}},
+	auto front_texture = Texture::load("data/textures/front.png");
-	    {{-0.5f, -0.5f, 0.0f}, {0.0f, 0.0f, 1.0f}},
-	    {{0.5f, -0.5f, 0.0f}, {1.0f, 0.0f, 0.0f}}};
-	std::vector<uint16_t> indices = {0, 1, 2};
 
-	auto buffer = std::make_shared<Buffer>(vertices, indices);
+	// Create cube mesh with two buffers
 	mesh_ = std::make_shared<Mesh>();
-	mesh_->add_buffer(buffer);
-	Logger::info(sstr("Mesh created with ", vertices.size(),
-			  " vertices and ", indices.size(), " indices"));
 
-	// Create 9 models in a 3x3 grid
+	// Buffer 1: Top and bottom faces
-	for (int row = 0; row < 3; ++row) {
+	std::vector<Vertex> top_bottom_vertices = {
-		for (int col = 0; col < 3; ++col) {
+	    // Top 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}},
+	    // 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(
+	model->set_position(glm::vec3(0.0f, 0.0f, 0.0f));
-			    glm::vec3(-3.0f + static_cast<float>(col) * 3.0f,
-				      0.0f, static_cast<float>(-row) * 3.0f));
 	models_.push_back(model);
 	world_->add_entity(model);
-		}
+
-	}
-	Logger::info(sstr("Created ", models_.size(), " models in scene"));
 	Logger::info("Scene setup complete");
 }
 

src/material.cpp

@@ -0,0 +1,61 @@
+#include "material.h"
+
+#include "../lib/glm/glm.hpp"
+
+#include "shader.h"
+#include "state.h"
+#include "texture.h"
+
+Material::Material(const std::shared_ptr<Texture>& tex,
+		   const std::shared_ptr<Shader>&  shader)
+    : shader_(shader), texture_(tex)
+{
+}
+
+const std::shared_ptr<Shader>& Material::shader() const
+{
+	return shader_ ? shader_ : state::default_shader;
+}
+
+std::shared_ptr<Shader>& Material::shader()
+{
+	return shader_ ? shader_ : state::default_shader;
+}
+
+void Material::set_shader(const std::shared_ptr<Shader>& shader)
+{
+	shader_ = shader;
+}
+
+void Material::prepare()
+{
+	// Activate shader
+	std::shared_ptr<Shader> active_shader = shader();
+	if (!active_shader)
+		return;
+
+	active_shader->use();
+
+	// Set uniform variables
+	const glm::mat4 mvp =
+	    state::projection_matrix * state::view_matrix * state::model_matrix;
+	const int mvp_loc = active_shader->uniform_location("mvp");
+	Shader::set_mat4(mvp_loc, mvp);
+
+	// Set texture-related uniforms
+	const int use_texture_loc =
+	    active_shader->uniform_location("useTexture");
+	if (texture_) {
+		Shader::set_int(use_texture_loc, 1);
+		const int sampler_loc =
+		    active_shader->uniform_location("texSampler");
+		Shader::set_int(sampler_loc, 0); // Texture unit 0
+	} else {
+		Shader::set_int(use_texture_loc, 0);
+	}
+
+	// Bind texture if available
+	if (texture_) {
+		texture_->bind();
+	}
+}

src/material.h

@@ -0,0 +1,35 @@
+#ifndef MATERIAL_H_
+#define MATERIAL_H_
+
+#include <memory>
+
+class Shader;
+class Texture;
+
+class Material {
+public:
+	Material(const std::shared_ptr<Texture>& tex	= nullptr,
+		 const std::shared_ptr<Shader>&	 shader = nullptr);
+	~Material() = default;
+
+	[[nodiscard]] const std::shared_ptr<Shader>& shader() const;
+	[[nodiscard]] std::shared_ptr<Shader>&	     shader();
+	void set_shader(const std::shared_ptr<Shader>& shader);
+
+	[[nodiscard]] const std::shared_ptr<Texture>& texture() const
+	{
+		return texture_;
+	}
+	void set_texture(const std::shared_ptr<Texture>& tex)
+	{
+		texture_ = tex;
+	}
+
+	void prepare();
+
+private:
+	std::shared_ptr<Shader>	 shader_;
+	std::shared_ptr<Texture> texture_;
+};
+
+#endif // MATERIAL_H_

src/mesh.cpp

@@ -1,33 +1,20 @@
 #include "mesh.h"
+
 #include "buffer.h"
-#include "shader.h"
+#include "material.h"
-#include "state.h"
 
 void Mesh::add_buffer(const std::shared_ptr<Buffer>& buffer,
-		      const std::shared_ptr<Shader>& shader)
+		      const Material& material)
 {
 	buffers_.push_back(buffer);
-	shaders_.push_back(shader);
+	materials_.push_back(material);
 }
 
 void Mesh::draw()
 {
-	// Calculate MVP matrix
+	// Draw each buffer with its material
-	glm::mat4 mvp = state::projection_matrix * state::view_matrix
-	    * state::model_matrix;
-
-	// Draw each buffer with its shader
 	for (size_t i = 0; i < buffers_.size(); ++i) {
-		// Use buffer's shader if available, otherwise use default
+		materials_[i].prepare();
-		// shader
+		buffers_[i]->draw(*materials_[i].shader());
-		std::shared_ptr<Shader> shader =
-		    shaders_[i] ? shaders_[i] : state::default_shader;
-
-		if (shader) {
-			shader->use();
-			int mvpLoc = shader->uniform_location("mvp");
-			Shader::set_mat4(mvpLoc, mvp);
-			buffers_[i]->draw(*shader);
-		}
 	}
 }

src/mesh.h

@@ -4,8 +4,9 @@
 #include <memory>
 #include <vector>
 
+#include "material.h"
+
 class Buffer;
-class Shader;
 
 class Mesh {
 public:
@@ -13,7 +14,7 @@ public:
 	~Mesh() = default;
 
 	void add_buffer(const std::shared_ptr<Buffer>& buffer,
-			const std::shared_ptr<Shader>& shader = nullptr);
+			const Material&		       material);
 
 	[[nodiscard]] size_t num_buffers() const
 	{
@@ -28,11 +29,20 @@ public:
 		return buffers_[index];
 	}
 
+	[[nodiscard]] const Material& material(size_t index) const
+	{
+		return materials_[index];
+	}
+	[[nodiscard]] Material& material(size_t index)
+	{
+		return materials_[index];
+	}
+
 	void draw();
 
 private:
 	std::vector<std::shared_ptr<Buffer>> buffers_;
-	std::vector<std::shared_ptr<Shader>> shaders_;
+	std::vector<Material>		     materials_;
 };
 
 #endif // MESH_H_

src/shader.cpp

@@ -10,11 +10,11 @@
 #include "logger.h"
 #include "vertex.h"
 
-Shader::Shader(const std::string& vertexPath, const std::string& fragmentPath)
+Shader::Shader(const std::string& vertex_path, const std::string& fragment_path)
 {
-	const uint32_t vshader = compile_shader(GL_VERTEX_SHADER, vertexPath);
+	const uint32_t vshader = compile_shader(GL_VERTEX_SHADER, vertex_path);
 	const uint32_t fshader =
-	    compile_shader(GL_FRAGMENT_SHADER, fragmentPath);
+	    compile_shader(GL_FRAGMENT_SHADER, fragment_path);
 
 	if (vshader == 0 || fshader == 0) {
 		program_id_ = 0;
@@ -65,6 +65,14 @@ void Shader::setup_attribs() const
 		    loc, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex),
 		    reinterpret_cast<const void*>(offsetof(Vertex, color)));
 	}
+
+	loc = glGetAttribLocation(program_id_, "vtexcoord");
+	if (loc != -1) {
+		glEnableVertexAttribArray(loc);
+		glVertexAttribPointer(
+		    loc, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex),
+		    reinterpret_cast<const void*>(offsetof(Vertex, tex_coord)));
+	}
 }
 
 int Shader::uniform_location(const char* key) const
@@ -141,9 +149,8 @@ uint32_t Shader::compile_shader(uint32_t type, const std::string& source_path)
 		char buffer[1024];
 		glGetShaderInfoLog(shader, sizeof(buffer), nullptr, buffer);
 		error_ = buffer;
-		Logger::error(
+		Logger::error(sstr("Shader compilation failed (",
-		    sstr("Shader compilation failed (", shader_type_name, "): ",
+				   shader_type_name, "): ", buffer));
-			 buffer));
 		glDeleteShader(shader);
 		return 0;
 	}

src/texture.cpp

@@ -0,0 +1,83 @@
+#include "texture.h"
+
+#include <algorithm>
+
+#include "../lib/glew/GL/glew.h"
+#include "../lib/glfw/glfw3.h"
+
+#define STB_IMAGE_IMPLEMENTATION
+#include "../lib/stb/stb_image.h"
+
+#include "logger.h"
+
+Texture::Texture(uint32_t id, const glm::ivec2& size)
+    : id_(id), size_(size)
+{
+}
+
+Texture::~Texture()
+{
+	if (id_ != 0) {
+		glDeleteTextures(1, &id_);
+		Logger::info(sstr("Texture ", id_, " destroyed"));
+	}
+}
+
+std::shared_ptr<Texture> Texture::load(const char* filename)
+{
+	Logger::info(sstr("Loading texture: ", filename));
+
+	// Load image
+	int	 width, height, channels;
+	stbi_uc* pixels =
+	    stbi_load(filename, &width, &height, &channels, STBI_rgb_alpha);
+
+	if (!pixels) {
+		Logger::error(sstr("Failed to load texture: ", filename, " - ",
+				   stbi_failure_reason()));
+		return nullptr;
+	}
+
+	// Flip image vertically (OpenGL expects bottom row first)
+	const int row_size   = width * 4; // 4 channels (RGBA)
+	auto*	  row_buffer = new stbi_uc[row_size];
+	for (int y = 0; y < height / 2; ++y) {
+		stbi_uc* row1 = pixels + y * row_size;
+		stbi_uc* row2 = pixels + (height - 1 - y) * row_size;
+		std::copy(row1, row1 + row_size, row_buffer);
+		std::copy(row2, row2 + row_size, row1);
+		std::copy(row_buffer, row_buffer + row_size, row2);
+	}
+	delete[] row_buffer;
+
+	// Generate OpenGL texture
+	GLuint texture_id;
+	glGenTextures(1, &texture_id);
+	glBindTexture(GL_TEXTURE_2D, texture_id);
+
+	// Upload texture data
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA,
+		     GL_UNSIGNED_BYTE, pixels);
+
+	// Set trilinear filtering
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
+			GL_LINEAR_MIPMAP_LINEAR);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+	// Generate mipmaps
+	glGenerateMipmap(GL_TEXTURE_2D);
+
+	// Free image data
+	stbi_image_free(pixels);
+
+	Logger::info(sstr("Texture loaded successfully: ", filename, " (",
+			  width, "x", height, ", ", channels, " channels)"));
+
+	return std::shared_ptr<Texture>(
+	    new Texture(texture_id, glm::ivec2(width, height)));
+}
+
+void Texture::bind() const
+{
+	glBindTexture(GL_TEXTURE_2D, id_);
+}

src/texture.h

@@ -0,0 +1,35 @@
+#ifndef TEXTURE_H_
+#define TEXTURE_H_
+
+#include <cstdint>
+#include <memory>
+#include <string>
+
+#include "../lib/glm/glm.hpp"
+
+class Texture {
+public:
+	Texture() = delete;
+	~Texture();
+
+	static std::shared_ptr<Texture> load(const char* filename);
+
+	[[nodiscard]] uint32_t id() const
+	{
+		return id_;
+	}
+	[[nodiscard]] const glm::ivec2& size() const
+	{
+		return size_;
+	}
+
+	void bind() const;
+
+private:
+	Texture(uint32_t id, const glm::ivec2& size);
+
+	uint32_t   id_;
+	glm::ivec2 size_;
+};
+
+#endif // TEXTURE_H_

src/vertex.h

@@ -6,6 +6,7 @@
 struct Vertex {
 	glm::vec3 position{0.0f, 0.0f, 0.0f};
 	glm::vec3 color{0.0f, 0.0f, 0.0f};
+	glm::vec2 tex_coord{0.0f, 0.0f};
 };
 
 #endif // VERTEX_H_

ugine3d.vcxproj

@@ -159,15 +159,18 @@
     <ClInclude Include="lib\glew\GL\glew.h" />
     <ClInclude Include="lib\glfw\glfw3.h" />
     <ClInclude Include="lib\glfw\glfw3native.h" />
+    <ClInclude Include="lib\stb\stb_image.h" />
     <ClInclude Include="src\buffer.h" />
     <ClInclude Include="src\camera.h" />
     <ClInclude Include="src\engine.h" />
     <ClInclude Include="src\entity.h" />
     <ClInclude Include="src\logger.h" />
+    <ClInclude Include="src\material.h" />
     <ClInclude Include="src\mesh.h" />
     <ClInclude Include="src\model.h" />
     <ClInclude Include="src\shader.h" />
     <ClInclude Include="src\state.h" />
+    <ClInclude Include="src\texture.h" />
     <ClInclude Include="src\vertex.h" />
     <ClInclude Include="src\world.h" />
   </ItemGroup>
@@ -179,15 +182,17 @@
     <ClCompile Include="src\entity.cpp" />
     <ClCompile Include="src\logger.cpp" />
     <ClCompile Include="src\main.cpp" />
+    <ClCompile Include="src\material.cpp" />
     <ClCompile Include="src\mesh.cpp" />
     <ClCompile Include="src\model.cpp" />
     <ClCompile Include="src\shader.cpp" />
+    <ClCompile Include="src\texture.cpp" />
     <ClCompile Include="src\vertex.cpp" />
     <ClCompile Include="src\world.cpp" />
   </ItemGroup>
   <ItemGroup>
-    <None Include="data\fragment.glsl" />
+    <None Include="data\shaders\fragment.glsl" />
-    <None Include="data\vertex.glsl" />
+    <None Include="data\shaders\vertex.glsl" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">

ugine3d.vcxproj.filters

@@ -19,6 +19,9 @@
     <Filter Include="glew">
       <UniqueIdentifier>{296e1ba9-28bc-4e0b-8d4e-413551edca96}</UniqueIdentifier>
     </Filter>
+    <Filter Include="stb">
+      <UniqueIdentifier>{e3c5a7f2-1d4b-4a9c-8f2e-9b5c8d7a6e4f}</UniqueIdentifier>
+    </Filter>
     <Filter Include="Shaders">
       <UniqueIdentifier>{0628083b-a31c-4825-822c-11b6f933e7bd}</UniqueIdentifier>
     </Filter>
@@ -33,6 +36,9 @@
     <ClInclude Include="lib\glew\GL\glew.h">
       <Filter>glew</Filter>
     </ClInclude>
+    <ClInclude Include="lib\stb\stb_image.h">
+      <Filter>stb</Filter>
+    </ClInclude>
     <ClInclude Include="src\vertex.h">
       <Filter>Source Files</Filter>
     </ClInclude>
@@ -66,6 +72,12 @@
     <ClInclude Include="src\logger.h">
       <Filter>Source Files</Filter>
     </ClInclude>
+    <ClInclude Include="src\material.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
+    <ClInclude Include="src\texture.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="src\main.cpp">
@@ -104,12 +116,18 @@
     <ClCompile Include="src\logger.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="src\material.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="src\texture.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
-    <None Include="data\fragment.glsl">
+    <None Include="data\shaders\fragment.glsl">
       <Filter>Shaders</Filter>
     </None>
-    <None Include="data\vertex.glsl">
+    <None Include="data\shaders\vertex.glsl">
       <Filter>Shaders</Filter>
     </None>
   </ItemGroup>