OpenGL使用MVP矩阵生成3D效果的物体

#include 
#include 
#include "shader.h"
#include 
#include 
#include 
#include 
#define STB_IMAGE_IMPLEMENTATION
#include "stb_image.h"
void framebuffer_size_callback(GLFWwindow* window, int width, int height);
void processInput(GLFWwindow *window);
const unsigned int SCR_WIDTH = 800;
const unsigned int SCR_HEIGHT = 600;

int main(void)
{
	//初始化glfw并创建窗口
	//-------------------
	glfwInit();
	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
	glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
	GLFWwindow * window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "window", NULL, NULL);
	if (window == NULL)
	{
		std::cout << "Failed to create GLFW window" << std::endl;
		glfwTerminate();
		return -1;
	}
	glfwMakeContextCurrent(window);
	glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);

	//初始化GLAD
	//--------
	if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) 
	{
		std::cout << "Failed to initialize GLAD" << std::endl;
		return -1;
	}

	//创建着色器
	//---------
	Shader ourShader("D:\\OpenGL\\Project1\\4.1.texture.vs", "D:\\OpenGL\\Project1\\4.1.texture.fs");

	//设置顶点坐标，颜色，纹理坐标
	//--------
	float vertices[] = {
		//     ---- 位置 ---- - 纹理坐标 -
		 0.5f,  0.5f, 0.0f,   1.0f, 1.0f, 
		 0.5f, -0.5f, 0.0f,   1.0f, 0.0f, 
		-0.5f, -0.5f, 0.0f,   0.0f, 0.0f, 
		-0.5f,  0.5f, 0.0f,   0.0f, 1.0f 
	};

	//设置EBO索引
	unsigned int indices[] = {
		0, 1, 3, // 第一个三角形
		1, 2, 3  // 第二个三角形
	};

	unsigned int VBO, VAO, EBO;
	glGenVertexArrays(1, &VAO);
	glGenBuffers(1, &VBO);
	glGenBuffers(1, &EBO);


	glBindVertexArray(VAO);
	glBindBuffer(GL_ARRAY_BUFFER, VBO);
	glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);

	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
	glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);

	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)0);
	glEnableVertexAttribArray(0);

	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)(3 * sizeof(float)));
	glEnableVertexAttribArray(1);

	unsigned int texture1, texture2;
	glGenTextures(1, &texture1);
	glBindTexture(GL_TEXTURE_2D, texture1);

	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

	//生成纹理
	int width, height, nrChannels;
	stbi_set_flip_vertically_on_load(true);
	unsigned char * data = stbi_load("D:\\OpenGL\\Project1\\container.jpg", &width, &height, &nrChannels, 0);
	if (data)
	{
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
		glGenerateMipmap(GL_TEXTURE_2D);
	}
	else
	{
		std::cout << "Failed to load texture" << std::endl;
	}
	stbi_image_free(data);

	glGenTextures(1, &texture2);
	glBindTexture(GL_TEXTURE_2D, texture2);

	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	data = stbi_load("D:\\OpenGL\\Project1\\awesomeface.png", &width, &height, &nrChannels, 0);
	if (data)
	{
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
		glGenerateMipmap(GL_TEXTURE_2D);
	}
	else
	{
		std::cout << "Failed to load texture" << std::endl;
	}
	stbi_image_free(data);

	//设置
	ourShader.use();
	ourShader.setInt("texture1", 0);
	ourShader.setInt("texture2", 1);

	while (!glfwWindowShouldClose(window))
	{
		processInput(window);
		glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
		glClear(GL_COLOR_BUFFER_BIT);
		
		glActiveTexture(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_2D, texture1);
		glActiveTexture(GL_TEXTURE1);
		glBindTexture(GL_TEXTURE_2D, texture2);

		ourShader.use();

		glm::mat4 model = glm::mat4(1.0f); // make sure to initialize matrix to identity matrix first
		glm::mat4 view = glm::mat4(1.0f);
		glm::mat4 projection = glm::mat4(1.0f);
		model = glm::rotate(model, glm::radians(-55.0f), glm::vec3(1.0f, 0.0f, 0.0f));//沿X轴旋转-55°
		view = glm::translate(view, glm::vec3(0.0f, 0.0f, -3.0f));//向z轴移动-3
		projection = glm::perspective(glm::radians(45.0f), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);

		unsigned int modelLoc = glGetUniformLocation(ourShader.ID, "model");
		unsigned int viewLoc = glGetUniformLocation(ourShader.ID, "view");

		glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
		glUniformMatrix4fv(viewLoc, 1, GL_FALSE, &view[0][0]);
		ourShader.setMat4("projection", projection);

		glBindVertexArray(VAO);
		glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);


		

		glfwSwapBuffers(window);
		glfwPollEvents();
	}
	glDeleteVertexArrays(1, &VAO);
	glDeleteBuffers(1, &VBO);
	glDeleteBuffers(1, &EBO);

	glfwTerminate();
	return 0;


}
void processInput(GLFWwindow *window)
{
	if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
		glfwSetWindowShouldClose(window, true);
}
void framebuffer_size_callback(GLFWwindow* window, int width, int height)
{

	glViewport(0, 0, width, height);
}

顶点着色器

#version 330 core
layout (location = 0) in vec3 aPos;
layout (location = 1) in vec2 aTexCoord;

out vec2 TexCoord;

uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;

void main()
{
	gl_Position = projection * view * model * vec4(aPos, 1.0);
	TexCoord = vec2(aTexCoord.x, aTexCoord.y);
}

片元着色器

#version 330 core
out vec4 FragColor;

in vec2 TexCoord;

// texture samplers
uniform sampler2D texture1;
uniform sampler2D texture2;

void main()
{

	FragColor = mix(texture(texture1, TexCoord), texture(texture2, TexCoord), 0.2);
}