利用GLFW和GLEW搭建OpenGL开发环境

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1. 下载相应的头文件和库文件

GLEW：http://glew.sourceforge.net/index.html

GLFW：http://www.glfw.org/download.html

得到glew-2.0.0-win32.zip和glfw-3.2.1.bin.WIN32.zip，这里我们采用静态链接库的方式， IDE采用的是Visual Studio 2013，用32位库文件。

(1)头文件：在本地创建文件夹OpenGL，在OpenGL下创建inlcude文件夹，然后将\glfw-3.2.1.bin.WIN32\include下的GLFW拷贝到inlcude里，并将\glew-2.0.0\include中的GL也拷贝到include文件夹中。

(2)LIB文件：将\glfw-3.2.1.bin.WIN32\lib-vc2013下的所有文件拷贝到C:\Program Files (x86)\Windows Kits\8.1\Lib\winv6.3\um\x86，同时将\glew-2.0.0\lib\Release\Win32下的所有文件也拷贝到C:\Program Files (x86)\Windows Kits\8.1\Lib\winv6.3\um\x86。

2.打开VS2013，新建工程

建立一个Win32控制台程序，同时勾选空项目的选项

然后添加一个.cpp文件编写主程序

3.添加GLFW和GLEW的头文件包含目录，右击工程“HelloTriangle”，选择“属性”，如下图，选择“VC++ 目录”。

选择OpenGL\include文件夹

4.将LIB文件名添加到工程

5.编写OpenGL应用程序

6.运行

7.代码

#include 

// GLEW
#define GLEW_STATIC
#include 

// GLFW
#include 


// Function prototypes
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);

// Window dimensions
const GLuint WIDTH = 800, HEIGHT = 600;

// Shaders
const GLchar* vertexShaderSource = "#version 330 core\n"
"layout (location = 0) in vec3 position;\n"
"void main()\n"
"{\n"
"gl_Position = vec4(position.x, position.y, position.z, 1.0);\n"
"}\0";
const GLchar* fragmentShaderSource = "#version 330 core\n"
"out vec4 color;\n"
"void main()\n"
"{\n"
"color = vec4(1.0f, 0.5f, 0.2f, 1.0f);\n"
"}\n\0";

// The MAIN function, from here we start the application and run the game loop
int main()
{
	std::cout << "Starting GLFW context, OpenGL 3.3" << std::endl;
	// Init GLFW
	glfwInit();
	// Set all the required options for GLFW
	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
	glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
	glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);

	// Create a GLFWwindow object that we can use for GLFW's functions
	GLFWwindow* window = glfwCreateWindow(WIDTH, HEIGHT, "LearnOpenGL", nullptr, nullptr);
	glfwMakeContextCurrent(window);

	// Set the required callback functions
	glfwSetKeyCallback(window, key_callback);

	// Set this to true so GLEW knows to use a modern approach to retrieving function pointers and extensions
	glewExperimental = GL_TRUE;
	// Initialize GLEW to setup the OpenGL Function pointers
	glewInit();

	// Define the viewport dimensions
	int width, height;
	glfwGetFramebufferSize(window, &width, &height);
	glViewport(0, 0, width, height);


	// Build and compile our shader program
	// Vertex shader
	GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
	glShaderSource(vertexShader, 1, &vertexShaderSource, NULL);
	glCompileShader(vertexShader);
	// Check for compile time errors
	GLint success;
	GLchar infoLog[512];
	glGetShaderiv(vertexShader, GL_COMPILE_STATUS, &success);
	if (!success)
	{
		glGetShaderInfoLog(vertexShader, 512, NULL, infoLog);
		std::cout << "ERROR::SHADER::VERTEX::COMPILATION_FAILED\n" << infoLog << std::endl;
	}
	// Fragment shader
	GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
	glShaderSource(fragmentShader, 1, &fragmentShaderSource, NULL);
	glCompileShader(fragmentShader);
	// Check for compile time errors
	glGetShaderiv(fragmentShader, GL_COMPILE_STATUS, &success);
	if (!success)
	{
		glGetShaderInfoLog(fragmentShader, 512, NULL, infoLog);
		std::cout << "ERROR::SHADER::FRAGMENT::COMPILATION_FAILED\n" << infoLog << std::endl;
	}
	// Link shaders
	GLuint shaderProgram = glCreateProgram();
	glAttachShader(shaderProgram, vertexShader);
	glAttachShader(shaderProgram, fragmentShader);
	glLinkProgram(shaderProgram);
	// Check for linking errors
	glGetProgramiv(shaderProgram, GL_LINK_STATUS, &success);
	if (!success) {
		glGetProgramInfoLog(shaderProgram, 512, NULL, infoLog);
		std::cout << "ERROR::SHADER::PROGRAM::LINKING_FAILED\n" << infoLog << std::endl;
	}
	glDeleteShader(vertexShader);
	glDeleteShader(fragmentShader);


	// Set up vertex data (and buffer(s)) and attribute pointers
	//GLfloat vertices[] = {
	//  // First triangle
	//   0.5f,  0.5f,  // Top Right
	//   0.5f, -0.5f,  // Bottom Right
	//  -0.5f,  0.5f,  // Top Left 
	//  // Second triangle
	//   0.5f, -0.5f,  // Bottom Right
	//  -0.5f, -0.5f,  // Bottom Left
	//  -0.5f,  0.5f   // Top Left
	//}; 
	GLfloat vertices[] = {
		0.5f, 0.5f, 0.0f,  // Top Right
		0.5f, -0.5f, 0.0f,  // Bottom Right
		-0.5f, -0.5f, 0.0f,  // Bottom Left
		-0.5f, 0.5f, 0.0f   // Top Left 
	};
	GLuint indices[] = {  // Note that we start from 0!
		0, 1, 3,  // First Triangle
		1, 2, 3   // Second Triangle
	};
	GLuint VBO, VAO, EBO;
	glGenVertexArrays(1, &VAO);
	glGenBuffers(1, &VBO);
	glGenBuffers(1, &EBO);
	// Bind the Vertex Array Object first, then bind and set vertex buffer(s) and attribute pointer(s).
	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, 3 * sizeof(GLfloat), (GLvoid*)0);
	glEnableVertexAttribArray(0);

	glBindBuffer(GL_ARRAY_BUFFER, 0); // Note that this is allowed, the call to glVertexAttribPointer registered VBO as the currently bound vertex buffer object so afterwards we can safely unbind

	glBindVertexArray(0); // Unbind VAO (it's always a good thing to unbind any buffer/array to prevent strange bugs), remember: do NOT unbind the EBO, keep it bound to this VAO


	// Uncommenting this call will result in wireframe polygons.
	//glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);

	// Game loop
	while (!glfwWindowShouldClose(window))
	{
		// Check if any events have been activiated (key pressed, mouse moved etc.) and call corresponding response functions
		glfwPollEvents();

		// Render
		// Clear the colorbuffer
		glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
		glClear(GL_COLOR_BUFFER_BIT);

		// Draw our first triangle
		glUseProgram(shaderProgram);
		glBindVertexArray(VAO);
		//glDrawArrays(GL_TRIANGLES, 0, 6);
		glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
		glBindVertexArray(0);

		// Swap the screen buffers
		glfwSwapBuffers(window);
	}
	// Properly de-allocate all resources once they've outlived their purpose
	glDeleteVertexArrays(1, &VAO);
	glDeleteBuffers(1, &VBO);
	glDeleteBuffers(1, &EBO);
	// Terminate GLFW, clearing any resources allocated by GLFW.
	glfwTerminate();
	return 0;
}

// Is called whenever a key is pressed/released via GLFW
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode)
{
	if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
		glfwSetWindowShouldClose(window, GL_TRUE);
}