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使用Nuget极速搭建OpenGL环境(VS + GLFW + GLEW)

  1. 下载GLFW

image.png 2. 下载GLEW image.png 3. 最后的配置

image.png 链接器 >> 常规 >> 附加库目录 添加:

您的项目路径\packages\glew.1.9.0.1\build\native\lib\v110\x64\Release\static

链接器 >> 输入 >> 附加依赖项 添加:

glew.lib opengl32.lib


一个标准的测试工程: main.cpp

#include <iostream>

// GLEW
#define GLEW_STATIC
#include <GL/glew.h>

// GLFW
#include <GLFW/glfw3.h>

// Other includes
#include "Shader.h"


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

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

// The MAIN function, from here we start the application and run the game loop
int main()
{
	// 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
	glViewport(0, 0, WIDTH, HEIGHT);


	// Build and compile our shader program
	Shader ourShader("default.vs", "default.frag");


	// Set up vertex data (and buffer(s)) and attribute pointers
	GLfloat vertices[] = {
		// Positions         // Colors
		0.5f, -0.5f, 0.0f,   1.0f, 0.0f, 0.0f,  // Bottom Right
	   -0.5f, -0.5f, 0.0f,   0.0f, 1.0f, 0.0f,  // Bottom Left
		0.0f,  0.5f, 0.0f,   0.0f, 0.0f, 1.0f   // Top 
	};
	GLuint VBO, VAO;
	glGenVertexArrays(1, &VAO);
	glGenBuffers(1, &VBO);
	// 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);


	// Position attribute
	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLvoid*)0);
        // param 0 对应 vertext shader 中的layout(location = 0) 
        // 从VBO中传出数据到shader中
	glEnableVertexAttribArray(0);
	// Color attribute
	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
        // 1号栏位
	glEnableVertexAttribArray(1);

	glBindVertexArray(0); // Unbind VAO


	// 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 the triangle
		ourShader.Use();
		glBindVertexArray(VAO);
		glDrawArrays(GL_TRIANGLES, 0, 3);
		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);
	// 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);
}
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Shader.h

#ifndef SHADER_H
#define SHADER_H

#include <string>
#include <fstream>
#include <sstream>
#include <iostream>

#include <GL/glew.h>

class Shader
{
public:
	GLuint Program;
	// Constructor generates the shader on the fly
	Shader(const GLchar* vertexPath, const GLchar* fragmentPath)
	{
		// 1. Retrieve the vertex/fragment source code from filePath
		std::string vertexCode;
		std::string fragmentCode;
		std::ifstream vShaderFile;
		std::ifstream fShaderFile;
		// ensures ifstream objects can throw exceptions:
		vShaderFile.exceptions(std::ifstream::badbit);
		fShaderFile.exceptions(std::ifstream::badbit);
		try
		{
			// Open files
			vShaderFile.open(vertexPath);
			fShaderFile.open(fragmentPath);
			std::stringstream vShaderStream, fShaderStream;
			// Read file's buffer contents into streams
			vShaderStream << vShaderFile.rdbuf();
			fShaderStream << fShaderFile.rdbuf();
			// close file handlers
			vShaderFile.close();
			fShaderFile.close();
			// Convert stream into string
			vertexCode = vShaderStream.str();
			fragmentCode = fShaderStream.str();
		}
		catch (std::ifstream::failure e)
		{
			std::cout << "ERROR::SHADER::FILE_NOT_SUCCESFULLY_READ" << std::endl;
		}
		const GLchar* vShaderCode = vertexCode.c_str();
		const GLchar * fShaderCode = fragmentCode.c_str();
		// 2. Compile shaders
		GLuint vertex, fragment;
		GLint success;
		GLchar infoLog[512];
		// Vertex Shader
		vertex = glCreateShader(GL_VERTEX_SHADER);
		glShaderSource(vertex, 1, &vShaderCode, NULL);
		glCompileShader(vertex);
		// Print compile errors if any
		glGetShaderiv(vertex, GL_COMPILE_STATUS, &success);
		if (!success)
		{
			glGetShaderInfoLog(vertex, 512, NULL, infoLog);
			std::cout << "ERROR::SHADER::VERTEX::COMPILATION_FAILED\n" << infoLog << std::endl;
		}
		// Fragment Shader
		fragment = glCreateShader(GL_FRAGMENT_SHADER);
		glShaderSource(fragment, 1, &fShaderCode, NULL);
		glCompileShader(fragment);
		// Print compile errors if any
		glGetShaderiv(fragment, GL_COMPILE_STATUS, &success);
		if (!success)
		{
			glGetShaderInfoLog(fragment, 512, NULL, infoLog);
			std::cout << "ERROR::SHADER::FRAGMENT::COMPILATION_FAILED\n" << infoLog << std::endl;
		}
		// Shader Program
		this->Program = glCreateProgram();
		glAttachShader(this->Program, vertex);
		glAttachShader(this->Program, fragment);
		glLinkProgram(this->Program);
		// Print linking errors if any
		glGetProgramiv(this->Program, GL_LINK_STATUS, &success);
		if (!success)
		{
			glGetProgramInfoLog(this->Program, 512, NULL, infoLog);
			std::cout << "ERROR::SHADER::PROGRAM::LINKING_FAILED\n" << infoLog << std::endl;
		}
		// Delete the shaders as they're linked into our program now and no longer necessery
		glDeleteShader(vertex);
		glDeleteShader(fragment);

	}
	// Uses the current shader
	void Use()
	{
		glUseProgram(this->Program);
	}
};

#endif
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顶点着色器:

#version 330 core
layout (location = 0) in vec3 position;
layout (location = 1) in vec3 color;

out vec3 ourColor;

void main()
{
    gl_Position = vec4(position, 1.0f);
    ourColor = color;
}
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片元着色器:

#version 330 core
in vec3 ourColor;

out vec4 color;

void main()
{
    color = vec4(ourColor, 1.0f);
}
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结果:

image.png

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