OpenGL学习笔记-2：基于GLFW在windows系统下创建一个OpenGL窗口

1>glew32s.lib(glew.obj) : error LNK2019: unresolved external symbol __imp__glGetIntegerv@8 referenced in function _glewContextInit@0
1>glew32s.lib(glew.obj) : error LNK2019: unresolved external symbol __imp__glGetString@4 referenced in function _glewContextInit@0
1>glew32s.lib(glew.obj) : error LNK2019: unresolved external symbol __imp__wglGetCurrentDC@0 referenced in function _wglewGetExtension@4
1>glew32s.lib(glew.obj) : error LNK2019: unresolved external symbol __imp__wglGetProcAddress@4 referenced in function __glewInit_GL_3DFX_tbuffer

#define GLEW_STATIC
#include<GL/glew.h>
#include<GLFW/glfw3.h>


#include<iostream>

using namespace std;

int main()
{   //init glfw
	glfwInit();
	//glfwWindowHint funciton 
	//@param 1 : settings 
	//@param 2 : setting value int
	//set opengl version
	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
	//set the opengl use core-profil mode
	glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
	//The OS only supports forward-compatible core profile contexts for OpenGL versions 3.2 and later. Before creating an OpenGL context of version 3.2 or later you must set the GLFW_OPENGL_FORWARD_COMPAT and GLFW_OPENGL_PROFILE hints accordingly. OpenGL 3.0 and 3.1 contexts are not supported at all on macOS.
	glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
	//glfwCreateWindow function
	//@param 1 : the width of window
	//@param 2 : the height of window
	//@param 3 : UTF-8 encoded window title
	//@param 4 : The monitor to use for full screen mode, or NULL for windowed mode.
	//@param 5 : The window whose context to share resources with, or NULL to not share resources.
	GLFWwindow* window = glfwCreateWindow(800, 600, "LearnOpenGL", NULL, NULL);
	if (window == NULL)
	{
		std::cout << "Failed to create GLFW window" << std::endl;
		glfwTerminate();
		return -1;
	}
	//glfwCreateWindow function
	//makes the OpenGL or OpenGL ES context of the specified window current on the calling thread. 
	glfwMakeContextCurrent(window);

	//有些显卡的驱动程序不能正确给出所支持的扩展信息，导致GLEW不能正确获取某些函数的入口地址
	glewExperimental = GLU_TRUE;
	if (glewInit() != GLEW_OK)
	{
		std::cout << "Failed to glewInit" << std::endl;
		return -1;
	}
	//左下角（0.0）
	glViewport(0, 0, 800, 600);

	while (!glfwWindowShouldClose(window))
	{
		//glfwSwapBuffers function
		//This function swaps the front and back buffers of the specified window when rendering with OpenGL or OpenGL ES.
		glfwSwapBuffers(window);
		//glfwPollEvents function
		//This function processes only those events that are already in the event queue and then returns immediately.
		glfwPollEvents();
	}
	//glfwTerminate function
	//This function destroys all remaining windows and cursors, restores any modified gamma ramps and frees any other allocated resources. 
	glfwTerminate();
	return 0;
}