OpenGL如何基于glfw库进行点线面已解决

GLFW是现在较流行、使用广泛的OpenGL的界面库，而glut库已经比较老了。GLEW是和管理OpenGL函数指针有关的库，因为OpenGL只是一个标准/规范，具体的实现是由驱动开发商针对特定显卡实现的。由于OpenGL驱动版本众多，它大多数函数的位置都无法在编译时确定下来，需要在运行时查询，而GLEW可以解决这些问题。下面就来看下OpenGL是如何基于glfw库实现画点、画线、画三角的。

1、glVertex函数

2、坐标系

代码如下：

#include <GLFW/glfw3.h>
void drawPoint()
｛/* Draw a point */glClearColor (0.0, 0.0, 0.0, 0.0); glClear(GL_COLOR_BUFFER_BIT);glPointSize(2.0f);glBegin(GL_POINTS);glColor3f(1.0, 0.0, 0.0);    // RedglVertex2f(0.0f,0.0f);glVertex2f(0.5f,0.8f);glEnd();
｝
void drawLint()
｛glClearColor (0.0, 0.0, 0.0, 0.0);glClear (GL_COLOR_BUFFER_BIT);glLineWidth(2);//设置线段宽度glBegin(GL_LINES);glColor3f(1.0,0.0,0.0);glVertex2f(0.8,1); //定点坐标范围glVertex2f(0,-1);glEnd();
｝
void drawTriangle()
｛glClearColor (0.0, 0.0, 0.0, 0.0);glClear (GL_COLOR_BUFFER_BIT);glBegin(GL_TRIANGLES);glColor3f(1.0, 0.0, 0.0);    // RedglVertex3f(0.0, 1.0, 0.0);glColor3f(0.0, 1.0, 0.0);    // GreenglVertex3f(-1.0, -1.0, 0.0);glColor3f(0.0, 0.0, 1.0);    // BlueglVertex3f(1.0, -1.0, 0.0);glEnd();
｝
int main(void)
｛GLFWwindow* window;/* Initialize the library */if (!glfwInit())return -1;/* Create a windowed mode window and its OpenGL context */window = glfwCreateWindow(480, 320, "Hello World", NULL, NULL);if (!window)｛glfwTerminate();return -1;｝/* Make the window's context current */glfwMakeContextCurrent(window);/* Loop until the user closes the window */while (!glfwWindowShouldClose(window))｛/*your draw*/// drawPoint();// drawLint();drawTriangle();/* Swap front and back buffers */glfwSwapBuffers(window);/* Poll for and process events */glfwPollEvents();｝glfwTerminate();return 0;
｝

运行效果