VS2012下基于Glut OpenGL GL_TRIANGLE_FAN示例程序：

在VS2012下使用glut GL_TRIANGLE_FAN绘制三角形示例程序，绘制的是多个三角形，效果如下图所示，按PC的UP,DOWN,LEFT,RIGHT按键可以从不同的角度查看该图形：

GL_TRIANGLE_FAN对序列点生成三角形的处理方式参考下图与http://blog.youkuaiyun.com/yearafteryear/article/details/9059795就可以看得很清楚：

源代码：

// GlutTriangleFanDemo.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <gl/glut.h>
#include <math.h>
//圆周率宏
#define GL_PI 3.1415f
//获取屏幕的宽度
GLint SCREEN_WIDTH=0;
GLint SCREEN_HEIGHT=0;
//设置程序的窗口大小
GLint windowWidth=400;
GLint windowHeight=300;
//绕x轴旋转角度
GLfloat xRotAngle=0.0f;
//绕y轴旋转角度
GLfloat yRotAngle=0.0f;
//显示回调函数
void renderScreen(void){
    GLfloat x,y,z,angle;
    //把整个窗口清理为当前清理颜色：黑色
    glClear(GL_COLOR_BUFFER_BIT);
    //将当前Matrix状态入栈
    glPushMatrix();
    //坐标系绕x轴旋转xRotAngle
    glRotatef(xRotAngle,1.0f,0.0f,0.0f);
    //坐标系绕y轴旋转yRotAngle
    glRotatef(yRotAngle,0.0f,1.0f,0.0f);

	//进行平滑处理　
	glEnable(GL_POINT_SMOOTH);
	glHint(GL_POINT_SMOOTH,GL_NICEST);
	glEnable(GL_LINE_SMOOTH);
	glHint(GL_LINE_SMOOTH,GL_NICEST);

	//使用白色绘制坐标系
	glColor3f(1.0f,1.0f,1.0f);
	//绘制坐标系
	glBegin(GL_LINES);
		glVertex3f(-80.0f,0.0f,0.0f);
		glVertex3f(80.0f,0.0f,0.0f);
		glVertex3f(0.0f,-80.0f,0.0f);
		glVertex3f(0.0f,80.0f,0.0f);
		glVertex3f(0.0f,0.0f,-80.0f);
		glVertex3f(0.0f,0.0f,80.0f);
	glEnd();

	glPushMatrix();
	glTranslatef(80.0f,0.0f,0.0f);
	glRotatef(90.0f,0.0f,1.0f,0.0f);
	glutWireCone(3,6,10,10);
	glPopMatrix();

	glPushMatrix();
	glTranslatef(0.0f,80.0f,0.0f);
	glRotatef(-90.0f,1.0f,0.0f,0.0f);
	glutWireCone(3,6,10,10);
	glPopMatrix();

	glPushMatrix();
	glTranslatef(0.0f,0.0f,80.0f);
	glRotatef(90.0f,0.0f,0.0f,1.0f);
	glutWireCone(3,6,10,10);
	glPopMatrix();

	//坐标系平移到(-50.0f,0.0f,00.0f)
	glPushMatrix();
	glTranslatef(-50.0f,0.0f,00.0f);
	//白色绘制五个顶点
	glColor3f(1.0f,1.0f,1.0f);
	glPointSize(5.0f);
	glBegin(GL_POINTS);
		glVertex3f(0.0f,0.0f,0.0f);
		glVertex3f(25.0f,25.0f,0.0f);
		glVertex3f(0.0f,50.0f,0.0f);
		glVertex3f(-25.0f,25.0f,0.0f);
		glVertex3f(-25.0f,0.0f,0.0f);
	glEnd();
	//GL_FLAT使用单色模式填充三角形 
	//GL_SMOOTH使用颜色平滑变换模式填充三角形 
	glShadeModel(GL_FLAT);
	//使用GL_TRIANGLE_FAN绘制三角形
	glBegin(GL_TRIANGLE_FAN);
		//使用红色绘制第一个三角形
		glColor3f(1.0f,0.0f,0.0f);
		glVertex3f(0.0f,0.0f,0.0f);
		glVertex3f(25.0f,25.0f,0.0f);
		glVertex3f(0.0f,50.0f,0.0f);
		//使用绿色绘制第二个三角形
		glColor3f(0.0f,1.0f,0.0f);
		glVertex3f(-25.0f,25.0f,0.0f);
		//使用蓝色绘制第三个三角形
		glColor3f(0.0f,0.0f,1.0f);
		glVertex3f(-25.0f,0.0f,0.0f);
	//结束GL_TRIANGLE_FAN绘制三角形
	glEnd();
	glPopMatrix();
	
	//坐标系平移到(50.0f,0.0f,00.0f)
	glPushMatrix();
	glTranslatef(50.0f,0.0f,00.0f);
	//白色绘制五个顶点
	glColor3f(1.0f,1.0f,1.0f);
	glPointSize(5.0f);
	glBegin(GL_POINTS);
		glVertex3f(0.0f,0.0f,0.0f);
		glVertex3f(25.0f,25.0f,0.0f);
		glVertex3f(0.0f,50.0f,0.0f);
		glVertex3f(-25.0f,25.0f,0.0f);
		glVertex3f(-25.0f,0.0f,0.0f);
	glEnd();
	//GL_FLAT使用单色模式填充三角形 
	//GL_SMOOTH使用颜色平滑变换模式填充三角形 
	glShadeModel(GL_SMOOTH);
	//使用GL_TRIANGLE_FAN绘制三角形
	glBegin(GL_TRIANGLE_FAN);
		//使用红色绘制第一个三角形
		glColor3f(1.0f,0.0f,0.0f);
		glVertex3f(0.0f,0.0f,0.0f);
		glVertex3f(25.0f,25.0f,0.0f);
		glVertex3f(0.0f,50.0f,0.0f);
		//使用绿色绘制第二个三角形
		glColor3f(0.0f,1.0f,0.0f);
		glVertex3f(-25.0f,25.0f,0.0f);
		//使用蓝色绘制第三个三角形
		glColor3f(0.0f,0.0f,1.0f);
		glVertex3f(-25.0f,0.0f,0.0f);
	//结束GL_TRIANGLE_FAN绘制三角形
	glEnd();
	glPopMatrix();

	
    //恢复压入栈的Matrix
    glPopMatrix();
    //交换两个缓冲区的指针
    glutSwapBuffers();
}
//设置Redering State 
void setupRederingState(void){
    //设置清理颜色为黑色
    glClearColor(0.0f,0.0,0.0,1.0f);
    //设置绘画颜色为绿色
    glColor3f(0.0f,1.0f,0.0f);
}
//窗口大小变化回调函数
void changSize(GLint w,GLint h){
    //横宽比率
    GLfloat ratio;
    //设置坐标系为x(-100.0f,100.0f)、y(-100.0f,100.0f)、z(-100.0f,100.0f)
    GLfloat coordinatesize=100.0f;
    //窗口宽高为零直接返回
    if((w==0)||(h==0))
        return;
    //设置视口和窗口大小一致
    glViewport(0,0,w,h);
    //对投影矩阵应用随后的矩阵操作
    glMatrixMode(GL_PROJECTION);
    //重置当前指定的矩阵为单位矩阵　
    glLoadIdentity();
    ratio=(GLfloat)w/(GLfloat)h;
    //正交投影
    if(w<h)
        glOrtho(-coordinatesize,coordinatesize,-coordinatesize/ratio,coordinatesize/ratio,-coordinatesize,coordinatesize);
    else
        glOrtho(-coordinatesize*ratio,coordinatesize*ratio,-coordinatesize,coordinatesize,-coordinatesize,coordinatesize);
    //对模型视图矩阵堆栈应用随后的矩阵操作
    glMatrixMode(GL_MODELVIEW);
    //重置当前指定的矩阵为单位矩阵　
    glLoadIdentity();
}

//按键输入处理回调函数
void specialKey(int key,int x,int y){

    if(key==GLUT_KEY_UP){
        xRotAngle-=5.0f;
    }
    else if(key==GLUT_KEY_DOWN){
        xRotAngle+=5.0f;
    }
    else if(key==GLUT_KEY_LEFT){
        yRotAngle-=5.0f;
    }
    else if(key==GLUT_KEY_RIGHT){
        yRotAngle+=5.0f;
    }
    //重新绘制
    glutPostRedisplay();
}

int main(int argc, char* argv[])
{
    //初始化glut 
    glutInit(&argc,argv);
    //使用双缓冲区模式
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGBA|GLUT_DEPTH);
    //获取系统的宽像素
    SCREEN_WIDTH=glutGet(GLUT_SCREEN_WIDTH);
    //获取系统的高像素
    SCREEN_HEIGHT=glutGet(GLUT_SCREEN_HEIGHT);
	//创建窗口，窗口名字为OpenGL TriAngleFan Demo
    glutCreateWindow("OpenGL TriAngleFan Demo");
    //设置窗口大小
    glutReshapeWindow(windowWidth,windowHeight);
    //窗口居中显示
    glutPositionWindow((SCREEN_WIDTH-windowWidth)/2,(SCREEN_HEIGHT-windowHeight)/2);
    //窗口大小变化时的处理函数
    glutReshapeFunc(changSize);
    //设置显示回调函数 
    glutDisplayFunc(renderScreen);
    //设置按键输入处理回调函数
    glutSpecialFunc(specialKey);
    //设置全局渲染参数
    setupRederingState();
    glutMainLoop();
    return 0;
}