VS2012下基于Glut OpenGL绘制点(添加设置点大小)示例程序：

在VS2012下使用glut绘制一些列点(点大小顺序变大)的示例程序，绘制的是四个螺纹，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螺纹：

未进行平滑处理的效果：

进行了平滑处理的效果：

源代码如下所示：

// GlutPointszDemo.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//受支持的点大小范围GLfloat sizes[2];//受支持的点大小增量GLfloat step;void renderScreen(void){GLfloat x,y,z,angle;//当前点的大小GLfloat curSize=0.0f;//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状态如栈glPushMatrix();//坐标系绕x轴旋转xRotAngleglRotatef(xRotAngle,1.0f,0.0f,0.0f);//坐标系绕y轴旋转yRotAngleglRotatef(yRotAngle,0.0f,1.0f,0.0f);//当前点的大小curSize = sizes[0];z=-50.0f;//绘制四个螺纹for(angle=0.0f;angle<=((2.0f*GL_PI)*4.0f);angle+=0.1f){x=50.0f*cos(angle);y=50.0f*sin(angle);//设置点的大小glPointSize(curSize);//进行平滑处理　glEnable(GL_POINT_SMOOTH);glHint(GL_POINT_SMOOTH,GL_NICEST);//开始绘点glBegin(GL_POINTS);glVertex3f(x,y,z);//结束绘点glEnd();z+=0.4f;//点变大curSize+=step;}//恢复压入栈的MatrixglPopMatrix();//交换两个缓冲区的指针glutSwapBuffers();}//设置Redering State void setupRederingState(void){//设置清理颜色为白色glClearColor(0.0f,0.0,0.0,1.0f);//设置绘画颜色为红色glColor3f(0.0f,1.0f,0.0f);//获取受支持的点大小范围glGetFloatv(GL_POINT_SIZE_RANGE,sizes);//获取受支持的点大小增量glGetFloatv(GL_POINT_SIZE_GRANULARITY,&step);printf("point size range:%f-%f\n",sizes[0],sizes[1]);printf("point step:%f\n",step);}//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);elseglOrtho(-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();}//按键输入处理函数void sPecialkeyFuc(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[]){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PointsDemoglutCreateWindow("PointsDemo");//设置窗口大小glutReshapeWindow(windowWidth,windowHeight);//窗口居中显示glutPositionWindow((SCREEN_WIDTH-windowWidth)/2,(SCREEN_HEIGHT-windowHeight)/2);//设置窗口大小变化时的回调函数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(sPecialkeyFuc);//设置全局渲染参数setupRederingState();glutMainLoop();return 0;}