石正坤一、实验目的：1.了解OpenGL下简单图形的平移、旋转、缩放变换的编程的基本思想；2.掌握OpenGL下简单图形的平移、旋转、缩放变换的编程的基本步骤；二、实验原理：在OpenGL中，可以使用下面三个函数便捷地实现简单图形平移、旋转、缩放变换的功能：glRotatef(theta,vx,vy,vz);glTranslatef(dx,dy,dz);glScalef(sx，sy，sz);三、实验内容：//1.cpp:Definestheentrypointfortheconsoleapplication.//#include"stdafx.h"#include"glut.h"#include"math.h"voiddisplay(){glClear(GL_COLOR_BUFFER_BIT);//CleartheframebufferglColor3f(0.0,1.0,1.0);//SetcurrentcolortogreenglBegin(GL_POLYGON);//DrawthetriangleglVertex2f(0.0,-0.2);glVertex2f(0.2,0.0);glVertex2f(0.0,0.0);glEnd();glFlush();}voiddsp(){glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);//CleartheframebufferglColor3f(0.0,1.0,1.0);//Setcurrentcolortogreendisplay();//--------------------------//平移glPushMatrix();glTranslatef(0.5,0.5,0.0);display();glPopMatrix();//--------------------------//缩放glPushMatrix();glScalef(0.5,0.5,0.0);display();glPopMatrix();//--------------------------//旋转glPushMatrix();glRotatef(60,0.0,0.0,1.0);display();glPopMatrix();}voidinit(){glClearColor(0.0,0.0,0.0,0.0);//Settheclearcolortoblack//SpecifytheboundariesoftheviewingwindowglMatrixMode(GL_PROJECTION);glLoadIdentity();gluOrtho2D(-1.0,1.0,-1.0,1.0);//Theparaare:(left,right,bottom,top)glMatrixMode(GL_MODELVIEW);}intmain(intargc,char*argv[]){glutInit(&argc,argv);glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH);glEnable(GL_DEPTH_TEST);glutCreateWindow("simple");glutDisplayFunc(dsp);init();glutMainLoop();return0;}原图：平移：缩放：旋转：四、实验总结：1.在分别查看图像的平移、缩放、旋转中的其中一个功能时，需要将其他两个的代码注释掉，否则只会显示旋转一个功能。2.当使用函数glScalef(sx,sy,sz)对图形作缩放操作时，若sy为正值，则图形保持正立；而当sy为负值时，则图形就变成倒立像。
