OpenGL入门笔记（十七）

#include <windows.h>
#include <GL/glut.h>
#include <math.h>
#include <stdlib.h>

void InitGL(GLvoid)
{
    glClearColor(1.0,1.0,1.0,1.0);

}

void triangle(void)
{
    glBegin(GL_TRIANGLES);
    glColor3f(1.0,1.0,0.0);
    glVertex2f(10.0,10.0);
    glColor3f(0.0,0.3,1.0);
    glVertex2f(20.0,30.0);
    glColor3f(1.0,0.0,0.0);
    glVertex2f(30.0,10.0);
    glEnd();
}

void DrawScene()
{
    int i;
    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
    glTranslatef(10.0,100.0,0.0);
    triangle();
    glPopMatrix();

    for(i = 0;i<5;i++)
    {
        glRasterPos2i(20+i*30,10+i*5);
        glCopyPixels(50,200,500,500,GL_COLOR);
    }
    glPopMatrix();
    glFlush();

}

void ReShape(int w,int h)
{
    glViewport(0,0,(GLsizei)w,(GLsizei)h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    if(w<=h)
        gluOrtho2D(0.0,150,0.0,150.0*(GLfloat)h/(GLfloat)w);
    else
        gluOrtho2D(0.0,150.0*(GLfloat)w/(GLfloat)h,0.0,150.0);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

}
int main(int argc,char** argv)
{
    glutInit(&argc,argv);
    glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB|GLUT_DEPTH);
    glutInitWindowSize(500,400);
    glutInitWindowPosition(100,100);
    glutCreateWindow("OpenGL");
    InitGL();
    glutReshapeFunc(ReShape);
    glutDisplayFunc(DrawScene);
    glutMainLoop();
    return 0;
}