opengl多重采样

效果图如下，两幅图效果是一样的，只是换了个背景。两幅图均是左侧使用了多重采样，右侧的没有使用多重采样。

 

#include <GL/glut.h>
#include <stdio.h>
static int bgtoggle = 1;

void init(void){
    GLint buf,sbuf;
    int i,j;
    glClearColor(0.0,0.0,0.0,0.0);
    glGetIntegerv(GL_SAMPLE_BUFFERS,&buf);
    printf("number of sample buffers is %d  \n",buf);
    glGetIntegerv(GL_SAMPLES,&sbuf);
    printf("number of samples is %d   \n",sbuf);

    glNewList(1,GL_COMPILE);
    for(i=0;i<19;++i ){
        glPushMatrix();
        glRotatef(360.0*(GLfloat)i/19.0,0.0,0.0,1.0);
        glColor3f(1.0,1.0,1.0);
        glLineWidth((i%3)+1.0);
        glBegin(GL_LINES);
            glVertex2f(0.3,0.0);
            glVertex2f(0.0,1.0);
//            glVertex2f(0.25,0.25);
//            glVertex2f(0.9,0.2);
       glEnd();
       glColor3f(0.0,1.0,1.0);
       glBegin(GL_TRIANGLES);
            glVertex2f(0.25,0.0);
            glVertex2f(0.9,0.0);
            glVertex2f(0.875,0.10);
       glEnd();
       glPopMatrix();
    }
    glEndList();

    glNewList(2,GL_COMPILE);
    glColor3f(1.0,0.5,0.0);
    glBegin(GL_QUADS);
        for(i=0;i<16;i++){
            for(j=0;j<16;j++){
                if(((i+j)%2)==0){
                    glVertex2f(-2.0+(i*0.25),-2.0+(j*0.25));
                    glVertex2f(-2.0+(i*0.25),-1.75+(j*0.25));
                    glVertex2f(-1.75+(i*0.25),-1.75+(j*0.25));
                    glVertex2f(-1.75+(i*0.25),-2.0+(j*0.25));
                }
            }
        }
    glEnd();
    glEndList();
}

void display(void){
    glClear(GL_COLOR_BUFFER_BIT);
    if(bgtoggle)
        glCallList(2);
    glEnable(GL_MULTISAMPLE);
    glPushMatrix();
    glTranslatef(-1.0,0.0,0.0);
    glCallList(1);
    glPopMatrix();

    glDisable(GL_MULTISAMPLE);
    glPushMatrix();
    glTranslatef(1.0,0.0,0.0);
    glCallList(1);
    glPopMatrix();
    glutSwapBuffers();
}

void keyboard(unsigned char key,int x,int y){
    switch(key){
    case 'b':
    case 'B':
        bgtoggle = ! bgtoggle;
        glutPostRedisplay();
        break;
    case 27:
        exit(0);
        break;
    }
}
void reshape(int w,int h){
    glViewport(0,0,(GLsizei)w,(GLsizei)h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    if(w<=h){
        gluOrtho2D(-1.0,1.0,-1.0*(GLfloat)h/(GLfloat)w,1.0*(GLfloat)h/(GLfloat)w);
    }else{
        gluOrtho2D(-1.0*(GLfloat)w/(GLfloat)h,1.0*(GLfloat)w/(GLfloat)h,-1.0,1.0);
    }
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
}

int main(int argc,char ** argv){
    glutInit(&argc,argv);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB|GLUT_MULTISAMPLE);
    glutInitWindowSize(400,400);
    glutCreateWindow(argv[0]);
    init();
    glutReshapeFunc(reshape);
    glutKeyboardFunc(keyboard);
    glutDisplayFunc(display);
    glutMainLoop();
    return 0;
}