3D立体显示

　　由于右眼和左眼观看显示器的角度不同，利用这一角度差遮住光线就可将图像分配给右眼或者左眼，经过大脑将这两幅由差别的图像合成为一副具有空间深度和维度信息的图像，从而可以看到3D图像。

#include "GL/glut.h"
#include "stdlib.h"
#include "stdio.h"
#include "math.h"

static int big = 0;
static bool isLeftEye = false;

#define PI 3.1415926
const GLfloat R = 8.0;

static GLfloat leftMatrix[16] = {1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0,  0.0,
0.0, 0.0, 0.0, 1.0};

static GLfloat rightMatrix[16] = {1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0, 0.0,
0.0, 0.0, 0.0, 1.0};

static GLfloat leftPersMatrix[16] = {1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0, 0.0,
0.0, 0.0, 0.0, 1.0};

static GLfloat rightPersMatrix[16] = {1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0, 0.0,
0.0, 0.0, 0.0, 1.0};
void init(void)
{    
    const GLfloat SD = 0.06;
    GLfloat n = SD*R/2.0;
    //要是转秩
    //n=0;
    leftMatrix[12] = n;
    rightMatrix[12] = -n;

    //这里假设眼到屏幕为一米，以米为单位
    GLfloat p = SD/(2*1*tan(PI/6)*1);
    //p = 0.0;
    leftPersMatrix[12] = -p;
    rightPersMatrix[12] = p;

    GLfloat mat_specular[] = {0.8, 0.8, 0.0, 1.0};
    GLfloat mat_shininess[] = {50.0};
    GLfloat light_position[] = {1.0, 1.0, 1.0, 0.0};
    GLfloat white_light[] = {1.0, 1.0, 1.0, 1.0};
    GLfloat yellow_light[] = {1.0, 1.0, 0.0, 1.0};
    GLfloat lmodel_ambient[] = {0.0, 0.7, 0.5, 1.0};
    glClearColor(1.0, 1.0, 1.0, 0.0);

    glShadeModel(GL_SMOOTH);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
    glLightfv(GL_LIGHT0, GL_POSITION, light_position);
    glLightfv(GL_LIGHT0, GL_DIFFUSE, yellow_light);//主体的颜色
    glLightfv(GL_LIGHT0, GL_SPECULAR, white_light);//高光的颜色
    glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);

    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);
    glEnable(GL_DEPTH_TEST);
}

void display(void)
{
    glColorMask(1.0, 1.0,1.0,1.0);
    glClearColor(0.0,0.0,0.0,1.0);
    glClearDepth(1.0);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glColor3f(1.0, 1.0, 1.0);


    // 画左眼
    glMatrixMode(GL_PROJECTION);
    glPushMatrix();
    float mat[16];
    glGetFloatv(GL_PROJECTION_MATRIX,mat);
    glLoadIdentity();

    glMultMatrixf(leftPersMatrix);
    glMultMatrixf(mat);

    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glGetFloatv(GL_MODELVIEW_MATRIX,mat);
    glLoadIdentity();

    glMultMatrixf(leftMatrix);
    glMultMatrixf(mat);

    glColorMask(1.0, 0.0,0.0,1.0);

    glRotatef((GLfloat) big, 0.0, 1.0, 0.0);
    glutSolidTeapot(2.0);
    glPopMatrix();

    glMatrixMode(GL_PROJECTION);
    glPopMatrix();

    glFlush();

    //画右眼
    glClearDepth(1.0);
    glClear(GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_PROJECTION);
    glPushMatrix();
    glGetFloatv(GL_PROJECTION_MATRIX,mat);
    glLoadIdentity();

    glMultMatrixf(rightPersMatrix);
    glMultMatrixf(mat);

    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glGetFloatv(GL_MODELVIEW_MATRIX,mat);
    glLoadIdentity();

    glMultMatrixf(rightMatrix);
    glMultMatrixf(mat);
    glColorMask(0.0, 1.0,1.0,1.0);
    glRotatef((GLfloat) big, 0.0, 1.0, 0.0);
    glutSolidTeapot(2.0);
    glPopMatrix();

    glMatrixMode(GL_PROJECTION);
    glPopMatrix();
    glFlush();
    //glPopMatrix();
    //if(isLeftEye)
    //{    
    //    glMatrixMode(GL_PROJECTION);
    //    glMultMatrixf(leftPersMatrix);

    //    glMatrixMode(GL_MODELVIEW);
    //    glMultMatrixf(leftMatrix);
    //    glColorMask(1.0, 0.0,0.0,1.0);
    //    
    //    
    //    
    //    isLeftEye = false;
    //}else
    //{    
    //    
    //    glMatrixMode(GL_PROJECTION);
    //    glMultMatrixf(rightPersMatrix);

    //    glMatrixMode(GL_MODELVIEW);
    //    glMultMatrixf(rightMatrix);
    //    glColorMask(0.0, 1.0,1.0,1.0);    
    //    isLeftEye = true;
    //}

    //glRotatef((GLfloat) big, 0.0, 1.0, 0.0);
    //glutSolidTeapot(1.0);

    //glRotatef((GLfloat) big, 0.0, 1.0, 0.0);
    //glTranslatef(3.0, 0.0, 0.0);
    //glutSolidTeapot(0.5);

    glutSwapBuffers();


}
void reshape(int w, int h)
{
    glViewport(0, 0, (GLsizei) w, (GLsizei) h);

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(60, (GLfloat)w/(GLfloat)h, 0.01, 20.0);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    gluLookAt(0.0, 0.0, R, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0 );
}
void keyboard(unsigned char key, int x, int y)
{
    switch (key)
    {
    case 'b':
        big = (big + 1) % 360;
        glutPostRedisplay();
        break;
    case 'B':
        big = (big - 1) % 360;
        glutPostRedisplay();
        break;
    case 27:                // 按ESC键时退出程序
        exit (0);
        break;
    default:
        break;
    }
}
void spinDisplay(void)
{
    big = (big + 1) % 360;
    glutPostRedisplay();
}
int main (int argc, char** argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(500, 500);
    glutInitWindowPosition(100, 100);
    glutCreateWindow(argv[0]);
    init();
    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutKeyboardFunc(keyboard);
    glutIdleFunc(spinDisplay);
    glutMainLoop();

    return 0;
}

最终效果图如下：