OpenGL一个简单的纹理贴图

#define GLUT_DISABLE_ATEXIT_HACK 
#include <GL/glut.h>

#define    WIDTH 64
#define    HEIGHT 64
GLubyte Image[HEIGHT][WIDTH][4];
GLfloat xRot;


void makeImage(void)
{
    int i, j, c;
     
    for (i = 0; i < HEIGHT; i++) {
       for (j = 0; j < WIDTH; j++) {
          c = ((((i&0x8)==0)^((j&0x8))==0))*255;
          Image[i][j][0] = (GLubyte) c;
          Image[i][j][1] = (GLubyte) c;
          Image[i][j][2] = (GLubyte) c;
          Image[i][j][3] = (GLubyte) 255;
       }
    }
}
 
void init(void)
{
    glClearColor (0.0, 0.0, 0.0, 0.0);

 
    makeImage();
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);    //设置纹理参数
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, WIDTH, HEIGHT, 
                 0, GL_RGBA, GL_UNSIGNED_BYTE, Image);

    glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_DECAL);    //设置纹理环境
    glEnable(GL_TEXTURE_2D);                                //启用二维纹理

 }
 
 void display(void)
 {
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glEnable(GL_TEXTURE_2D);
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
 
    glPushMatrix();
    glColor4f(0,1,0,1);
    glTranslatef(0.0, 0.0,-6.0);
    glRotatef(xRot,1,0,0);
    glBegin(GL_QUADS);                                        //指定纹理坐标
    glTexCoord2f(0.0, 0.0); glVertex3f(-2.0, -2.0, 0.0);
    glTexCoord2f(0.0, 1.0); glVertex3f(-2.0, 2.0, 0.0);
    glTexCoord2f(1.0, 1.0); glVertex3f(2.0, 2.0, 0.0);
    glTexCoord2f(1.0, 0.0); glVertex3f(2.0, -2.0, 0.0);
    glEnd();

    glPopMatrix();
 
    glFlush();

 }
 
 void reshape(int w, int h)
 {
    glViewport(0, 0, (GLsizei) w, (GLsizei) h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0, 30.0);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

 }

 void OnTimer(int value)
 {
     xRot++;            //旋转角度增量
     glutPostRedisplay();
     glutTimerFunc(10,OnTimer,1);
 }

 void main(int argc, char** argv)
 {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(250, 250);
    glutInitWindowPosition(100, 100);
    glutCreateWindow(argv[0]);
    init();
    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutTimerFunc(10,OnTimer,1);
    glutMainLoop();
 }