#include <GL/openglut.h>
#include <stdlib.h>
#include <math.h>
GLfloat ctrlpoints[4][4][3] = {
    {{ -1.5, -1.5, 4.0}, { -0.5, -1.5, 2.0},
    {0.5, -1.5, -1.0}, {1.5, -1.5, 2.0}},
    {{ -1.5, -0.5, 1.0}, { -0.5, -0.5, 3.0},
    {0.5, -0.5, 0.0}, {1.5, -0.5, -1.0}},
    {{ -1.5, 0.5, 4.0}, { -0.5, 0.5, 0.0},
    {0.5, 0.5, 3.0}, {1.5, 0.5, 4.0}},
    {{ -1.5, 1.5, -2.0}, { -0.5, 1.5, -2.0},
    {0.5, 1.5, 0.0}, {1.5, 1.5, -1.0}}
};
GLfloat texpts[2][2][2] = {{{0.0, 0.0}, {0.0, 1.0}},
            {{1.0, 0.0}, {1.0, 1.0}}};
void display(void)
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glColor3f(1.0, 1.0, 1.0);
    glEvalMesh2(GL_FILL, 0, 20, 0, 20);
    glFlush();
}
#define imageWidth 64
#define imageHeight 64
GLubyte image[3*imageWidth*imageHeight];
void makeImage(void)
{
    int i, j;
    float ti, tj;
    for (i = 0; i < imageWidth; i++) {
    ti = 2.0*3.14159265*i/imageWidth;
    for (j = 0; j < imageHeight; j++) {
        tj = 2.0*3.14159265*j/imageHeight;
        image[3*(imageHeight*i+j)] = (GLubyte) 127*(1.0+sin(ti));
        image[3*(imageHeight*i+j)+1] = (GLubyte) 127*(1.0+cos(2*tj));
        image[3*(imageHeight*i+j)+2] = (GLubyte) 127*(1.0+cos(ti+tj));
    }
    }
}
void myinit(void)
{
    glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4,
        0, 1, 12, 4, &ctrlpoints[0][0][0]);
    glMap2f(GL_MAP2_TEXTURE_COORD_2, 0, 1, 2, 2,
        0, 1, 4, 2, &texpts[0][0][0]);
    glEnable(GL_MAP2_TEXTURE_COORD_2);
    glEnable(GL_MAP2_VERTEX_3);
    glMapGrid2f(20, 0.0, 1.0, 20, 0.0, 1.0);
    makeImage();
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    glTexImage2D(GL_TEXTURE_2D, 0, 3, imageWidth, imageHeight, 0,
         GL_RGB, GL_UNSIGNED_BYTE, image);
    glEnable(GL_TEXTURE_2D);
    glEnable(GL_DEPTH_TEST);
    glEnable(GL_NORMALIZE);
    glShadeModel (GL_FLAT);
}
void myReshape(int w, int h)
{
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    if (w <= h)
    glOrtho(-4.0, 4.0, -4.0*(GLfloat)h/(GLfloat)w,
        4.0*(GLfloat)h/(GLfloat)w, -4.0, 4.0);
    else
    glOrtho(-4.0*(GLfloat)w/(GLfloat)h,
        4.0*(GLfloat)w/(GLfloat)h, -4.0, 4.0, -4.0, 4.0);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glRotatef(85.0, 1.0, 1.0, 1.0);
}
static void
key(unsigned char k, int x, int y)
{
  switch (k) {
  case 27:  
    exit(0);
    break;
  default:
    return;
  }
  glutPostRedisplay();
}
int main(int argc, char** argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
    glutCreateWindow (argv[0]);
    myinit();
    glutReshapeFunc (myReshape);
    glutDisplayFunc(display);
    glutKeyboardFunc(key);
    glutMainLoop();
    return 0;             
}