/* bteapot.c  Outlined teapot using Bezier surfaces */
/* E. Angel, Interactive Computer Graphics          */

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

typedef GLfloat point[3];
point data[32][4][4];

/* 306 vertices */
#include "vertices.h"

/* 32 patches each defined by 16 vertices, arranged in a 4 x 4 array */
/* NOTE: numbering scheme for teapot has vertices labeled from 1 to 306 */
/* remnent of the days of FORTRAN */

#include "patches.h"

void display(void)
{
  int i, j, k;

  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  glColor3f(1.0, 1.0, 1.0);
  glLoadIdentity();
  glTranslatef(0.0, 0.0, -10.0); 
  glRotatef(-35.26, 1.0, 0.0, 0.0);
  glRotatef(-45.0, 0.0, 1.0, 0.0);  

  /* gluLookAt(-1.0, 1.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0); */
  /* data aligned along z axis, rotate to align with y axis */

  glRotatef(-90.0, 1.0,0.0, 0.0); 
  for(k=0;k<32;k++) 
  {
    glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4,
           0, 1, 12, 4, &data[k][0][0][0]);
    for (j = 0; j <= 8; j++) 
    {
      glBegin(GL_LINE_STRIP);
      for (i = 0; i <= 30; i++)
      {
        glEvalCoord2f((GLfloat)i/30.0, (GLfloat)j/8.0);
      }
      glEnd();
      glBegin(GL_LINE_STRIP);
      for (i = 0; i <= 30; i++)
      {
        glEvalCoord2f((GLfloat)j/8.0, (GLfloat)i/30.0);
      }
      glEnd();
    }
  }
  glFlush();
}

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, -20.0, 20.0);
  else
     glOrtho(-4.0 * (GLfloat) w / (GLfloat) h,
            4.0 * (GLfloat) w / (GLfloat) h, -4.0, 4.0, -20.0, 20.0);
  glMatrixMode(GL_MODELVIEW);
  display();
}

void myinit()
{
  glEnable(GL_MAP2_VERTEX_3);
  glMapGrid2f(20, 0.0, 1.0, 20, 0.0, 1.0);
  glEnable(GL_DEPTH_TEST);
}

int main(int argc, char *argv[])
{
  int i,j, k, m, n;

  for(i=0;i<32;i++)
    for(j=0;j<4;j++)
      for(k=0;k<4;k++)
        for(n=0;n<3;n++)
        {
          /* put teapot data into single array for subdivision */

          m=indices[i][j][k];
          for(n=0;n<3;n++) data[i][j][k][n]=vertices[m-1][n];
        }
  glutInit(&argc, argv);
  glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
  glutInitWindowSize(500, 500);
  glutCreateWindow("teapot");
  myinit();
  glutReshapeFunc(myReshape);
  glutDisplayFunc(display);
  glutMainLoop();
  return 0;
}