* Exam on Thursday...

* Triangles - ray tracing intersection with, rasterization



void cube() {
  // now draw the faces of the cube - four points for each face.
  glBegin(GL_QUADS);

  glColor3f(0.0f,1.0f,0.0f); // green
  glVertex3f( 1.0f, 1.0f,-5.0f);
  glVertex3f(-1.0f, 1.0f,-5.0f);
  glVertex3f(-1.0f, 1.0f, -4.0f);
  glVertex3f( 1.0f, 1.0f, -4.0f);

  glColor3f(1.0f,0.0f,0.0f); // red
  glVertex3f( 1.0f,-1.0f, -4.0f);
  glVertex3f(-1.0f,-1.0f, -4.0f);
  glVertex3f(-1.0f,-1.0f,-5.0f);
  glVertex3f( 1.0f,-1.0f,-5.0f);

  glColor3f(0.0f,0.0f,1.0f); // blue
  glVertex3f( 1.0f, 1.0f, -4.0f);
  glVertex3f(-1.0f, 1.0f, -4.0f);
  glVertex3f(-1.0f,-1.0f, -4.0f);
  glVertex3f( 1.0f,-1.0f, -4.0f);

  glColor3f(1.0f,1.0f,0.0f); 
  glVertex3f( 1.0f,-1.0f,-5.0f);
  glVertex3f(-1.0f,-1.0f,-5.0f);
  glVertex3f(-1.0f, 1.0f,-5.0f);
  glVertex3f( 1.0f, 1.0f,-5.0f);

  glColor3f(0.0f,1.0f,1.0f);
  glVertex3f(-1.0f, 1.0f, -4.0f);
  glVertex3f(-1.0f, 1.0f,-5.0f);
  glVertex3f(-1.0f,-1.0f,-5.0f);
  glVertex3f(-1.0f,-1.0f, -4.0f);

  glColor3f(1.0f,0.0f,1.0f);
  glVertex3f( 1.0f, 1.0f,-5.0f);
  glVertex3f( 1.0f, 1.0f, -4.0f);
  glVertex3f( 1.0f,-1.0f, -4.0f);
  glVertex3f( 1.0f,-1.0f,-5.0f);

  glEnd(); 
  
}


for (int i=0; i< 10; i++) {
  for (int j = 0; j < 10; j++) {
    glPushMatrix();
    glTranslatef(i, j, 0.0f);
    cube();
    glPopMatrix();
}}