A. Remaining C code

GLfloat vertices[][3] = {{-1.0,-1.0,-1.0},{1.0,-1.0,-1.0},
{1.0,1.0,-1.0}, {-1.0,1.0,-1.0}, {-1.0,-1.0,1.0}, 
{1.0,-1.0,1.0}, {1.0,1.0,1.0}, {-1.0,1.0,1.0}};

GLfloat normals[][3] = {{-1.0,-1.0,-1.0},{1.0,-1.0,-1.0},
{1.0,1.0,-1.0}, {-1.0,1.0,-1.0}, {-1.0,-1.0,1.0}, 
{1.0,-1.0,1.0}, {1.0,1.0,1.0}, {-1.0,1.0,1.0}};

GLfloat colors[][3] = {{0.0,0.0,0.0},{1.0,0.0,0.0},
{1.0,1.0,0.0}, {0.0,1.0,0.0}, {0.0,0.0,1.0}, 
{1.0,0.0,1.0}, {1.0,1.0,1.0}, {0.0,1.0,1.0}};

void polygon(int a, int b, int c , int d)
{
/* draw a polygon via list of vertices */
glBegin(GL_POLYGON);
glColor3fv(colors[a]);
glNormal3fv(normals[a]);
glVertex3fv(vertices[a]);
glColor3fv(colors[b]);
glNormal3fv(normals[b]);
glVertex3fv(vertices[b]);
glColor3fv(colors[c]);
glNormal3fv(normals[c]);
glVertex3fv(vertices[c]);
glColor3fv(colors[d]);
glNormal3fv(normals[d]);
glVertex3fv(vertices[d]);
glEnd();
}

void colorcube(void)
{
/* map vertices to faces */
polygon(0,3,2,1);
polygon(2,3,7,6);
polygon(0,4,7,3);
polygon(1,2,6,5);
polygon(4,5,6,7);
polygon(0,1,5,4);
}

static GLfloat theta[] = {0.0,0.0,0.0};
static GLint axis = 2;

void spinCube()
{
/* Idle callback, spin cube 2 degrees about selected axis */
   theta[axis] += 2.0;
   if( theta[axis] > 360.0 ) theta[axis] -= 360.0;
   display();
}

void mouse(int btn, int state, int x, int y)
{
/* mouse callback, selects an axis about which to rotate */
   if(btn==GLUT_LEFT_BUTTON & state == GLUT_DOWN) axis = 0;
   if(btn==GLUT_MIDDLE_BUTTON & state == GLUT_DOWN) axis = 1;
   if(btn==GLUT_RIGHT_BUTTON & state == GLUT_DOWN) axis = 2;
}

void myReshape(int w, int h)
{
   glViewport(0, 0, w, h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   if (w <= h)
     glOrtho(-2.0, 2.0, -2.0 * (GLfloat) h / (GLfloat) w,
      2.0 * (GLfloat) h / (GLfloat) w, -10.0, 10.0);
   else
     glOrtho(-2.0 * (GLfloat) w / (GLfloat) h,
      2.0 * (GLfloat) w / (GLfloat) h, -2.0, 2.0, -10.0, 10.0);
   glMatrixMode(GL_MODELVIEW);
}