/* Copyright (c) Mark J. Kilgard, 1997. */

/* This program is freely distributable without licensing fees 
   and is provided without guarantee or warrantee expressed or 
   implied. This program is -not- in the public domain. */

/* This program was requested by Patrick Earl; hopefully someone else
   will write the equivalent Direct3D immediate mode program. */

#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <GL/glut.h>

GLfloat light_diffuse[] = {1.0, 0.0, 0.0, 1.0};  /* Red diffuse light. */
GLfloat light_position[] = {1.0, 1.0, 1.0, 0.0};  /* Infinite light location. */

void
stroke_output(GLfloat Scale, GLfloat x, GLfloat y, GLfloat z, char *format,...)
{
  va_list args;
  char buffer[200], *p;

  va_start(args, format);
  vsprintf(buffer, format, args);
  va_end(args);
  glPushMatrix();
  glTranslatef(x, y, z);
  glScalef(0.005*Scale, 0.005*Scale, 0.005*Scale);
  for (p = buffer; *p; p++)
    glutStrokeCharacter(GLUT_STROKE_ROMAN, *p);
  glPopMatrix();
}


void
drawAxes(void) 
{

  glDisable(GL_LIGHTING);
   glBegin(GL_LINES);
   glColor3f(1.0, 1.0, 1.0);
   glVertex3f(-2.0, 0.0, 0.0);
   glVertex3f( 2.0, 0.0, 0.0);
   glVertex3f( 0.0, -2.0, 0.0);
   glVertex3f( 0.0,  2.0, 0.0);
   glVertex3f( 0.0, 0.0, -2.0);
   glVertex3f( 0.0, 0.0, 2.0);
   glEnd();
   
   stroke_output(0.5, 2.0, 0.0, 0.0, "X");
   stroke_output(0.5, 0.0, 2.0, 0.0, "Y");
   stroke_output(0.5, 0.0, 0.0, 2.0, "Z");
}

void
drawBox(void)
{

  glEnable(GL_LIGHTING);
    glBegin(GL_QUADS);
    glNormal3f(0.0,0.0,-1.0); /*Front side 1 2 3 4*/
    glVertex3f( 1.0,  1.0,  1.0); glVertex3f( 1.0, -1.0,  1.0);
    glVertex3f(-1.0, -1.0,  1.0); glVertex3f(-1.0,  1.0,  1.0);
    glNormal3f(-1.0, 0.0, 0.0); /*Left side 4 5 6 3*/
    glVertex3f(-1.0,  1.0,  1.0); glVertex3f(-1.0, 1.0, -1.0);
    glVertex3f(-1.0, -1.0, -1.0); glVertex3f(-1.0,-1.0,  1.0);  
    glNormal3f(1.0, 0.0, 0.0); /*Right side 8 1 2 7*/
    glVertex3f( 1.0,  1.0, -1.0); glVertex3f( 1.0,  1.0,  1.0);
    glVertex3f( 1.0, -1.0,  1.0); glVertex3f( 1.0, -1.0, -1.0);
    glNormal3f(0.0, 0.0, -1.0); /*Back side 5 6 7 8*/
    glVertex3f(-1.0,  1.0, -1.0); glVertex3f(-1.0, -1.0, -1.0);
    glVertex3f( 1.0, -1.0, -1.0); glVertex3f( 1.0,  1.0, -1.0);
    glNormal3f(0.0, 1.0, 0.0); /*Top side 8 5 4 1*/
    glVertex3f( 1.0,  1.0, -1.0); glVertex3f(-1.0,  1.0, -1.0);
    glVertex3f(-1.0,  1.0,  1.0); glVertex3f( 1.0,  1.0,  1.0);
    glNormal3f(0.0, -1.0, 0.0); /*Bottom side 2 3 6 7*/
    glVertex3f( 1.0, -1.0,  1.0); glVertex3f(-1.0, -1.0,  1.0);
    glVertex3f(-1.0, -1.0, -1.0); glVertex3f( 1.0, -1.0, -1.0);;
    glEnd();

}

void
display(void)
{
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  drawAxes();
  drawBox();
  glutSwapBuffers();
}

void
init(void)
{

  /* Enable a single OpenGL light. */
  glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
  glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  glEnable(GL_LIGHT0);
  glEnable(GL_LIGHTING);

  /* Use depth buffering for hidden surface elimination. */
  glEnable(GL_DEPTH_TEST);

  /* Setup the _view of the cube. */
  glMatrixMode(GL_PROJECTION);
  gluPerspective( /* field of view in degree */ 40.0,
    /* aspect ratio */ 1.0,
    /* Z near */ 1.0, /* Z far */ 10.0);
  glMatrixMode(GL_MODELVIEW);
  gluLookAt(0.0, 0.0, 5.0,  /* eye is at (0,0,5) */
    0.0, 0.0, 0.0,      /* center is at (0,0,0) */
    0.0, 1.0, 0.);      /* up is in positi_ve Y direction */

  /* Adjust cube position to be asthetic angle. */
  glTranslatef(0.0, 0.0, -1.0);
  glRotatef(60, 1.0, 0.0, 0.0);
  glRotatef(-20, 0.0, 0.0, 1.0);
}

int
main(int argc, char **argv)
{
  glutInit(&argc, argv);
  glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
  glutCreateWindow("red 3D lighted cube");
  glutDisplayFunc(display);
  init();
  glutMainLoop();
  return 0;             /* ANSI C requires main to return int. */
}