/*
 * SimpleOpenGL.java
 *
 */

import com.sun.opengl.util.FPSAnimator;
import com.sun.opengl.util.GLUT;
import java.awt.BorderLayout;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.media.opengl.GL;
import javax.media.opengl.GLAutoDrawable;
import javax.media.opengl.GLCanvas;
import javax.media.opengl.GLEventListener;
import javax.media.opengl.glu.GLU;
import javax.swing.JFrame;

/**
 * This class illustrates a simple Java OpenGL program.
 * The openGL commands are rendered into a GLCanvas which
 * is displayed in a JFrame.  A glut teapot is displayed. 
 */
public class SimpleOpenGL implements GLEventListener {
    private GLU glu = new GLU();  // OpenGL Utility Library - used to set camera view
    private GLUT glut = new GLUT();  // OpenGL Utility Toolkit - contains teapot  
    
    /**
     * Create a SimpleOpenGL object.
     */
    public SimpleOpenGL() {
    }
    
    /**
     * Initializes parameters.
     * @param d  Object that provides support for OpenGL rendering.
     **/
    public void init( GLAutoDrawable d ) {
        GL gl = d.getGL();
        gl.glClearColor( .2f,.2f,.5f,0 );
        
        gl.glMatrixMode(GL.GL_PROJECTION);
        gl.glLoadIdentity();
        glu.gluPerspective(20.0f, 1.0f, 1.0f, 200.0f);
        gl.glMatrixMode(GL.GL_MODELVIEW);
        
        gl.glEnable(GL.GL_DEPTH_TEST);
    }
    
    /**
     * Called when the window is resized.
     * @param d  Object that provides support for OpenGL rendering.
     * @param x horizontal location of upper left corner of window.
     * @param y vertical location of upper left corner of window.
     * @param width width of window.
     * @param height height of window.
     **/
    public void reshape(GLAutoDrawable d, int x, int y, int width, int height ){
        GL gl = d.getGL();
        gl.glViewport(0,0, width, height);
        gl.glMatrixMode(GL.GL_PROJECTION);
        gl.glLoadIdentity();
        glu.gluPerspective(60.,(double)width/height, 1.0, 300.);
        gl.glMatrixMode(GL.GL_MODELVIEW);       
    }
    
     /**
     * Draws what is on the canvas.
     * @param d  Object that provides support for OpenGL rendering.
     **/
    public void display( GLAutoDrawable d ) {  
        GL gl = d.getGL();
        gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
        gl.glMatrixMode(GL.GL_MODELVIEW);
        gl.glLoadIdentity();     
        glu.gluLookAt(5.0, 2.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
        
        gl.glRotated(45,0,1,0);  // rotate by 45 degrees about y (up) axis
        glut.glutWireTeapot(1);      
    }
    
   
    

     /**
     * Starting point of execution.
     * @param args  command line arguments. Not used here.
     **/
    public static void main( String[] args ) {
		JFrame frame = new JFrame();
		frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
		
		// Create a GLCanvas object and place into the JFrame
		GLCanvas canvas = new GLCanvas();
		canvas.setSize(400,400);
		
		// Add an instance of SimpleOpenGL as the GLEventListener for
		// the GLCanvas.
                SimpleOpenGL listener = new SimpleOpenGL();
		canvas.addGLEventListener( listener );
		               
                // add the GLCanvas to the JFrame
		frame.getContentPane().add( canvas, BorderLayout.CENTER );
		
		frame.pack();
		frame.setVisible( true );
	}
    /**
     * Called by the drawable when the display mode or the display device associated 
     * with the GLAutoDrawable has changed. Not used here but must be included 
     * for interface.
     **/
    public void displayChanged( GLAutoDrawable d, boolean modeChanged,
            boolean deviceChanged ) { }
}