/** 
 * Show effects of different orders of rotation. 
 * pressing x rotates about x axis, y about y, z about z, r resets things
 */

import java.awt.*;
import java.awt.event.*; 
import javax.media.opengl.*;
import javax.media.opengl.glu.*;
import com.sun.opengl.util.*;

public class Toy3 extends Frame 
    implements GLEventListener, KeyListener
{


    GLCanvas glc = null;
    int aWidth = 400;
    int aHeight = 400;
    float[] identity  = {1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1};
    float[] currentRotation;
    char lastKey;

    public static void main(String[] args){
	Toy3 t = new Toy3();
    }

    public Toy3(){
        super("Toy3");

	glc = new GLCanvas();

        add("Center", glc);
	

        glc.addGLEventListener(this);
        glc.addKeyListener(this);
        currentRotation = (float []) identity.clone();
        setSize(aWidth,aHeight);
	setVisible(true);
    }


    
    public void init(GLAutoDrawable drawable){
	GL gl = drawable.getGL();
        gl.glClearColor(0.2f, 0.3f, 0.2f, 1.0f);
    }

   public void keyTyped(KeyEvent evt){
	if ( evt.getKeyChar() == 'q' || evt.getKeyChar() == 'Q' ) {
	    dispose();
	}
	
        lastKey = evt.getKeyChar(); //save the key typed
	glc.repaint();
	return;
   }
    


    public void keyReleased(KeyEvent evt){

    }

    public void keyPressed(KeyEvent evt){
    }
    
    public void reshape(GLAutoDrawable drawable, int x, int y, int width, int height){
	GL gl = drawable.getGL();
        gl.glViewport(0, 0, width, height);
        gl.glMatrixMode(GL.GL_PROJECTION);
        gl.glLoadIdentity();
        gl.glOrtho(-2, 2, -2, 2, -5, 10);
        gl.glMatrixMode(GL.GL_MODELVIEW);
        gl.glLoadIdentity();
        gl.glEnable(GL.GL_DEPTH_TEST);
    }

    public void rotate(GL gl, float[] currentRotation, int angle, int x, int y, int z){
        gl.glPushMatrix();
        gl.glLoadIdentity();
        gl.glRotatef(angle, x, y, z);
        gl.glMultMatrixf(currentRotation, 0); //multiply rotation matrices together
        gl.glGetFloatv(GL.GL_MODELVIEW_MATRIX, currentRotation, 0); //save result
        gl.glPopMatrix();
    }

    void doRotate(GL gl) {
	if ( lastKey == 'x' || lastKey == 'X' ) { 
	    rotate(gl, currentRotation, 10, 1, 0, 0);
	}
	if ( lastKey == 'y' || lastKey == 'Y' ) { 
	    rotate(gl, currentRotation, 10, 0, 1, 0);
	}
	if ( lastKey == 'z' || lastKey == 'Z' ) { 
	    rotate(gl, currentRotation, 10, 0, 0, 1);
	}
	if ( lastKey == 'r' || lastKey == 'R' ) {
	    //reset currentRotation to be identity
	    currentRotation = (float []) identity.clone();
	}
        lastKey = 0;
    }

    public void display(GLAutoDrawable drawable){
	
        float[] teapotMat = {0.2f, 0.2f, 0.9f, 1.0f};
        float[] lightpos = {0f, 0.0f, 4.0f, 1.0f};
	GL gl = drawable.getGL();
        gl.glShadeModel(GL.GL_SMOOTH);
        gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
        gl.glLightfv(GL.GL_LIGHT0, GL.GL_POSITION, lightpos, 0);
        gl.glEnable(GL.GL_LIGHTING);
        gl.glEnable(GL.GL_LIGHT0);
        gl.glMaterialfv(GL.GL_FRONT_AND_BACK, GL.GL_AMBIENT_AND_DIFFUSE, teapotMat, 0);
	doRotate(gl);
        gl.glPushMatrix();
	gl.glMultMatrixf(currentRotation, 0);

	GLUT glut = new GLUT();
	glut.glutSolidTeapot(1);

        gl.glPopMatrix();

    }

    /** This method handles things if display depth changes */
    public void displayChanged(GLAutoDrawable drawable,
			       boolean modeChanged,
			       boolean deviceChanged){
    }
}