import java.applet.Applet;
import java.awt.Graphics;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.event.InputEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

// must import jgl.GL....
import jgl.GL;
import jgl.GLU;
import jgl.GLAUX;

public class movelight extends Applet
		       implements ComponentListener, MouseListener {
    // must use GL to use jGL.....
    // and use GLU to use the glu functions....
    // remember to give GL to initialize GLU
    // and use GLAUX to use the aux functions.....
    // remember to give GL to initialize GLAUX
    GL myGL = new GL ();
    GLU myGLU = new GLU (myGL);
    GLAUX myAUX = new GLAUX (myGL);

    private int spin = 0;

    private void movelight () {
    	spin = (spin + 30) % 360;
    }

    public void mouseClicked(MouseEvent e) {}
    public void mouseEntered(MouseEvent e) {}
    public void mouseExited(MouseEvent e) {}
    public void mouseReleased(MouseEvent e) {}

    public void mousePressed(MouseEvent e) {
        // process which button by myself
        if ((e.getModifiers() & InputEvent.BUTTON1_MASK)
            == InputEvent.BUTTON1_MASK) { // left
	    movelight ();
	    display ();
	    repaint ();
	    e.consume ();
        }
    } 

    private void myinit () {
	myGL.glEnable (GL.GL_LIGHTING);
	myGL.glEnable (GL.GL_LIGHT0);

	myGL.glDepthFunc (GL.GL_LESS);
	myGL.glEnable (GL.GL_DEPTH_TEST);
    }

    private void display () {
    	float position [] = {0.0f, 0.0f, 1.5f, 1.0f};

	myGL.glClear (GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
	myGL.glPushMatrix ();
	    myGL.glTranslatef (0.0f, 0.0f, -5.0f);

	    myGL.glPushMatrix ();
	    	myGL.glRotated ((double)spin, 1.0, 0.0, 0.0);
		myGL.glRotated (0.0, 1.0, 0.0, 0.0);
		myGL.glLightfv (GL.GL_LIGHT0, GL.GL_POSITION, position);

		myGL.glTranslated (0.0, 0.0, 1.5);
		myGL.glDisable (GL.GL_LIGHTING);
		myGL.glColor3f (0.0f, 1.0f, 1.0f);
		myAUX.auxWireCube (0.1);
		myGL.glEnable (GL.GL_LIGHTING);
	    myGL.glPopMatrix ();

	    myAUX.auxSolidTorus (0.275, 0.85);
	myGL.glPopMatrix ();
	myGL.glFlush ();
    }

    public void componentMoved (ComponentEvent e) {}
    public void componentShown (ComponentEvent e) {}
    public void componentHidden (ComponentEvent e) {}

    public void componentResized (ComponentEvent e) {
        // get window width and height by myself
	myReshape (getSize ().width, getSize ().height);
	display ();
	repaint ();
    }

    private void myReshape (int w, int h) {
        myGL.glViewport (0, 0, w, h);
        myGL.glMatrixMode (GL.GL_PROJECTION);
        myGL.glLoadIdentity ();
	myGLU.gluPerspective (40.0, (float)w/(float)h, 1.0, 20.0);
        myGL.glMatrixMode (GL.GL_MODELVIEW);
    }

    public void update (Graphics g) {
        // skip the clear screen command....
        paint (g);
    }

    public void paint (Graphics g) {
	myGL.glXSwapBuffers (g, this);
    }

    public void init () {
	myAUX.auxInitPosition (0, 0, 500, 500);
	myAUX.auxInitWindow (this);
	myinit ();

        // as call auxMouseFunc()
        addMouseListener(this);

	// as call auxReshapeFunc()
        addComponentListener (this);
	myReshape (getSize ().width, getSize ().height);

        // call display as call auxIdleFunc(display)
        display ();
    }

}