import java.applet.Applet;
import java.awt.Graphics;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;

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

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

    private static final float ctrlpoints [][][] = {
    			{{-1.5f, -1.5f,  4.0f},
			 {-0.5f, -1.5f,  2.0f},
			 { 0.5f, -1.5f, -1.0f},
			 { 1.5f, -1.5f,  2.0f}},
    			{{-1.5f, -0.5f,  1.0f},
			 {-0.5f, -0.5f,  3.0f},
			 { 0.5f, -0.5f,  0.0f},
			 { 1.5f, -0.5f, -1.0f}},
    			{{-1.5f,  0.5f,  4.0f},
			 {-0.5f,  0.5f,  0.0f},
			 { 0.5f,  0.5f,  3.0f},
			 { 1.5f,  0.5f,  4.0f}},
    			{{-1.5f,  1.5f, -2.0f},
			 {-0.5f,  1.5f, -2.0f},
			 { 0.5f,  1.5f,  0.0f},
			 { 1.5f,  1.5f, -1.0f}}};

    private void initlights () {
	float ambient[] = {0.2f, 0.2f, 0.2f, 1.0f};
	float position[] = {0.0f, 0.0f, 2.0f, 1.0f};
	float mat_diffuse[] = {0.6f, 0.6f, 0.6f, 1.0f};
	float mat_specular[] = {1.0f, 1.0f, 1.0f, 1.0f};
        float mat_shininess[] = {50.0f};

        myGL.glEnable (GL.GL_LIGHTING);
        myGL.glEnable (GL.GL_LIGHT0);
        myGL.glLightfv (GL.GL_LIGHT0, GL.GL_AMBIENT, ambient);
        myGL.glLightfv (GL.GL_LIGHT0, GL.GL_POSITION, position);

        myGL.glMaterialfv (GL.GL_FRONT, GL.GL_DIFFUSE, mat_diffuse);
        myGL.glMaterialfv (GL.GL_FRONT, GL.GL_SPECULAR, mat_specular);
        myGL.glMaterialfv (GL.GL_FRONT, GL.GL_SHININESS, mat_shininess);
    }

    private void myinit () {
	myGL.glClearColor (0.0f, 0.0f, 0.0f, 1.0f);
	myGL.glMap2f (GL.GL_MAP2_VERTEX_3, 0.0f, 1.0f, 3, 4,
		      0.0f, 1.0f, 12, 4, ctrlpoints);
	myGL.glEnable (GL.GL_MAP2_VERTEX_3);
	myGL.glEnable (GL.GL_AUTO_NORMAL);
	myGL.glEnable (GL.GL_NORMALIZE);
	myGL.glMapGrid2f (20, 0.0f, 1.0f, 20, 0.0f, 1.0f);
	initlights ();		/* for lighted version only */
    }

    private void display () {
	myGL.glClear (GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
	myGL.glPushMatrix ();
	myGL.glRotatef (85.0f, 1.0f, 1.0f, 1.0f);
	myGL.glEvalMesh2 (GL.GL_FILL, 0, 20, 0, 20);
	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 ();
	if (w <= h) {
	    myGL.glOrtho (-4.0f, 4.0f,
	    		  -4.0f *(float)h/(float)w,
			   4.0f *(float)h/(float)w,
			  -4.0f, 4.0f);
	} else {
	    myGL.glOrtho (-4.0f *(float)w/(float)h,
	    		   4.0f *(float)w/(float)h,
			  -4.0f, 4.0f,
			  -4.0f, 4.0f);
	}
        myGL.glMatrixMode (GL.GL_MODELVIEW);
        myGL.glLoadIdentity ();
    }

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

    public void paint (Graphics g) {
    	// STRANGE if call display here, it will be never stoped
	myGL.glXSwapBuffers (g, this);
    }

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

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

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

}