xrot.java

用java3d做的一个粒子系统可以控制粒子运动

import javax.media.j3d.*;
import javax.vecmath.*;

import java.util.Enumeration;
import java.awt.event.*;

/*
  need to make sure you click to get focus.

 */

final class XRot extends TransformGroup {

    private Transform3D transform = new Transform3D();

    public XRot(){
	addChild(new Rotater(this));
    }

    final class Rotater extends Behavior {

	final WakeupCondition w = new WakeupOnAWTEvent(KeyEvent.KEY_PRESSED);

	public Rotater(TransformGroup tg){
	    tg.setCapability(tg.ALLOW_TRANSFORM_WRITE);
	}

	public void initialize(){
	    setSchedulingBounds(new BoundingSphere(new Point3d(),1000));
	    wakeupOn(w);
	}

	public void processStimulus(Enumeration criteria){
	    keyPress((KeyEvent)((WakeupOnAWTEvent)criteria.nextElement()).getAWTEvent()[0]);
            wakeupOn(w);
	}

	void keyPress(KeyEvent e){
	    int key = e.getKeyCode();

	    if(key==e.VK_UP){

		System.out.println("up");

		Transform3D t = new Transform3D();
		t.rotX(-Math.PI/180*5);

		transform.mul(t);
		setTransform(transform);
		
	    }
	    
	    else if(key==e.VK_DOWN){

		System.out.println("down");

		Transform3D t = new Transform3D();
		t.rotX(Math.PI/180*5);

		transform.mul(t);
		setTransform(transform);
	    }
	}

    }

}