/*   アニメーション実験  Ver 0.10   */
/*                                  */
/*                                  */
/*   by Atsushi         2005/8/20   */


package animation.animator;

import java.awt.*;
import java.awt.image.*;


public class WaveAnimator extends Object
{
	/*   ---   Field   ---   */

	private Image baseImage;
	private MemoryImageSource imageSource;

	private int waveLength,amplitude;
	private double phase;

	private int pixels[];
	private int basePixels[];
	private Dimension size;

	/*   ---   Constructor   ---   */

	public WaveAnimator(Image baseImage)
	{
		this.baseImage=baseImage;
		
		waveLength=0;
		amplitude =0;
		phase     =0.0;
		
		pixels=null;
	}

	/*   ---   画像生成   ---   */

	private void initFrame()
	{
		PixelGrabber grabber;
	
		size=new Dimension(baseImage.getWidth(null),
		                   baseImage.getHeight(null));
		
		pixels    =new int[size.width*size.height];
		basePixels=new int[size.width*size.height];
		
		grabber=new PixelGrabber(baseImage,0,0,size.width,size.height,
		                         basePixels,0,size.width);
		try {
			grabber.grabPixels();
		} catch (InterruptedException e) {}
	}

	private void createFrame()
	{
		double rr,d;
		int xx,yy,cx,cy;
	
		if (pixels==null) initFrame();
		
		cx=size.width /2;
		cy=size.height/2;
		for (int y=0;y<=size.height-1;y++)
		{
			for (int x=0;x<=size.width-1;x++)
			{
				rr=Math.sqrt((x-cx)*(x-cx)+(y-cy)*(y-cy));
				d=Math.sin(phase+2.0*Math.PI*rr/waveLength)*amplitude;
				if (d==0.0)
				{
					xx=x;
					yy=y;
				}
				else
				{
					xx=(int)((x-cx)*Math.max(0,rr+d)/rr)+size.width /2;
					yy=(int)((y-cy)*Math.max(0,rr+d)/rr)+size.height/2;
				}
				if (0<=xx && xx<=size.width -1 &&
				    0<=yy && yy<=size.height-1)
				{
					pixels[x+y*size.width]=basePixels[xx+yy*size.width];
				}
				else
				{
					pixels[x+y*size.width]=0;
				}
			}
		}
		if (imageSource!=null)
		{
			imageSource.newPixels(0,0,size.width,size.height);
		}
	}

	/*   ---   ImageProducer   ---   */

	public ImageProducer getImageProducer()
	{
		if (imageSource==null)
		{
			createFrame();
			imageSource=new MemoryImageSource(size.width,size.height,
			                                  pixels,0,size.width);
			imageSource.setAnimated(true);
		}
		return imageSource;
	}

	/*   ---   アニメーション   ---   */

	public void nextFrame(int waveLength,int amplitude,double phase)
	{
		this.waveLength=waveLength;
		this.amplitude =amplitude;
		this.phase     =phase;
		
		createFrame();
	}
}