/*   加算重ねあわせ ImageFilter  Ver 0.00   */
/*                                          */
/*                                          */
/*   by Atsushi                   98/4/16   */


package net.antun.lib.awt.image;

import java.awt.*;
import java.awt.image.PixelGrabber;
import java.awt.image.RGBImageFilter;


public class AdditionImageFilter extends RGBImageFilter
{
	/*   ---   Field   ---   */

	private Image image;
	private int ox,oy;

	private PixelGrabber grabber;
	private Dimension imageSize;
	private int pixels[];

	/*   ---   Constructor   ---   */

	public AdditionImageFilter(Image image,int x,int y)
	{
		this.image=image;
		this.ox   =x;
		this.oy   =y;
	}

	/*   ---   準備   ---   */

	public void setDimensions(int width,int height)
	{
		super.setDimensions(width,height);
		
		imageSize=new Dimension(image.getWidth(null),image.getHeight(null));
		pixels=new int[imageSize.width*imageSize.height];
		grabber=new PixelGrabber(image,0,0,imageSize.width,imageSize.height,
		                         pixels,0, imageSize.width);
		
		try {
			grabber.grabPixels();
		} catch (InterruptedException e) {}
	}

	/*   ---   フィルタリング   ---   */

	public int filterRGB(int x,int y,int rgb)
	{
		int rgb2,r,g,b;
		int xx,yy;
	
		xx=x-ox;
		yy=y-oy;
		if (0<=xx && xx<=imageSize.width-1 && 0<=yy && yy<=imageSize.height-1)
		{
			rgb2=pixels[xx+yy*imageSize.width];
			
			r=Math.min(((rgb >>16) & 0xff)+((rgb2>>16) & 0xff),255);
			g=Math.min(((rgb >> 8) & 0xff)+((rgb2>> 8) & 0xff),255);
			b=Math.min(((rgb >> 0) & 0xff)+((rgb2>> 0) & 0xff),255);
			
			return (0xff000000 | (r<<16) | (g<<8) | (b<<0));
		}
		else
		{
			return rgb;
		}
	}

	/*   ---   文字列化   ---   */

	public String toString()
	{
		return getClass().getName()+"[x="+ox+",y="+oy+"]";
	}
}