Shadows.java

package ij.plugin.filter;
import ij.*;
import ij.gui.*;
import ij.process.*;
import java.awt.*;

public class Shadows implements PlugInFilter {
    
    String arg;
    ImagePlus imp;

    public int setup(String arg, ImagePlus imp) {
        this.arg = arg;
        this.imp = imp;
        if (imp!=null && imp.getStackSize()>1 && arg.equals("demo"))
            {IJ.error("This demo does not work with stacks."); return DONE;}
        return IJ.setupDialog(imp, DOES_ALL+SUPPORTS_MASKING);
    }

    public void run(ImageProcessor ip) {
        if (arg.equals("north")) north(ip);
        else if (arg.equals("northeast")) northeast(ip);
        else if (arg.equals("east")) east(ip);
        else if (arg.equals("southeast")) southeast(ip);
        else if (arg.equals("south")) south(ip);
        else if (arg.equals("southwest")) southwest(ip);
        else if (arg.equals("west")) west(ip);
        else if (arg.equals("northwest")) northwest(ip);

    }
        
        
        public void north(ImageProcessor ip) {
            int[] kernel = {1,2,1, 0,1,0,  -1,-2,-1};
            ip.convolve3x3(kernel);
        }

        public void south(ImageProcessor ip) {
            int[] kernel = {-1,-2,-1,  0,1,0,  1,2,1};
            ip.convolve3x3(kernel);
        }

        public void east(ImageProcessor ip) {
            int[] kernel = {-1,0,1,  -2,1,2,  -1,0,1};
            ip.convolve3x3(kernel);
        }

        public void west(ImageProcessor ip) {
            int[] kernel = {1,0,-1,  2,1,-2,  1,0,-1};
            ip.convolve3x3(kernel);
        }

        public void northwest(ImageProcessor ip) {
            int[] kernel = {2,1,0,  1,1,-1,  0,-1,-2};
            ip.convolve3x3(kernel);
        }

        public void southeast(ImageProcessor ip) {
            int[] kernel = {-2,-1,0,  -1,1,1,  0,1,2};
            ip.convolve3x3(kernel);
        }
        
        public void northeast(ImageProcessor ip) {
            int[] kernel = {0,1,2,  -1,1,1,  -2,-1,0};
            ip.convolve3x3(kernel);
        }
        
        public void southwest(ImageProcessor ip) {
            int[] kernel = {0,-1,-2,  1,1,-1,  2,1,0};
            ip.convolve3x3(kernel);
        }
}