voronoi nose

VoronoiNose.java

package com.thomcc.nine.level.gen;
import java.awt.Image;
import java.awt.geom.Point2D;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferInt;
import java.util.ArrayList;
import java.util.Random;

import javax.swing.ImageIcon;
import javax.swing.JOptionPane;
public class VoronoiNoise {
  public final int pts;
  public ArrayList<Point2D> points;
  private Random _random;
  public int w, h;
  public VoronoiNoise(int width, int height, int pts) {
    this.pts = pts;
    w = width;
    h = height;
    _random = new Random();
    points = new ArrayList<Point2D>();
    for (int i = 0; i < pts; ++i) {
      points.add(new Point2D.Double(_random.nextDouble() * width, _random.nextDouble() * height));
    }
  }
  public Point2D nearest(double x, double y) { 
    return nearest(new Point2D.Double(x, y));
  }
  public Point2D nearest(Point2D p) {
    Point2D min = points.get(0);
    double mindist = p.distanceSq(min);
    for (Point2D pt : points) {
      double dist = p.distanceSq(pt);
      if (mindist > dist) {
        min = pt;
        mindist = dist;
      }
    }
    return min;
  }
  public double[][] calc() {
    double[][] ary = new double[h][w];
    double maxd = -1;
    for (int y = 0; y < h; ++y) {
      for (int x = 0; x < w; ++x) {
        Point2D p = new Point2D.Double(x, y);
        Point2D n = nearest(p);
        double d = p.distance(n);
        if (d > maxd) maxd = d;
        ary[y][x] = d;
      }
    }
    for (int y = 0; y < h; ++y) {
      for (int x = 0; x < w; ++x) {
        ary[y][x] /= maxd;
      }
    }
    return ary;
  }
  
  public static void main(String args[]) {
    int width = 500;
    int height = 500;
    int points = 50;
    VoronoiNoise vn = new VoronoiNoise(width, height, points);
    double[][] grid = vn.calc();
    BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    int[] pix = ((DataBufferInt) img.getRaster().getDataBuffer()).getData();
    for (int y = 0; y < width; ++y) {
      for (int x = 0; x < height; ++x) {
        //int v = (int) (255.0 * Math.sqrt(grid[y][x]));
        int v = (int) (255.0 * grid[y][x]);
        if (v < 0) {
          System.out.format("v is less than zero: %s\n", v);
          v = 0;
        }
        if (v > 255) {
          System.out.format("v is more than 255: %s\n", v);
          v = 255;
        }

        int c = v << 16 | v << 8 | v;
        pix[x + y*width] = c;
      }
    }
    JOptionPane.showMessageDialog(
        null,
        null,
        "vnoise",
        JOptionPane.YES_NO_OPTION,
        new ImageIcon(img.getScaledInstance(img.getWidth() * 1,
            img.getHeight() * 1, Image.SCALE_AREA_AVERAGING)));

  }
}