RadialSpotlight.java

package com.drawbridge.correspondance;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Point;
import java.awt.RadialGradientPaint;

public class RadialSpotlight extends Spotlight
{
	int	centerX, centerY, radius, blur;

	public RadialSpotlight(int centerX, int centerY, int radius, int blur) {
		this.centerX = centerX;
		this.centerY = centerY;
		this.radius = radius;
		this.blur = blur;
	}

	/**
	 * 
	 * @param g
	 *            Graphics
	 */
	public void paintRadialSpotlight(Graphics g)
	{
		int diameter = (radius + blur) * 2;
		Graphics2D g2 = (Graphics2D) g;
		Paint oldPaint = g2.getPaint();
		float firstStop = ((float) radius / (float) (radius + blur));
		if (firstStop <= 0.0f)
		{
			firstStop = 0.01f;
		}
		else if (firstStop >= 1.0f)
		{
			firstStop = 0.99f;
		}
		RadialGradientPaint rgp = new RadialGradientPaint(new Point(centerX, centerY),
				radius + blur,
				new float[] { 0.0f, firstStop, 1.0f },
				new Color[] { Color.white, Color.white, new Color(255, 255, 255, 0) });
		g2.setPaint(rgp);
		int xNew = centerX - (radius + blur);
		int yNew = centerY - (radius + blur);
		g2.fillRect(xNew, yNew, diameter, diameter);
		g2.setPaint(oldPaint);
	}

}