/*
* $Id: ColorUtil.java,v 1.12 2009/05/25 01:52:13 kschaefe Exp $
*
* Copyright 2004 Sun Microsystems, Inc., 4150 Network Circle,
* Santa Clara, California 95054, U.S.A. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package org.jdesktop.swingx.color;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.Paint;
import java.awt.Rectangle;
import java.awt.TexturePaint;
import java.awt.image.BufferedImage;
import javax.swing.JComponent;
/**
* A collection of utility methods for working with {@code Color}s.
*
* @author joshua.marinacci@sun.com
* @author Karl George Schaefer
*/
public class ColorUtil {
/**
* Returns a new color equal to the old one, except that there is no alpha
* (transparency) channel.
* <p>
* This method is a convenience and has the same effect as {@code
* setAlpha(color, 255)}.
*
* @param color
* the color to remove the alpha (transparency) from
* @return a new non-transparent {@code Color}
* @throws NullPointerException
* if {@code color} is {@code null}
*/
public static Color removeAlpha(Color color) {
return setAlpha(color, 255);
}
/**
* Returns a new color equal to the old one, except alpha (transparency)
* channel is set to the new value.
*
* @param color
* the color to modify
* @param alpha
* the new alpha (transparency) level. Must be an int between 0
* and 255
* @return a new alpha-applied {@code Color}
* @throws IllegalArgumentException
* if {@code alpha} is not between 0 and 255 inclusive
* @throws NullPointerException
* if {@code color} is {@code null}
*/
public static Color setAlpha(Color color, int alpha) {
if (alpha < 0 || alpha > 255) {
throw new IllegalArgumentException("invalid alpha value");
}
return new Color(
color.getRed(), color.getGreen(), color.getBlue(), alpha);
}
/**
* Returns a new color equal to the old one, except the saturation is set to
* the new value. The new color will have the same alpha (transparency) as
* the original color.
* <p>
* The color is modified using HSB calculations. The saturation must be a
* float between 0 and 1. If 0 the resulting color will be gray. If 1 the
* resulting color will be the most saturated possible form of the passed in
* color.
*
* @param color
* the color to modify
* @param saturation
* the saturation to use in the new color
* @return a new saturation-applied {@code Color}
* @throws IllegalArgumentException
* if {@code saturation} is not between 0 and 1 inclusive
* @throws NullPointerException
* if {@code color} is {@code null}
*/
public static Color setSaturation(Color color, float saturation) {
if (saturation < 0f || saturation > 1f) {
throw new IllegalArgumentException("invalid saturation value");
}
int alpha = color.getAlpha();
float[] hsb = Color.RGBtoHSB(
color.getRed(), color.getGreen(), color.getBlue(), null);
Color c = Color.getHSBColor(hsb[0], saturation, hsb[2]);
return setAlpha(c, alpha);
}
/**
* Returns a new color equal to the old one, except the brightness is set to
* the new value. The new color will have the same alpha (transparency) as
* the original color.
* <p>
* The color is modified using HSB calculations. The brightness must be a
* float between 0 and 1. If 0 the resulting color will be black. If 1 the
* resulting color will be the brightest possible form of the passed in
* color.
*
* @param color
* the color to modify
* @param brightness
* the brightness to use in the new color
* @return a new brightness-applied {@code Color}
* @throws IllegalArgumentException
* if {@code brightness} is not between 0 and 1 inclusive
* @throws NullPointerException
* if {@code color} is {@code null}
*/
public static Color setBrightness(Color color, float brightness) {
if (brightness < 0f || brightness > 1f) {
throw new IllegalArgumentException("invalid brightness value");
}
int alpha = color.getAlpha();
float[] hsb = Color.RGBtoHSB(
color.getRed(), color.getGreen(), color.getBlue(), null);
Color c = Color.getHSBColor(hsb[0], hsb[1], brightness);
return setAlpha(c, alpha);
}
/**
* Creates a {@code String} that represents the supplied color as a
* hex-value RGB triplet, including the "#". The return value is suitable
* for use in HTML. The alpha (transparency) channel is neither include nor
* used in producing the string.
*
* @param color
* the color to convert
* @return the hex {@code String}
*/
public static String toHexString(Color color) {
return "#" + Integer.toHexString(color.getRGB() | 0xFF000000).substring(2);
}
/**
* Computes an appropriate foreground color (either white or black) for the
* given background color.
*
* @param bg
* the background color
* @return {@code Color.WHITE} or {@code Color.BLACK}
* @throws NullPointerException
* if {@code bg} is {@code null}
*/
public static Color computeForeground(Color bg) {
float[] rgb = bg.getRGBColorComponents(null);
float y = .3f * rgb[0] + .59f * rgb[1] + .11f * rgb[2];
return y > .5f ? Color.BLACK : Color.WHITE;
}
/**
* Blends two colors to create a new color. The {@code origin} color is the
* base for the new color and regardless of its alpha component, it is
* treated a fully opaque (alpha 255).
*
* @param origin
* the base of the new color
* @param over
* the alpha-enabled color to add to the {@code origin} color
* @return a new color comprised of the {@code origin} and {@code over}
* colors
*/
public static Color blend(Color origin, Color over) {
if (over == null) {
return origin;
}
if (origin == null) {
return over;
}
int a = over.getAlpha();
int rb = (((over.getRGB() & 0x00ff00ff) * a)
+ ((origin.getRGB() & 0x00ff00ff) * (0xff - a))) & 0xff00ff00;
int g = (((over.getRGB() & 0x0000ff00) * a)
+ ((origin.getRGB() & 0x0000ff00) * (0xff - a))) & 0x00ff0000;
return new Color((over.getRGB() & 0xff000000) | ((rb | g) >> 8));
}
/**
* Obtain a <code>java.awt.Paint</code> instance which draws a checker
* background of black and white.
* Note: The returned instance may be shared.
* Note: This method should be reimplemented to not use a png resource.
*
* @return a Paint implementation
*/
public static Paint getCheckerPaint() {
return getCheckerPaint(Color.white,Color.gray,20);
}
public static Paint getCheckerPaint(Color c1, Color c2, int size) {
BufferedImage img = new BufferedImage(size,size,BufferedImage.TYPE_INT_ARGB);
Graphics g = img.getGraphics();
try {
g.setColor(c1);
g.fillRect(0, 0, size, size);
g.setColor(c2);
g.fillRect(0, 0, size / 2, size / 2);
g.fillRect(size / 2, size / 2, size / 2, size / 2);
} finally {
g.dispose();
}
return new TexturePaint(img,new Rectangle(0,0,size,size));
}
/**
* Draws an image on top of a component by doing a 3x3 grid stretch of the image
* using the specified insets.
* <p>
* TODO this is image related; move to GraphicsUtilities
*/
public static void tileStretchPaint(Graphics g,
JComponent comp,
BufferedImage img,
Insets ins) {
int left = ins.left;
int right = ins.right;
int top = ins.top;
int bottom = ins.bottom;
// top
g.drawImage(img,
0,0,left,top,
0,0,left,top,
null);
g.drawImage(img,
left, 0,
comp.getWidth() - right, top,
left, 0,
img.getWidth() - right, top,
null);
g.drawImage(img,
comp.getWidth() - right, 0,
comp.getWidth(), top,
img.getWidth() - right, 0,
img.getWidth(), top,
null);
// middle
g.drawImage(img,
0, top,
left, comp.getHeight()-bottom,
0, top,
left, img.getHeight()-bottom,
null);
g.drawImage(img,
left, top,
comp.getWidth()-right, comp.getHeight()-bottom,
left, top,
img.getWidth()-right, img.getHeight()-bottom,
null);
g.drawImage(img,
comp.getWidth()-right, top,
comp.getWidth(), comp.getHeight()-bottom,
img.getWidth()-right, top,
img.getWidth(), img.getHeight()-bottom,
null);
// bottom
g.drawImage(img,
0,comp.getHeight()-bottom,
left, comp.getHeight(),
0,img.getHeight()-bottom,
left,img.getHeight(),
null);
g.drawImage(img,
left, comp.getHeight()-bottom,
comp.getWidth()-right, comp.getHeight(),
left, img.getHeight()-bottom,
img.getWidth()-right, img.getHeight(),
null);
g.drawImage(img,
comp.getWidth()-right, comp.getHeight()-bottom,
comp.getWidth(), comp.getHeight(),
img.getWidth()-right, img.getHeight()-bottom,
img.getWidth(), img.getHeight(),
null);
}
public static Color interpolate(Color b, Color a, float t) {
float[] acomp = a.getRGBComponents(null);
float[] bcomp = b.getRGBComponents(null);
float[] ccomp = new float[4];
// log.fine(("a comp ");
// for(float f : acomp) {
// log.fine((f);
// }
// for(float f : bcomp) {
// log.fine((f);
// }
for(int i=0; i<4; i++) {
ccomp[i] = acomp[i] + (bcomp[i]-acomp[i])*t;
}
// for(float f : ccomp) {
// log.fine((f);
// }
return new Color(ccomp[0],ccomp[1],ccomp[2],ccomp[3]);
}
}