package org.gudy.azureus2.ui.swt.components;
/*
* Created on 1-Feb-2005
* Created by James Yeh
* Copyright (C) 2004, 2005, 2006 Aelitis, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program 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 General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.widgets.Display;
/**
* Facilitates utility methods for handling SWT Colors
* @author James Yeh
*/
public final class ColorUtils
{
/**
* <p>Gets a new SWT color that has been uniformly added with delta</p>
* <p>There is range checking such that the new RGB values are 0 <= x <= 255</p>
* @param original Original color
* @param delta Delta in 8bit RGB values
* @return New color
*/
public static final Color getShade(final Color original, final int delta)
{
final RGB newRGB = new RGB(
Math.min(255, Math.max(0, original.getRed() + delta)),
Math.min(255, Math.max(0, original.getGreen() + delta)),
Math.min(255, Math.max(0, original.getBlue() + delta))
);
return new Color(Display.getDefault(), newRGB);
}
/**
* <p>Gets a new SWT color that has been uniformly added with delta</p>
* <p>If the a RGB value goes out of bounds, the delta will be applied negatively</p>
* @param original Original color
* @param delta Delta in 8bit RGB values
* @return New color
*/
public static final Color getBoundedShade(final Color original, final int delta)
{
final RGB newRGB = new RGB(
getBoundedShade(original.getRed(), delta),
getBoundedShade(original.getGreen(), delta),
getBoundedShade(original.getBlue(), delta)
);
return new Color(Display.getDefault(), newRGB);
}
/**
* <p>Gets a 8bit RGB value that has been added with delta</p>
* <p>If the RGB value goes out of bounds, the delta will be applied negatively</p>
* @param origValue Original RGB value
* @param delta Delta
* @return New RGB value
*/
private static int getBoundedShade(final int origValue, final int delta)
{
int result = origValue + delta;
if(result > 255)
{
result = origValue - delta;
if(result < 0)
{
result = origValue;
}
}
else if(result < 0)
{
result = origValue - delta;
if(result > 255)
{
result = origValue;
}
}
return result;
}
}