/*
* IColorDistributor.java, interface for choosing visual different colors.
* Copyright (C) 2004 - 2011 Achim Westermann.
*
* 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
*
* If you modify or optimize the code in a useful way please let me know.
* Achim.Westermann@gmx.de
*
*/
package info.monitorenter.gui.util;
/**
* An interface for distributing colors.
* <p>
*
* Implementations are keeping track of the java.awt.Color - instances they gave
* away during invocation of <code>getColor()</code>. The aim is to provide
* an interface that allows to get unique colors from. As all colors given away
* are remembered, it is possible to avoid lending the same color several times.
* <p>
* It will be tricky to implement this in a good way because of the fact that
* the ColorLessor should not be limited to a maximum amount of colors, it does
* not know how much different colors there will be asked for a priori, the
* amount of colors given away should be the most visual different and the
* background color should be especially different from all ohter colors given
* away.
* <p>
*
* @see info.monitorenter.gui.chart.Chart2D
*
* @author <a href='mailto:Achim.Westermann@gmx.de'>Achim Westermann </a>
*/
public interface IColorDistributor {
/**
* Puts the given color back into the color- space of free colors.
* <p>
* Do not forget to give your colors back if not used any more to allow the
* biggest possible visual difference of the colors given away.
* <p>
*
* @param color
* the color to give back into this color space.
*
* @see #getColor()
*/
public void freeColor(java.awt.Color color);
/**
* Returns a color, that has not been retrieved before from this instance.
* <p>
*
* @return a color, that has not been retrieved before from this instance.
*/
public java.awt.Color getColor();
/**
* Informs the IColorDistributor that a client already uses the given color.
* <p>
*
* This ensures that the IColorDistributor does never return the given color
* to clients. Furthermore implementations may use the given informations of
* the color, e.g. an IColorDistributor that tries to return always the most
* different colors (from each other).
* <p>
*
* @param color
* the color to reserve.
*/
void reserveColor(java.awt.Color color);
/**
* No other color returned from instances must come "too near" to this color
* to guarantee a good visibility of the other colors returned.
* <p>
* Calls to this method are of course optional but should be regarded in the
* computations of implemenatations.
* <p>
*
* @param background
* the background color to keep a viewable distance to.
*/
public void setBgColor(final java.awt.Color background);
}