healthbar.java

用java开发的一个实施策略游戏源码 值得学习一下

/*
	Netwar
	Copyright (C) 2002  Daniel Grund, Kyle Kakligian, Jason Komutrattananon, & Brian Hibler.

	This file is part of Netwar.

	Netwar 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.

	Netwar 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 Netwar; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

package netwar.gui;
import java.awt.*;
import netwar.game.GameObject;
import netwar.utils.vectorgraphics.MalleableColor;
import netwar.utils.vectorgraphics.ColorSpectrum;

/** This class is a stripped down, streamlined health bar display. */
class HealthBar extends Component {
    GameObject current = null;
    static Color back = new Color(64, 64, 64);
    //I know some of the colors are outside [0,255].
    //I added a new feature to ColorSpectrum that makes it deal with these.
    //So, the lower half will have red clipped down to 255 and the upper half will have green = 255.
    //Thus, it goes red -> yellow -> green.
    static ColorSpectrum redToGreen = new ColorSpectrum(510, 0, 0, 510, 0, 0, 255, 255, 101);
    static MalleableColor fore = new MalleableColor(redToGreen);
    
    public HealthBar() {
    }

    public void update(Graphics g) {
        paint(g);
    }
    
    public void paint(Graphics g) {
        int h = getHeight();
        int w = getWidth();
        int x;
        float f;
        if(current == null)
            f = 0;
        else
            f = current.getStatusFraction();
        fore.setCurrent(((int)(f * 100)) + 1);
        x = (int)(f * w);
        g.setColor(fore);
        g.fillRect(0, 0, x, h);
        g.setColor(back);
        g.fillRect(x, 0, w - x, h);
    }
}