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DrawingPanel.java

/*
 *  Copyright 2006-2007 Columbia University.
 *
 *  This file is part of MEAPsoft.
 *
 *  MEAPsoft is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  MEAPsoft 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 MEAPsoft; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 *  02110-1301 USA
 *
 *  See the file "COPYING" for the text of the license.
 */

/*
 * Created on Nov 17, 2006
 *
 */
package com.meapsoft.visualizer;

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;

import javax.swing.JPanel;
import javax.swing.JScrollPane;

public class DrawingPanel extends JPanel
{
        ActionListener actionListener;
        Renderer renderer;
        private BufferedImage image;
        private JScrollPane scroller;
        
        private int origW = -1;
        private int origH = -1;
        
        private double hZoom = 1.0;
        private double wZoom = 1.0;

    private double zoomIncrement = 0.25;
        
        boolean iJustZoomed = false;
        
        public DrawingPanel(Renderer renderer, ActionListener aL)
        {
                //setSize(800, 600);
                //setPreferredSize(new Dimension(800, 600));
                this.actionListener = aL;
                this.renderer = renderer;
        }

        void setScroller(JScrollPane scroller)
        {
                this.scroller = scroller;
        }
        
        void setRenderer(Renderer renderer)
        {
                this.renderer = renderer;
                //System.out.println("using: " + this.visualizer.name);
                repaint();
        }

        public void setOrigWH(int w, int h)
        {
                origW = w;
                origH = h;      
                image = (BufferedImage)createImage(w, h);
        }
        
        public void zoomIn()
        {
                iJustZoomed = true;

        // only zoom horizontally...
                //hZoom += zoomIncrement;
                wZoom += zoomIncrement;

        // zoom out vertically so we don't need a vertical scrollbar
        hZoom = 1 - scroller.getHorizontalScrollBar().getPreferredSize().getHeight()/origH;
        
                int w = (int)Math.round(origW * wZoom);
                int h = (int)Math.round(origH * hZoom);
        
                setSize(w, h);
                setPreferredSize(new Dimension(w, h));
                image = (BufferedImage)createImage(w, h);
                scroller.revalidate();
                
                //System.out.println("hZoom: " + hZoom + " wZoom: " + wZoom);
        }
        
        public void zoomOut()
        {
                if (hZoom == 1.0 || wZoom == 1.0)
                        return;

                iJustZoomed = true;
                
        // only zoom horizontally...
                //hZoom -= zoomIncrement;
                wZoom -= zoomIncrement;
                
        // no scrollbar necessary anymore
        if(wZoom == 1.0)
            hZoom = 1.0;
        
                int w = (int)Math.round(origW * wZoom);
                int h = (int)Math.round(origH * hZoom);
                
                setSize(w, h);
                setPreferredSize(new Dimension(w, h));
                image = (BufferedImage)createImage(w, h);
                scroller.revalidate();
                
                //System.out.println("hZoom: " + hZoom + " wZoom: " + wZoom);
        }
        
        public void resetZoom()
        {
                iJustZoomed = true;
                
                hZoom = 1.0;
                wZoom = 1.0;

                int w = (int)Math.round(origW * wZoom);
                int h = (int)Math.round(origH * hZoom);
                
                setSize(w, h);
                setPreferredSize(new Dimension(w, h));
                image = (BufferedImage)createImage(w, h);
                scroller.revalidate();
                
                //System.out.println("w: " + w + " h: " + h);
        }
        
        public void paintComponent(Graphics g)
        {               
                //System.out.println("pC...");
                //first time
                if (origW == -1)
                {
                        origW = getWidth();
                        origH = getHeight();
                }
                
                int w = (int)Math.round(origW * wZoom);
                int h = (int)Math.round(origH * hZoom);
                
                if (image == null)
                {
                        //System.out.println("making new image!");
                        image = (BufferedImage)createImage(w, h);
                }
                
                //System.out.println("gW: " + getWidth() + " gH: " + getHeight() +
                         //" w: " + w + " h: " + h +
                         //" origW: " + origW + " origH: " + origH); 
                renderer.draw(image, w, h);
                g.drawImage(image, 0, 0, this);
        }
}

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