bundles/org.simantics.graphviz/src/org/simantics/graphviz/drawable/ViewerCanvas.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
   3  * in Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.graphviz.drawable;
  13
  14 import java.awt.Canvas;
  15 import java.awt.Color;
  16 import java.awt.Graphics;
  17 import java.awt.Graphics2D;
  18 import java.awt.Point;
  19 import java.awt.RenderingHints;
  20 import java.awt.event.ComponentAdapter;
  21 import java.awt.event.ComponentEvent;
  22 import java.awt.event.KeyAdapter;
  23 import java.awt.event.KeyEvent;
  24 import java.awt.event.MouseAdapter;
  25 import java.awt.event.MouseEvent;
  26 import java.awt.event.MouseWheelEvent;
  27 import java.awt.event.MouseWheelListener;
  28 import java.awt.geom.AffineTransform;
  29 import java.awt.geom.Rectangle2D;
  30 import java.awt.image.VolatileImage;
  31
  32 /**
  33  * A canvas showing a given Drawable.
  34  *
  35  * @author Hannu Niemist�
  36  */
  37 public class ViewerCanvas extends Canvas {
  38
  39     private static final long serialVersionUID = -1094658958968314511L;
  40
  41     AffineTransform transform;
  42     Point prev;
  43     VolatileImage im;
  44
  45     Drawable drawable;
  46
  47     public ViewerCanvas(Drawable drawable) {
  48         this.drawable = drawable;
  49         setBackground(Color.WHITE);
  50         addKeyListener(new KeyAdapter() {
  51
  52             @Override
  53             public void keyPressed(KeyEvent e) {
  54                 if(e.getKeyChar()=='1') {
  55                     fit();
  56                     repaint();
  57                 }
  58             }
  59
  60         });
  61         addMouseListener(new MouseAdapter() {
  62
  63             @Override
  64             public void mousePressed(MouseEvent e) {
  65                 prev = e.getPoint();
  66             }
  67         });
  68         addMouseMotionListener(new MouseAdapter() {
  69             @Override
  70             public void mouseDragged(MouseEvent e) {
  71                 Point cur = e.getPoint();
  72                 double deltaX = cur.getX()-prev.getX();
  73                 double deltaY = cur.getY()-prev.getY();
  74                 transform.preConcatenate(AffineTransform.getTranslateInstance(deltaX, deltaY));
  75                 repaint();
  76                 prev = cur;
  77             }
  78         });
  79         addMouseWheelListener(new MouseWheelListener() {
  80
  81             @Override
  82             public void mouseWheelMoved(MouseWheelEvent e) {
  83                 if(transform != null) {
  84                     double scale = Math.exp(-0.1*e.getUnitsToScroll());
  85                     Point p = e.getPoint();
  86                     AffineTransform mod = new AffineTransform();
  87                     mod.translate(p.getX(), p.getY());
  88                     mod.scale(scale, scale);
  89                     mod.translate(-p.getX(), -p.getY());
  90                     transform.preConcatenate(mod);
  91                     repaint();
  92                 }
  93             }
  94
  95         });
  96         addComponentListener(new ComponentAdapter() {
  97             @Override
  98             public void componentResized(ComponentEvent e) {
  99                 if(getWidth() > 0 && getHeight() > 0) {
 100                         im = createVolatileImage(getWidth(), getHeight());
 101                         repaint();
 102                 }
 103             }
 104         });
 105     }
 106
 107     public void fit() {
 108         Rectangle2D bounds = drawable.getBounds();
 109
 110         Rectangle2D container = getBounds();
 111         double scale = Math.min(
 112             container.getWidth() / bounds.getWidth(),
 113             container.getHeight() / bounds.getHeight());
 114
 115         transform = new AffineTransform(
 116             scale, 0.0,
 117             0.0, scale,
 118             container.getX() + container.getWidth() * 0.5 - bounds.getCenterX() * scale,
 119             container.getY() + container.getHeight() * 0.5 - bounds.getCenterY() * scale
 120         );
 121     }
 122
 123     @Override
 124     public void paint(Graphics _g) {
 125         do {
 126                 if (im == null || im.validate(getGraphicsConfiguration()) ==
 127                         VolatileImage.IMAGE_INCOMPATIBLE) {
 128                     im = createVolatileImage(getWidth(), getHeight());
 129                 }
 130
 131                 Graphics2D g = (Graphics2D)im.getGraphics();
 132
 133                 g.clearRect(0, 0, im.getWidth(null), im.getHeight(null));
 134
 135                 g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
 136                 g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
 137                 g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
 138
 139                 if(transform == null)
 140                     fit();
 141                 g.setTransform(transform);
 142
 143                 drawable.draw(g, null);
 144             g.dispose();
 145         } while(im.contentsLost());
 146
 147         _g.drawImage(im, 0, 0, this);
 148     }
 149
 150     @Override
 151     public void update(Graphics g) {
 152         paint(g);
 153     }
 154
 155     public AffineTransform getTransform() {
 156         return transform;
 157     }
 158
 159 }
 160