bundles/org.simantics.g2d/src/org/simantics/g2d/participant/OrientationRestorer.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.g2d.participant;
  13
  14 import java.awt.geom.Point2D;
  15 import java.awt.geom.Rectangle2D;
  16 import java.util.Timer;
  17 import java.util.TimerTask;
  18
  19 import org.simantics.g2d.canvas.Hints;
  20 import org.simantics.g2d.canvas.ICanvasContext;
  21 import org.simantics.g2d.canvas.impl.AbstractCanvasParticipant;
  22 import org.simantics.g2d.canvas.impl.DependencyReflection.Dependency;
  23 import org.simantics.g2d.canvas.impl.HintReflection.HintListener;
  24 import org.simantics.utils.datastructures.disposable.DisposeState;
  25 import org.simantics.utils.datastructures.hints.IHintObservable;
  26 import org.simantics.utils.datastructures.hints.IHintContext.Key;
  27 import org.simantics.utils.threads.IThreadWorkQueue;
  28
  29 /**
  30  * Restores orientation of the canvas back to normal (north is up)
  31  *
  32  *
  33  * @author Toni Kalajainen
  34  */
  35 public class OrientationRestorer extends AbstractCanvasParticipant {
  36
  37     @Dependency
  38     TransformUtil           util;
  39     @Dependency
  40     CanvasGrab              grab;
  41     @Dependency
  42     CanvasBoundsParticipant bounds;
  43
  44     long                    lastTrigger;
  45     Point2D                 centerPoint        = new Point2D.Double();
  46
  47     transient Timer         timer              = new Timer("Rotate restore");
  48     transient boolean       checkRotatePending = false;
  49
  50     TimerTask               task               = new TimerTask() {
  51         @Override
  52         public void run() {
  53             ICanvasContext ctx = getContext();
  54             if (ctx.getDisposeState() != DisposeState.Alive)
  55                 return;
  56             IThreadWorkQueue thread = ctx.getThreadAccess();
  57             if (thread == null)
  58                 return;
  59             thread.asyncExec(new Runnable() {
  60                 @Override
  61                 public void run() {
  62                     if (checkRotatePending)
  63                         return;
  64                     checkRotatePending = true;
  65                     timerEvent();
  66                 }
  67             });
  68         }
  69     };
  70
  71     @Override
  72     public void removedFromContext(ICanvasContext ctx) {
  73         timer.cancel();
  74         super.removedFromContext(ctx);
  75     }
  76
  77     @Override
  78     public void addedToContext(ICanvasContext ctx) {
  79         super.addedToContext(ctx);
  80         long delay = 1000 / 25;
  81         lastTrigger = System.currentTimeMillis();
  82         timer.scheduleAtFixedRate(task, delay, delay);
  83     }
  84
  85     @HintListener(Class = Hints.class, Field = "KEY_CANVAS_BOUNDS")
  86     public void selectionChanged(IHintObservable sender, Key key, Object oldValue, Object newValue) {
  87         Rectangle2D cb = (Rectangle2D) newValue;
  88         this.centerPoint.setLocation(cb.getCenterX(), cb.getCenterY());
  89     }
  90
  91     void timerEvent() {
  92         ICanvasContext ctx = getContext();
  93         if (ctx == null)
  94             return;
  95         if (ctx.getDisposeState() != DisposeState.Alive)
  96             return;
  97         long cur = System.currentTimeMillis();
  98         long delta = cur - lastTrigger;
  99         lastTrigger = cur;
 100         checkRotatePending = false;
 101
 102         Point2D centerPoint = new Point2D.Double();
 103         int grabCount = grab.grabInfo.size();
 104         if (grabCount == 0) {
 105             centerPoint = this.centerPoint;
 106         } else if (grabCount == 1) {
 107             centerPoint = grab.grabInfo.values().iterator().next().anchorPos;
 108         } else {
 109             angVel = 0.0;
 110             return;
 111         }
 112
 113         // turn the canvas a bit
 114         double theta = util.getRotate();
 115         if (theta == 0.0)
 116             return;
 117 //        if (Math.abs(theta) < 0.0001) {
 118 //            angVel = 0.0;
 119 //            return;
 120 //        }
 121         if (Math.abs(theta) < 0.001) {
 122             util.restoreOrientation(centerPoint);
 123             angVel = 0.0;
 124             return;
 125         }
 126
 127         double momentum = theta * 100;
 128         double dt = ((double) delta) / 1000;
 129         if (dt > 0.150)
 130             dt = 0.150;
 131         angVel += momentum * dt;
 132         util.rotate(centerPoint, -angVel * dt);
 133         angVel *= 0.5;
 134     }
 135
 136     double angVel = 0.0;
 137
 138 }