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.concurrent.Executors;
  17 import java.util.concurrent.ScheduledExecutorService;
  18 import java.util.concurrent.TimeUnit;
  19
  20 import org.simantics.g2d.canvas.Hints;
  21 import org.simantics.g2d.canvas.ICanvasContext;
  22 import org.simantics.g2d.canvas.impl.AbstractCanvasParticipant;
  23 import org.simantics.g2d.canvas.impl.DependencyReflection.Dependency;
  24 import org.simantics.g2d.canvas.impl.HintReflection.HintListener;
  25 import org.simantics.utils.datastructures.disposable.DisposeState;
  26 import org.simantics.utils.datastructures.hints.IHintContext.Key;
  27 import org.simantics.utils.datastructures.hints.IHintObservable;
  28 import org.simantics.utils.threads.IThreadWorkQueue;
  29
  30 /**
  31  * Restores orientation of the canvas back to normal (north is up)
  32  *
  33  *
  34  * @author Toni Kalajainen
  35  */
  36 public class OrientationRestorer extends AbstractCanvasParticipant {
  37
  38     @Dependency
  39     TransformUtil           util;
  40     @Dependency
  41     CanvasGrab              grab;
  42     @Dependency
  43     CanvasBoundsParticipant bounds;
  44
  45     long                    lastTrigger;
  46     Point2D                 centerPoint        = new Point2D.Double();
  47
  48     transient ScheduledExecutorService         timer              = Executors.newSingleThreadScheduledExecutor();
  49     transient boolean       checkRotatePending = false;
  50
  51     Runnable               task               = new Runnable() {
  52         @Override
  53         public void run() {
  54             ICanvasContext ctx = getContext();
  55             if (ctx.getDisposeState() != DisposeState.Alive)
  56                 return;
  57             IThreadWorkQueue thread = ctx.getThreadAccess();
  58             if (thread == null)
  59                 return;
  60             thread.asyncExec(new Runnable() {
  61                 @Override
  62                 public void run() {
  63                     if (checkRotatePending)
  64                         return;
  65                     checkRotatePending = true;
  66                     timerEvent();
  67                 }
  68             });
  69         }
  70     };
  71
  72     @Override
  73     public void removedFromContext(ICanvasContext ctx) {
  74         timer.shutdown();
  75         try {
  76             if (!timer.awaitTermination(1, TimeUnit.SECONDS)) {
  77                 timer.shutdownNow();
  78             }
  79         } catch (InterruptedException e) {
  80             // Ignore
  81         }
  82         super.removedFromContext(ctx);
  83     }
  84
  85     @Override
  86     public void addedToContext(ICanvasContext ctx) {
  87         super.addedToContext(ctx);
  88 //        long delay = 1000 / 25; this sounds quite frequent
  89         long delay = 1000 / 10;
  90         lastTrigger = System.currentTimeMillis();
  91         timer.scheduleAtFixedRate(task, delay, delay, TimeUnit.MILLISECONDS);
  92     }
  93
  94     @HintListener(Class = Hints.class, Field = "KEY_CANVAS_BOUNDS")
  95     public void selectionChanged(IHintObservable sender, Key key, Object oldValue, Object newValue) {
  96         Rectangle2D cb = (Rectangle2D) newValue;
  97         this.centerPoint.setLocation(cb.getCenterX(), cb.getCenterY());
  98     }
  99
 100     void timerEvent() {
 101         ICanvasContext ctx = getContext();
 102         if (ctx == null)
 103             return;
 104         if (ctx.getDisposeState() != DisposeState.Alive)
 105             return;
 106         long cur = System.currentTimeMillis();
 107         long delta = cur - lastTrigger;
 108         lastTrigger = cur;
 109         checkRotatePending = false;
 110
 111         Point2D centerPoint = new Point2D.Double();
 112         int grabCount = grab.grabInfo.size();
 113         if (grabCount == 0) {
 114             centerPoint = this.centerPoint;
 115         } else if (grabCount == 1) {
 116             centerPoint = grab.grabInfo.values().iterator().next().anchorPos;
 117         } else {
 118             angVel = 0.0;
 119             return;
 120         }
 121
 122         // turn the canvas a bit
 123         double theta = util.getRotate();
 124         if (theta == 0.0)
 125             return;
 126 //        if (Math.abs(theta) < 0.0001) {
 127 //            angVel = 0.0;
 128 //            return;
 129 //        }
 130         if (Math.abs(theta) < 0.001) {
 131             util.restoreOrientation(centerPoint);
 132             angVel = 0.0;
 133             return;
 134         }
 135
 136         double momentum = theta * 100;
 137         double dt = ((double) delta) / 1000;
 138         if (dt > 0.150)
 139             dt = 0.150;
 140         angVel += momentum * dt;
 141         util.rotate(centerPoint, -angVel * dt);
 142         angVel *= 0.5;
 143     }
 144
 145     double angVel = 0.0;
 146
 147 }