bundles/org.simantics.g2d/src/org/simantics/g2d/element/handler/impl/AbstractGrabbable.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
   3  * in Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.g2d.element.handler.impl;\r
  13 \r
  14 import java.awt.geom.Point2D;\r
  15 import java.util.HashMap;\r
  16 import java.util.Map;\r
  17 import java.util.Map.Entry;\r
  18 \r
  19 import org.simantics.g2d.canvas.ICanvasContext;\r
  20 import org.simantics.g2d.canvas.IMouseCaptureHandle;\r
  21 import org.simantics.g2d.diagram.participant.DiagramParticipant;\r
  22 import org.simantics.g2d.diagram.participant.ElementInteractor;\r
  23 import org.simantics.g2d.element.ElementUtils;\r
  24 import org.simantics.g2d.element.IElement;\r
  25 import org.simantics.g2d.element.handler.HandleMouseEvent;\r
  26 import org.simantics.scenegraph.g2d.events.MouseEvent;\r
  27 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonEvent;\r
  28 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonPressedEvent;\r
  29 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonReleasedEvent;\r
  30 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseClickEvent;\r
  31 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseDragBegin;\r
  32 import org.simantics.scenegraph.g2d.events.MouseEvent.MouseMovedEvent;\r
  33 import org.simantics.utils.datastructures.hints.IHintContext.Key;\r
  34 import org.simantics.utils.datastructures.hints.IHintContext.MouseSpecificKeyOf;\r
  35 \r
  36 /**\r
  37  * Base implementation for handlers that handle grabbable objects.\r
  38  * \r
  39  * TODO Esc button cancels grab\r
  40  * \r
  41  * @author Toni Kalajainen\r
  42  */\r
  43 public abstract class AbstractGrabbable implements HandleMouseEvent {\r
  44 \r
  45         private static final long serialVersionUID = -3620527648364111724L;\r
  46         Double strayDistance;\r
  47         protected int grabMouseButton = MouseEvent.LEFT_BUTTON;\r
  48         \r
  49         /**\r
  50          * Create grabbable\r
  51          * @param strayDistance stray distance or null for no limit\r
  52          */\r
  53         public AbstractGrabbable(Double strayDistance)\r
  54         {\r
  55                 this.strayDistance = strayDistance;\r
  56         }\r
  57 \r
  58         public AbstractGrabbable()\r
  59         {\r
  60                 this.strayDistance = 1000.0;\r
  61         }\r
  62         \r
  63         @Override\r
  64         public boolean handleMouseEvent(IElement e, ICanvasContext ctx, MouseEvent me) {\r
  65                 int     pointerId               = me.mouseId;\r
  66                 GrabInfo gi                             = getGrabInfo(e, ctx, pointerId);\r
  67                 \r
  68                 if ((me instanceof MouseClickEvent)||(me instanceof MouseDragBegin)) {\r
  69                         return gi!=null;                                \r
  70                 }\r
  71                 \r
  72                 if ((me instanceof MouseMovedEvent)) {\r
  73                         MouseMovedEvent mme = (MouseMovedEvent) me;\r
  74                         if (gi==null) return false;\r
  75 \r
  76                         gi.prevPosCanvas.setLocation( gi.dragPosCanvas );\r
  77                         gi.prevPosControl.setLocation( gi.dragPosControl );\r
  78                         gi.prevPosElement.setLocation( gi.dragPosElement );\r
  79                         \r
  80                         // Update drag positions\r
  81                         gi.dragPosControl.setLocation(me.controlPosition);\r
  82                         ElementUtils.controlToCanvasCoordinate(ctx, mme.controlPosition, gi.dragPosCanvas); \r
  83                         ElementUtils.controlToElementCoordinate(e, ctx, mme.controlPosition, gi.dragPosElement);\r
  84                         // Check if pointer has strayed too far, if so release grab\r
  85                         double dist = gi.dragPosControl.distance(gi.grabPosControl);                    \r
  86 \r
  87                         // Pointer has strayed too far -> release the pointer from the button\r
  88                         if (dist>strayDistance)\r
  89                         {\r
  90                                 releaseGrab(e, ctx, pointerId);\r
  91                                 onGrabCancel(gi, ctx);\r
  92                                 return true;\r
  93                         }\r
  94 \r
  95                         // Handle event\r
  96                         onDrag(gi, ctx);\r
  97                         // Consume event\r
  98                         return true;\r
  99                 }\r
 100                 \r
 101                 // Mouse released\r
 102                 if (me instanceof MouseButtonReleasedEvent)\r
 103                 {\r
 104                         MouseButtonEvent mbe = (MouseButtonEvent) me;\r
 105                         if (mbe.button != grabMouseButton) return false;\r
 106                         if (gi==null) return false;                     \r
 107                         releaseGrab(e, ctx, pointerId);\r
 108                         onRelease(gi, ctx);\r
 109                         return true;\r
 110                 }\r
 111                 // Mouse pressed\r
 112                 if (me instanceof MouseButtonPressedEvent)\r
 113                 {\r
 114                         MouseButtonEvent mbe = (MouseButtonEvent) me;\r
 115                         if (mbe.button != grabMouseButton) return false;\r
 116                         if (!onGrabCheck(e, ctx, pointerId, me.controlPosition))\r
 117                                 return false;\r
 118                         gi = grabMouse(e, ctx, pointerId, me.controlPosition);\r
 119                         onGrab(gi,ctx);\r
 120                         return true;\r
 121                 }\r
 122                 \r
 123                 return false;\r
 124         }\r
 125         \r
 126         /**\r
 127          * Checks whether grab accepted\r
 128          * @param e element\r
 129          * @param pickPos pick position in element coordinates \r
 130          * @return true if position is grabbable\r
 131          */\r
 132         protected abstract boolean onGrabCheck(IElement e, ICanvasContext ctx, int pointerId, Point2D pickPos);\r
 133         \r
 134         protected abstract void onGrab(GrabInfo gi, ICanvasContext ctx);\r
 135 \r
 136         /**\r
 137          * Event when grab is released (and not canceled)\r
 138          * Invoked after grab is released.\r
 139          * @param gi\r
 140          * @param ctx\r
 141          */\r
 142         protected abstract void onRelease(GrabInfo gi, ICanvasContext ctx);\r
 143         \r
 144         protected abstract void onDrag(GrabInfo gi, ICanvasContext ctx);\r
 145         \r
 146         /**\r
 147          * Event notified when grab is canceled. Canceling occurs automatically\r
 148          * when mouse strays too far and when user sends cancel command (presses esc) \r
 149          * \r
 150          * @param e\r
 151          * @param grabPos\r
 152          */\r
 153         protected abstract void onGrabCancel(GrabInfo gi, ICanvasContext ctx);\r
 154         \r
 155         protected void cancelGrab() {           \r
 156         }\r
 157                 \r
 158         public static class GrabInfo {\r
 159                 // Grabbed element\r
 160                 public IElement e;\r
 161                 // grabbing pointer\r
 162                 public int pointerId;\r
 163                 // Grab position\r
 164                 public Point2D grabPosControl = new Point2D.Double();\r
 165                 public Point2D grabPosCanvas = new Point2D.Double();\r
 166                 public Point2D grabPosElement = new Point2D.Double();\r
 167                 // Drag position\r
 168                 public Point2D dragPosControl = new Point2D.Double();  \r
 169                 public Point2D dragPosCanvas  = new Point2D.Double();\r
 170                 public Point2D dragPosElement = new Point2D.Double();\r
 171                 // Prev position\r
 172                 public Point2D prevPosControl = new Point2D.Double();  \r
 173                 public Point2D prevPosCanvas  = new Point2D.Double();\r
 174                 public Point2D prevPosElement = new Point2D.Double();\r
 175                 // Capture handle\r
 176                 private IMouseCaptureHandle hnd;\r
 177         }               \r
 178 \r
 179         /**\r
 180          * Remove GrabInfo object\r
 181          * @param e\r
 182          * @param ctx\r
 183          * @param pointerId\r
 184          */\r
 185         private void removeGrabInfo(IElement e, ICanvasContext ctx, int pointerId)\r
 186         {\r
 187                 DiagramParticipant dp = ctx.getSingleItem(DiagramParticipant.class);\r
 188                 Key key = new MouseSpecificKeyOf(pointerId, GrabInfo.class);\r
 189                 dp.removeElementHint(e, key);\r
 190         }\r
 191         \r
 192         /**\r
 193          * Set GrabInfo object\r
 194          * @param e\r
 195          * @param ctx\r
 196          * @param pointerId\r
 197          * @param gi\r
 198          */\r
 199         private void setGrabInfo(IElement e, ICanvasContext ctx, int pointerId, GrabInfo gi)\r
 200         {\r
 201                 DiagramParticipant dp = ctx.getSingleItem(DiagramParticipant.class);\r
 202                 Key key = new MouseSpecificKeyOf(pointerId, GrabInfo.class);\r
 203                 dp.setElementHint(e, key, gi);\r
 204                 \r
 205         }\r
 206         \r
 207         /**\r
 208          * Get GrabInfo Object\r
 209          * @param e\r
 210          * @param ctx\r
 211          * @param pointerId\r
 212          * @return\r
 213          */\r
 214         private GrabInfo getGrabInfo(IElement e, ICanvasContext ctx, int pointerId)\r
 215         {\r
 216                 DiagramParticipant dp = ctx.getSingleItem(DiagramParticipant.class);\r
 217                 Key key = new MouseSpecificKeyOf(pointerId, GrabInfo.class);            \r
 218                 return dp.getElementHint(e, key);\r
 219         }\r
 220         \r
 221         /**\r
 222          * Get all pointer grabs\r
 223          * @return\r
 224          */\r
 225         protected Map<Integer, GrabInfo> getGrabs(IElement e, ICanvasContext ctx)\r
 226         {\r
 227                 DiagramParticipant dp = ctx.getSingleItem(DiagramParticipant.class);\r
 228                 Map<Key, Object> map = dp.getElementHints(e);\r
 229                 if (map==null) return null;\r
 230                 Map<Integer, GrabInfo> result = new HashMap<Integer, GrabInfo>();\r
 231                 for (Entry<Key, Object> entry : map.entrySet())\r
 232                 {\r
 233                         if (!(entry.getValue() instanceof GrabInfo)) continue;\r
 234                         GrabInfo gi = (GrabInfo) entry.getValue();\r
 235                         result.put(gi.pointerId, gi);\r
 236                 }\r
 237                 return result;\r
 238         }       \r
 239         \r
 240         protected int getGrabCount(IElement e, ICanvasContext ctx)\r
 241         {\r
 242                 DiagramParticipant dp = ctx.getSingleItem(DiagramParticipant.class);\r
 243                 Map<Key, Object> map = dp.getElementHints(e);\r
 244                 if (map==null) return 0;\r
 245                 int result = 0;\r
 246                 for (Entry<Key, Object> entry : map.entrySet())\r
 247                 {\r
 248                         if (!(entry.getValue() instanceof GrabInfo)) continue;\r
 249                         result ++;\r
 250                 }\r
 251                 return result;\r
 252         }\r
 253         \r
 254         /**\r
 255          * Release grab of a pointer\r
 256          * @param e\r
 257          * @param ctx\r
 258          * @param pointerId\r
 259          */\r
 260         protected void releaseGrab(IElement e, ICanvasContext ctx, int pointerId)\r
 261         {\r
 262                 GrabInfo gi = getGrabInfo(e, ctx, pointerId);\r
 263                 if (gi==null) return;\r
 264                 gi.hnd.release();\r
 265                 removeGrabInfo(e, ctx, pointerId);\r
 266         }\r
 267         \r
 268         /**\r
 269          * Grab a pointer\r
 270          * @param e\r
 271          * @param ctx\r
 272          * @param pointerId\r
 273          * @param grabPointControl\r
 274          * @return\r
 275          */\r
 276         private GrabInfo grabMouse(IElement e, ICanvasContext ctx, int pointerId, Point2D grabPointControl)\r
 277         {\r
 278                 // Release previous capture, if exists\r
 279                 releaseGrab(e, ctx, pointerId);         \r
 280                 \r
 281                 ElementInteractor ei = ctx.getSingleItem(ElementInteractor.class);\r
 282                 IMouseCaptureHandle hnd = ei.captureMouse(e, pointerId);\r
 283                 if (hnd == null) return null;\r
 284 \r
 285                 Point2D grabPointCanvas = ElementUtils.controlToCanvasCoordinate(ctx, grabPointControl, new Point2D.Double());\r
 286                 Point2D grabPointElement = ElementUtils.controlToElementCoordinate(e, ctx, grabPointControl, new Point2D.Double());\r
 287                 \r
 288                 GrabInfo gi = new GrabInfo();\r
 289                 gi.e = e;\r
 290                 gi.hnd = hnd;\r
 291                 gi.pointerId = pointerId;\r
 292                 gi.grabPosControl.setLocation(grabPointControl);\r
 293                 gi.grabPosCanvas.setLocation(grabPointCanvas);\r
 294                 gi.grabPosElement.setLocation(grabPointElement);\r
 295                 \r
 296                 gi.dragPosControl.setLocation(grabPointControl);\r
 297                 gi.dragPosCanvas.setLocation(grabPointCanvas);\r
 298                 gi.dragPosElement.setLocation(grabPointElement);\r
 299                                 \r
 300                 gi.prevPosControl.setLocation(grabPointControl);\r
 301                 gi.prevPosCanvas.setLocation(grabPointCanvas);\r
 302                 gi.prevPosElement.setLocation(grabPointElement);\r
 303                 \r
 304                 setGrabInfo(e, ctx, pointerId, gi);\r
 305                 \r
 306                 return gi;\r
 307         }       \r
 308 \r
 309 }\r