vv/vvSlicerManagerCommand.cxx

   1 /*=========================================================================
   2   Program:   vv                     http://www.creatis.insa-lyon.fr/rio/vv
   3
   4   Authors belong to:
   5   - University of LYON              http://www.universite-lyon.fr/
   6   - Léon Bérard cancer center       http://www.centreleonberard.fr
   7   - CREATIS CNRS laboratory         http://www.creatis.insa-lyon.fr
   8
   9   This software is distributed WITHOUT ANY WARRANTY; without even
  10   the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  11   PURPOSE.  See the copyright notices for more information.
  12
  13   It is distributed under dual licence
  14
  15   - BSD        See included LICENSE.txt file
  16   - CeCILL-B   http://www.cecill.info/licences/Licence_CeCILL-B_V1-en.html
  17 ===========================================================================**/
  18 #include "vvSlicerManagerCommand.h"
  19 #include "vvSlicerManager.h"
  20
  21 #include <vtkTextProperty.h>
  22 #include <vtkRenderer.h>
  23 #include <vtkImageActor.h>
  24 #include <vtkRenderWindowInteractor.h>
  25 #include <vtkPropPicker.h>
  26 #include <vtkCamera.h>
  27 #include <vtkImageMapToWindowLevelColors.h>
  28 #include <vtkLookupTable.h>
  29 #include <vtkMath.h>
  30 #include <vtkAbstractPropPicker.h>
  31 #include <vtkAssemblyPath.h>
  32 #include <vtkCornerAnnotation.h>
  33 #include <vtkRenderWindow.h>
  34 #include <vvImage.h>
  35 #include <vtkImageReslice.h>
  36 #include "vvSlicer.h"
  37 #include "vvInteractorStyleNavigator.h"
  38 #include "vtkTransform.h"
  39
  40 #include <cmath>
  41
  42 //------------------------------------------------------------------------------
  43 vvSlicerManagerCommand::vvSlicerManagerCommand()
  44 {
  45   mStartSlicer = -1;
  46   mSlicerNumber=-1;
  47 }
  48 //------------------------------------------------------------------------------
  49
  50
  51 //------------------------------------------------------------------------------
  52 //return the num of the current slicer if visible (-1 else)
  53 int vvSlicerManagerCommand::FindSlicerNumber(vtkRenderWindow* renwin)
  54 {
  55   int rvalue;
  56   if (renwin != SM->GetSlicer(mSlicerNumber)->GetRenderWindow() ||
  57       !SM->GetSlicer(mSlicerNumber)->GetRenderer()->GetDraw())
  58     rvalue = -1;
  59   else rvalue = mSlicerNumber;
  60   //std::cerr << this << ":" << mSlicerNumber << ": " << rvalue << endl;
  61   return rvalue;
  62 }
  63 //------------------------------------------------------------------------------
  64
  65
  66 //------------------------------------------------------------------------------
  67 void vvSlicerManagerCommand::Execute(vtkObject *caller,
  68                                      unsigned long event,
  69                                      void *vtkNotUsed(callData))
  70 {
  71   //KeyPress event
  72   vvInteractorStyleNavigator *isi =
  73     dynamic_cast<vvInteractorStyleNavigator *>(caller);
  74   if (isi) {
  75     double x = isi->GetInteractor()->GetEventPosition()[0];
  76     double y = isi->GetInteractor()->GetEventPosition()[1];
  77     double z;
  78
  79     int VisibleInWindow = this->FindSlicerNumber(isi->GetInteractor()->GetRenderWindow());
  80     vtkRenderer* renderer=NULL;
  81     if (VisibleInWindow>-1)
  82       renderer=this->SM->GetSlicer(VisibleInWindow)->GetRenderer();
  83     newLandmark = false;
  84
  85
  86
  87     if (event == vtkCommand::StartPickEvent && VisibleInWindow == -1) {
  88       for (int i = 0; i < this->SM->GetNumberOfSlicers(); i++) {
  89         if (this->SM->GetSlicer(i)->GetCursorVisibility() && !this->SM->IsLinked()) {
  90           this->SM->GetSlicer(i)->SetCursorVisibility(0);
  91           this->SM->GetSlicer(i)->SetCornerAnnotationVisibility(0);
  92           this->SM->GetSlicer(i)->Render();
  93         }
  94       }
  95     }
  96     if ( VisibleInWindow > -1 ) {
  97       if (event == vtkCommand::KeyPressEvent) {
  98         std::string KeyPress = isi->GetInteractor()->GetKeySym();
  99         bool bCtrlKey = isi->GetInteractor()->GetControlKey();
 100         if (KeyPress == "Tab") {
 101           if(isi->GetInteractor()->GetShiftKey())
 102             this->SM->PrevImage(VisibleInWindow);
 103           else
 104             this->SM->NextImage(VisibleInWindow);
 105           return;
 106         }
 107         if (KeyPress == "f" || KeyPress == "F") {
 108           FlyToPosition(isi->GetInteractor(),this->SM->GetSlicer(VisibleInWindow));
 109           return;
 110         }
 111         if (KeyPress == "w") {
 112           this->SM->SetLocalColorWindowing(VisibleInWindow);
 113           return;
 114         }
 115         if (KeyPress == "0") {
 116           this->SM->SetPreset(0);
 117           this->SM->UpdateWindowLevel();
 118           return;
 119         }
 120         if (KeyPress == "1") {
 121           this->SM->SetPreset(1);
 122           this->SM->UpdateWindowLevel();
 123           return;
 124         }
 125         if (KeyPress == "2") {
 126           this->SM->SetPreset(2);
 127           this->SM->UpdateWindowLevel();
 128
 129           return;
 130         }
 131         if (KeyPress == "3") {
 132           this->SM->SetPreset(3);
 133           this->SM->UpdateWindowLevel();
 134           return;
 135         }
 136         if (KeyPress == "4") {
 137           this->SM->SetPreset(4);
 138           this->SM->UpdateWindowLevel();
 139           return;
 140         }
 141         if (KeyPress == "5") {
 142           this->SM->SetPreset(5);
 143           this->SM->UpdateWindowLevel();
 144           return;
 145         }
 146         if (KeyPress == "6") {
 147           this->SM->SetColorMap(0);
 148           this->SM->UpdateWindowLevel();
 149           return;
 150         }
 151         if (KeyPress == "7") {
 152           this->SM->SetColorMap(1);
 153           this->SM->UpdateWindowLevel();
 154           return;
 155         }
 156         if (KeyPress == "8") {
 157           this->SM->SetColorMap(2);
 158           this->SM->UpdateWindowLevel();
 159           return;
 160         }
 161         if (KeyPress == "9") {
 162           this->SM->SetColorMap(3);
 163           this->SM->UpdateWindowLevel();
 164           return;
 165         }
 166         if (KeyPress == "equal") { //keycodes are in vtkWin32RenderWindowInteractor
 167           this->SM->SetPreset(7);
 168           //this->SM->SetColorMap(1);
 169           this->SM->UpdateWindowLevel();
 170           return;
 171         }
 172         if (KeyPress == "minus") {
 173           this->SM->SetColorWindow(-this->SM->GetColorWindow());
 174           this->SM->SetColorMap(-1);
 175           this->SM->UpdateWindowLevel();
 176           return;
 177         }
 178         if (KeyPress == "c") {
 179           this->SM->ToggleContourSuperposition();
 180           this->SM->Render();
 181           return;
 182         }
 183         if (KeyPress == "l") {
 184           this->SM->ToggleInterpolation();
 185           this->SM->Render();
 186           return;
 187         }
 188         if (KeyPress == "h") {
 189           std::cout << "KeyPress == \"h\"\n";
 190           this->SM->SetCursorAndCornerAnnotationVisibility(0);
 191           this->SM->Render();
 192           return;
 193         }
 194         if (KeyPress == "x") {
 195           for(int i=0; i<SM->GetNumberOfSlicers(); i++) {
 196             SM->RemoveActor("overlay",0);
 197             SM->SetColorMap(0);
 198             SM->Render();
 199           }
 200           return;
 201         }
 202         if (KeyPress == "u") {
 203           this->SM->Reload();
 204           this->SM->Render();
 205           return;
 206         }
 207         if (KeyPress == "r" || KeyPress=="R") {
 208           this->SM->GetSlicer(VisibleInWindow)->ResetCamera();
 209           this->SM->GetSlicer(VisibleInWindow)->Render();
 210           this->SM->UpdateLinkedNavigation( this->SM->GetSlicer(VisibleInWindow) );
 211           return;
 212         }
 213         if (KeyPress == "g") {
 214           if(bCtrlKey)
 215             this->SM->GetSlicer(VisibleInWindow)->SetCurrentPosition(0,0,0,0);
 216           else {
 217             double* cursorPos = this->SM->GetSlicer(VisibleInWindow)->GetCursorPosition();
 218             this->SM->GetSlicer(VisibleInWindow)->SetCurrentPosition(
 219               cursorPos[0],cursorPos[1],cursorPos[2],cursorPos[3]);
 220           }
 221           this->SM->UpdateViews(1,VisibleInWindow);
 222           this->SM->UpdateLinked(VisibleInWindow);
 223           return;
 224         }
 225         if (KeyPress == "F5") {
 226           this->SM->GetSlicer(VisibleInWindow)->FlipHorizontalView();
 227           this->SM->GetSlicer(VisibleInWindow)->Render();
 228           return;
 229         }
 230         if (KeyPress == "F6") {
 231           this->SM->GetSlicer(VisibleInWindow)->FlipVerticalView();
 232           this->SM->GetSlicer(VisibleInWindow)->Render();
 233           return;
 234         }
 235         if (KeyPress == "Up") {
 236           this->SM->GetSlicer(VisibleInWindow)->SetSlice(this->SM->GetSlicer(VisibleInWindow)->GetSlice()+1);
 237           this->SM->UpdateSlice(VisibleInWindow);
 238         }
 239         if (KeyPress == "Down") {
 240           this->SM->GetSlicer(VisibleInWindow)->SetSlice(this->SM->GetSlicer(VisibleInWindow)->GetSlice()-1);
 241           this->SM->UpdateSlice(VisibleInWindow);
 242         }
 243         if (KeyPress == "space") {
 244           newLandmark = true;
 245         }
 246         if (KeyPress == "Left")
 247           this->SM->SetPreviousTSlice(VisibleInWindow);
 248         if (KeyPress == "Right")
 249           this->SM->SetNextTSlice(VisibleInWindow);
 250
 251         if (KeyPress == "F2") {
 252           this->SM->GetSlicer(VisibleInWindow)->GetAnnotation()->SetText(2,"Sagital\n<slice>");
 253           //this->SM->GetSlicer(VisibleInWindow)->SetSliceOrientation(0);
 254           this->SM->SetSliceOrientation(VisibleInWindow, 0);
 255           this->SM->UpdateSliceRange(VisibleInWindow);
 256         }
 257         if (KeyPress == "F3") {
 258           this->SM->GetSlicer(VisibleInWindow)->GetAnnotation()->SetText(2,"Coronal\n<slice>");
 259           //this->SM->GetSlicer(VisibleInWindow)->SetSliceOrientation(1);
 260           this->SM->SetSliceOrientation(VisibleInWindow, 1);
 261           this->SM->UpdateSliceRange(VisibleInWindow);
 262         }
 263         if (KeyPress == "F4") {
 264           this->SM->GetSlicer(VisibleInWindow)->GetAnnotation()->SetText(2,"Axial\n<slice>");
 265           //this->SM->GetSlicer(VisibleInWindow)->SetSliceOrientation(2);
 266           this->SM->SetSliceOrientation(VisibleInWindow, 2);
 267           this->SM->UpdateSliceRange(VisibleInWindow);
 268         }
 269
 270       }
 271
 272       //All type of mouse events
 273       if (event == vtkCommand::LeaveEvent) {
 274         this->SM->GetSlicer(VisibleInWindow)->SetCurrentPosition(-VTK_DOUBLE_MAX,-VTK_DOUBLE_MAX,
 275             -VTK_DOUBLE_MAX,this->SM->GetSlicer(VisibleInWindow)->GetTSlice());
 276         this->SM->GetSlicer(VisibleInWindow)->Render();
 277         return;
 278       }
 279
 280       //DD(event);
 281       // Mouse release HERE
 282       if (event == vtkCommand::EndPickEvent) {
 283         //            DD(VisibleInWindow);
 284         if (VisibleInWindow > -1)
 285           this->SM->LeftButtonReleaseEvent(VisibleInWindow);
 286         return; // no return !!!! ???
 287       }
 288
 289       if (event == vtkCommand::StartWindowLevelEvent) {
 290         mStartSlicer = -1;
 291         this->InitialWindow = this->SM->GetColorWindow();
 292         this->InitialLevel = this->SM->GetColorLevel();
 293
 294         if (VisibleInWindow > -1) {
 295           mStartSlicer = VisibleInWindow;
 296         }
 297         return;
 298       }
 299
 300       if (event == vtkCommand::EndWindowLevelEvent) {
 301         mStartSlicer = -1;
 302       }
 303
 304       if (event == vtkCommand::EndInteractionEvent) {
 305         this->SM->Picked();
 306         this->SM->UpdateLinkedNavigation(this->SM->GetSlicer(VisibleInWindow),true);
 307         return;
 308       }
 309     }
 310     if (VisibleInWindow > -1) {
 311       this->SM->Activated();
 312       this->SM->GetSlicer(VisibleInWindow)->SetCornerAnnotationVisibility(1);
 313
 314       if (event == vtkCommand::MouseWheelForwardEvent && !isi->GetInteractor()->GetControlKey()) {
 315         this->SM->Picked();
 316         this->SM->GetSlicer(VisibleInWindow)->SetSlice(this->SM->GetSlicer(VisibleInWindow)->GetSlice()+1);
 317         this->SM->UpdateSlice(VisibleInWindow);
 318       } else if (event == vtkCommand::MouseWheelForwardEvent && isi->GetInteractor()->GetControlKey()) {
 319         double factor = 2;
 320         this->Dolly(pow((double)1.1, factor),isi->GetInteractor());
 321         Execute(caller, vtkCommand::EndInteractionEvent, NULL);
 322       } else if (event == vtkCommand::MouseWheelBackwardEvent && !isi->GetInteractor()->GetControlKey()) {
 323         this->SM->Picked();
 324         this->SM->GetSlicer(VisibleInWindow)->SetSlice(this->SM->GetSlicer(VisibleInWindow)->GetSlice()-1);
 325         this->SM->UpdateSlice(VisibleInWindow);
 326       } else if (event == vtkCommand::MouseWheelBackwardEvent && isi->GetInteractor()->GetControlKey()) {
 327         double factor = -2;
 328         this->Dolly(pow((double)1.1, factor),isi->GetInteractor());
 329         Execute(caller, vtkCommand::EndInteractionEvent, NULL);
 330       }
 331       double xWorld=0;
 332       double yWorld=0;
 333       double zWorld=0;
 334
 335       //Move into World Coordinate
 336       renderer->DisplayToNormalizedDisplay(x,y);
 337       renderer->NormalizedDisplayToViewport(x,y);
 338       renderer->ViewportToNormalizedViewport(x,y);
 339       renderer->NormalizedViewportToView(x,y,z);
 340       renderer->ViewToWorld(x,y,z);
 341       switch (this->SM->GetSlicer(VisibleInWindow)->GetSliceOrientation()) {
 342       case vtkImageViewer2::SLICE_ORIENTATION_XY:
 343         xWorld = x;
 344         yWorld = y;
 345         zWorld = this->SM->GetSlicer(VisibleInWindow)->GetSlice()*
 346                  this->SM->GetSlicer(VisibleInWindow)->GetInput()->GetSpacing()[2] +
 347                  this->SM->GetSlicer(VisibleInWindow)->GetInput()->GetOrigin()[2];
 348         break;
 349
 350       case vtkImageViewer2::SLICE_ORIENTATION_XZ:
 351         xWorld = x;
 352         yWorld = this->SM->GetSlicer(VisibleInWindow)->GetSlice()*
 353                  this->SM->GetSlicer(VisibleInWindow)->GetInput()->GetSpacing()[1] +
 354                  this->SM->GetSlicer(VisibleInWindow)->GetInput()->GetOrigin()[1];
 355         zWorld = z;
 356         break;
 357
 358       case vtkImageViewer2::SLICE_ORIENTATION_YZ:
 359         xWorld = this->SM->GetSlicer(VisibleInWindow)->GetSlice()*
 360                  this->SM->GetSlicer(VisibleInWindow)->GetInput()->GetSpacing()[0] +
 361                  this->SM->GetSlicer(VisibleInWindow)->GetInput()->GetOrigin()[0];
 362         yWorld = y;
 363         zWorld = z;
 364         break;
 365       }
 366       this->SM->GetSlicer(VisibleInWindow)->SetCurrentPosition(xWorld,yWorld,zWorld,
 367           this->SM->GetSlicer(VisibleInWindow)->GetTSlice());
 368       if (newLandmark) {
 369         this->SM->AddLandmark(xWorld,yWorld,zWorld,
 370                               this->SM->GetSlicer(VisibleInWindow)->GetTSlice());
 371         this->SM->GetSlicer(VisibleInWindow)->UpdateLandmarks();
 372         this->SM->Render();
 373       }
 374       if (event == vtkCommand::PickEvent || event == vtkCommand::StartPickEvent) {
 375         this->SM->Picked();
 376         this->SM->UpdateViews(1,VisibleInWindow);
 377         this->SM->UpdateLinked(VisibleInWindow);
 378         this->SM->UpdateInfoOnCursorPosition(VisibleInWindow);
 379       } else {
 380         this->SM->GetSlicer(VisibleInWindow)->Render();
 381       }
 382       //this->SM->GetSlicer(VisibleInWindow)->SetCurrentPosition(-VTK_DOUBLE_MAX,-VTK_DOUBLE_MAX,
 383       //-VTK_DOUBLE_MAX,this->SM->GetSlicer(VisibleInWindow)->GetTSlice());
 384       //this->SM->GetSlicer(VisibleInWindow)->Render();
 385     }
 386
 387     if (event == vtkCommand::WindowLevelEvent && mStartSlicer > -1) {
 388       this->SM->GetSlicer(mStartSlicer)->SetCornerAnnotationVisibility(1);
 389       // Adjust the window level here
 390       int *size = isi->GetInteractor()->GetRenderWindow()->GetSize();
 391       double window = this->InitialWindow;
 392       double level = this->InitialLevel;
 393       double range[2];
 394       this->SM->GetImage()->GetScalarRange(range);
 395
 396       // Compute normalized delta
 397       double dx = static_cast<double>(isi->GetWindowLevelCurrentPosition()[0] -
 398                                       isi->GetWindowLevelStartPosition()[0]) / size[0];
 399       double dy = static_cast<double>(isi->GetWindowLevelStartPosition()[1] -
 400                                       isi->GetWindowLevelCurrentPosition()[1]) / size[1];
 401       //Window is exponential in nature, use exponential to avoid falling into negative numbers
 402       dx = std::exp(1.0 * (dx*fabs(dx) + dx)) ; //Quadratic behavior for more reactive interface
 403       dy = 0.15 * (dy*fabs(dy) + dy) * (range[1]-range[0]);//Quadratic behavior for more reactive interface
 404
 405       this->SM->SetColorWindow(window*dx);
 406       this->SM->SetColorLevel(level-dy);
 407       this->SM->SetPreset(6);
 408       this->SM->UpdateWindowLevel();
 409       this->SM->Render();
 410       return;
 411     }
 412   }
 413 }
 414 //------------------------------------------------------------------------------
 415
 416
 417 //------------------------------------------------------------------------------
 418 void vvSlicerManagerCommand::Dolly(double factor, vtkRenderWindowInteractor *interactor)
 419 {
 420   int VisibleInWindow = this->FindSlicerNumber(interactor->GetRenderWindow());
 421   vtkRenderer* renderer;
 422   if (VisibleInWindow>-1)
 423     renderer=this->SM->GetSlicer(VisibleInWindow)->GetRenderer();
 424   else {
 425     return;
 426   }
 427
 428   double viewFocus[4],viewPoint[4],motionVector[3], focalDepth;
 429   double oldPos[3], newPos[3], distance[2];
 430   vtkCamera *camera = renderer->GetActiveCamera();
 431   camera->GetFocalPoint(viewFocus);
 432
 433   renderer->SetWorldPoint(viewFocus[0], viewFocus[0], viewFocus[0], 1.0);
 434   renderer->WorldToDisplay();
 435   renderer->GetDisplayPoint(viewFocus);
 436
 437   focalDepth = viewFocus[2];
 438
 439   oldPos[0] = renderer->GetCenter()[0];
 440   oldPos[1] = renderer->GetCenter()[1];
 441   oldPos[2] = focalDepth;
 442
 443   distance[0] = 1/factor*
 444                 (interactor->GetEventPosition()[0]-renderer->GetCenter()[0]);
 445   distance[1] = 1/factor*
 446                 (interactor->GetEventPosition()[1]-renderer->GetCenter()[1]);
 447
 448   newPos[0] = interactor->GetEventPosition()[0] - distance[0];
 449   newPos[1] = interactor->GetEventPosition()[1] - distance[1];
 450   newPos[2] = focalDepth;
 451
 452   renderer->DisplayToNormalizedDisplay(oldPos[0],oldPos[1]);
 453   renderer->NormalizedDisplayToViewport(oldPos[0],oldPos[1]);
 454   renderer->ViewportToNormalizedViewport(oldPos[0],oldPos[1]);
 455   renderer->NormalizedViewportToView(oldPos[0],oldPos[1],oldPos[2]);
 456   renderer->ViewToWorld(oldPos[0],oldPos[1],oldPos[2]);
 457
 458   renderer->DisplayToNormalizedDisplay(newPos[0],newPos[1]);
 459   renderer->NormalizedDisplayToViewport(newPos[0],newPos[1]);
 460   renderer->ViewportToNormalizedViewport(newPos[0],newPos[1]);
 461   renderer->NormalizedViewportToView(newPos[0],newPos[1],newPos[2]);
 462   renderer->ViewToWorld(newPos[0],newPos[1],newPos[2]);
 463
 464   motionVector[0] = newPos[0] - oldPos[0];
 465   motionVector[1] = newPos[1] - oldPos[1];
 466   motionVector[2] = newPos[2] - oldPos[2];
 467
 468   camera->GetFocalPoint(viewFocus);
 469   camera->GetPosition(viewPoint);
 470   camera->SetFocalPoint(motionVector[0] + viewFocus[0],
 471                         motionVector[1] + viewFocus[1],
 472                         motionVector[2] + viewFocus[2]);
 473
 474   camera->SetPosition(motionVector[0] + viewPoint[0],
 475                       motionVector[1] + viewPoint[1],
 476                       motionVector[2] + viewPoint[2]);
 477
 478   if (camera->GetParallelProjection()) {
 479     camera->SetParallelScale(camera->GetParallelScale() / factor);
 480   } else {
 481     camera->Dolly(factor);
 482   }
 483
 484   if (interactor->GetLightFollowCamera()) {
 485     renderer->UpdateLightsGeometryToFollowCamera();
 486   }
 487   renderer->ResetCameraClippingRange();
 488   //interactor->Render();
 489 }
 490 //------------------------------------------------------------------------------
 491
 492
 493 //------------------------------------------------------------------------------
 494 void vvSlicerManagerCommand::FlyToPosition(vtkRenderWindowInteractor *interactor,vvSlicer* slicer)
 495 {
 496   double flyFrom[3], flyTo[3];
 497   double d[3], focalPt[3], position[3], positionFrom[3];
 498   int i, j;
 499   int VisibleInWindow = this->FindSlicerNumber(interactor->GetRenderWindow());
 500   vtkRenderer* renderer=NULL;
 501   if (VisibleInWindow>-1)
 502     renderer=this->SM->GetSlicer(VisibleInWindow)->GetRenderer();
 503   else
 504     return;
 505
 506   interactor->GetPicker()->Pick(interactor->GetEventPosition()[0],
 507                                 interactor->GetEventPosition()[1], 0.0,
 508                                 renderer);
 509
 510   vtkAssemblyPath *path=NULL;
 511   vtkAbstractPropPicker *picker;
 512   if ( (picker=vtkAbstractPropPicker::SafeDownCast(interactor->GetPicker()))) {
 513     path = picker->GetPath();
 514   }
 515   if ( path != NULL ) {
 516     flyTo[0] = picker->GetPickPosition()[0];
 517     flyTo[1] = picker->GetPickPosition()[1];
 518     flyTo[2] = picker->GetPickPosition()[2];
 519     renderer->GetActiveCamera()->GetFocalPoint(flyFrom);
 520     renderer->GetActiveCamera()->GetPosition(positionFrom);
 521
 522     switch (slicer->GetSliceOrientation()) {
 523     case vtkImageViewer2::SLICE_ORIENTATION_XY:
 524       flyTo[2] = flyFrom[2];
 525       break;
 526
 527     case vtkImageViewer2::SLICE_ORIENTATION_XZ:
 528       flyTo[1] = flyFrom[1];
 529       break;
 530
 531     case vtkImageViewer2::SLICE_ORIENTATION_YZ:
 532       flyTo[0] = flyFrom[0];
 533       break;
 534     }
 535
 536
 537     for (i=0; i<3; i++) {
 538       d[i] = flyTo[i] - flyFrom[i];
 539     }
 540     double distance = vtkMath::Normalize(d);
 541     double delta = distance/15;
 542
 543     for (i=1; i<=15; i++) {
 544       for (j=0; j<3; j++) {
 545         focalPt[j] = flyFrom[j] + d[j]*i*delta;
 546         position[j] = positionFrom[j] + d[j]*i*delta;
 547       }
 548       renderer->GetActiveCamera()->SetFocalPoint(focalPt);
 549       renderer->GetActiveCamera()->SetPosition(position);
 550       renderer->GetActiveCamera()->Dolly(0.3/15 + 1.0);
 551       renderer->ResetCameraClippingRange();
 552       interactor->Render();
 553     }
 554   }
 555 }
 556 //------------------------------------------------------------------------------