[vtkusers] vtkPointPicker Class

[Amy Squillacote]

Please be more specific than saying "it doesn't work". What doesn't 
work? What behavior do you see, and what behavior do you expect?

- Amy

张涛 wrote:
> Hello
> I want to use the class vtkPointPicker to pick a point in a 
> pointcloud,but it doesn't work
> Bellow is the snippet of my program,Please tell me what's the problem.
>
> #include "vtkActor.h"
> #include "vtkPolyData.h"
> #include "vtkUnstructuredGrid.h"
> #include "vtkRenderWindow.h"
> #include "vtkRenderer.h"
> #include "vtkPointPicker.h "
> #include "vtkRenderWindowInteractor.h"
> #include "vtkPolyDataMapper.h"
> #include "vtkSphereSource.h"
> #include "vtkPolyDataReader.h"
> #include "vtkPolyDataMapper.h "
> #include "vtkShrinkFilter.h"
> #include "vtkDataSetMapper.h"
> #include "vtkRenderWindowInteractor.h"
> #include "vtkIdList.h"
>
> static void PickCells(void *);
> static vtkActor *sphereActor;
> static vtkPolyData *plateOutput;
> static vtkUnstructuredGrid *cells;
> static vtkRenderWindow *renWin;
> static vtkActor *cellsActor, *plateActor;
>
> //#include "SaveImage.h"
>
> int main( int argc, char *argv[] )
> {
>   vtkRenderer *renderer = vtkRenderer::New();
>   renWin = vtkRenderWindow::New();
>     renWin->AddRenderer(renderer);
>
>   vtkPointPicker *picker = vtkPointPicker::New();
>     picker->SetTolerance(0.01);
>
>   vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New();
>     iren->SetRenderWindow(renWin);
>     iren->SetPicker(picker);
>
>   // read data file
> //  vtkPolyDataReader *plate = vtkPolyDataReader::New();
>  //   plate->SetFileName("../../../vtkdata/plate.vtk");
>     //plate->DebugOn();
>  int t,s;
>  s = 0;
>  FILE *fpread;
>  float point[3];
>  fpread = fopen("Inspection_Three.dat","r");
>  vtkPolyData *PolyData = vtkPolyData::New();
>  vtkPoints *pointsData = vtkPoints::New();
>  vtkCellArray *PointsArray = vtkCellArray::New();
>  while(!feof(fpread))
>  {
>   for(t = 0;t < 3;t++)
>   {
>    fscanf(fpread,"%f",&point[t]);
>   }
>   pointsData->InsertPoint(s,point[0],point[1],point[2]);
>   
>   PointsArray->InsertNextCell(1);
>   PointsArray->InsertCellPoint(s);
>
>   s++;
>  }
>
>  fclose(fpread);
> // PolyData->SetPoints(pointsData);
> // PolyData->SetVerts(PointsArray);
>    // plateOutput = plate->GetOutput();
>  plateOutput = vtkPolyData::New();
>  plateOutput->SetPoints(pointsData);
>  plateOutput->SetVerts(PointsArray);
>   vtkPolyDataMapper *plateMapper = vtkPolyDataMapper::New();
>     plateMapper->SetInput(plateOutput);
>   plateActor = vtkActor::New();
>     plateActor->SetMapper(plateMapper);
>     plateActor->GetProperty()->SetColor(0.5000,0.5400,0.5300);
>
>   // create marker for pick
>   vtkSphereSource *sphere = vtkSphereSource::New();
>     sphere->SetThetaResolution(8); sphere->SetPhiResolution(8);
>     sphere->SetRadius(0.01);
>   vtkPolyDataMapper *sphereMapper = vtkPolyDataMapper::New();
>     sphereMapper->SetInput(sphere->GetOutput());
>   sphereActor = vtkActor::New();
>     sphereActor->SetMapper(sphereMapper);
>     sphereActor->GetProperty()->SetColor(1,0,0);
>     sphereActor->PickableOff();
>
>   // create actor and mapper to display picked cells
>   cells = vtkUnstructuredGrid::New();
>   vtkShrinkFilter *shrink = vtkShrinkFilter::New();
>     shrink->SetInput(cells);
>     shrink->SetShrinkFactor( 0.75);
>   vtkDataSetMapper *cellsMapper = vtkDataSetMapper::New();
>     cellsMapper->SetInput(shrink->GetOutput());
>   cellsActor = vtkActor::New();
>     cellsActor->SetMapper(cellsMapper);
>     cellsActor->PickableOff();
>     cellsActor->VisibilityOff();
>     cellsActor->GetProperty()->SetColor(0.5000,0.5400,0.5300);
>
>   renderer->AddActor(cellsActor);
>   renderer->AddActor(plateActor);
> //  renderer->AddActor(sphereActor);
>   renderer->SetBackground(1,1,1);
>   renderer->GetActiveCamera()->Elevation(30.0);
>   renderer->GetActiveCamera()->Azimuth(30.0);
>   renderer->GetActiveCamera()->Zoom(0.75);
>
>   renWin->SetSize(300,300);
>
>   // interact with data
>   renWin->Render();
>
> //  SAVEIMAGE( renWin );
>
>   iren->SetEndPickMethod(PickCells,(void *)iren);
>   iren->Start();
>
>   // Clean up
>   renderer->Delete();
>   renWin->Delete();
>   picker->Delete();
>   iren->Delete();
> //  plate->Delete();
>   plateMapper->Delete();
>   plateActor->Delete();
>   sphere->Delete();
>   sphereMapper->Delete();
>   sphereActor->Delete();
>   cells->Delete();
>   shrink->Delete();
>   cellsMapper->Delete();
>   cellsActor->Delete();
> }
>
> static void PickCells(void *arg)
> {
>   vtkRenderWindowInteractor *iren = (vtkRenderWindowInteractor *)arg;
>   vtkPointPicker *picker = (vtkPointPicker *)iren->GetPicker();
>   int i, cellId;
>   vtkIdList *cellIds = vtkIdList::New(); cellIds->Allocate(12);
>   vtkIdList *ptIds = vtkIdList::New(); ptIds->Allocate(12);
>
>   sphereActor->SetPosition(picker->GetPickPosition());
>
>   if ( picker->GetPointId() >= 0 )
>     {
>     cout << "Point id: " << picker->GetPointId() << "\n";
>     cellsActor->VisibilityOn();
>     plateActor->VisibilityOff();
>
>     cells->Initialize();
>     cells->Allocate(100);
>     cells->SetPoints(plateOutput->GetPoints());
>
>     plateOutput->GetPointCells(picker->GetPointId(), cellIds);
>     for (i=0; i < cellIds->GetNumberOfIds(); i++)
>       {
>       cellId = cellIds->GetId(i);
>       plateOutput->GetCellPoints(cellId, ptIds);
>       cells->InsertNextCell(plateOutput->GetCellType(cellId), ptIds);
>       }
>     }
>   else
>     {
>     cellsActor->VisibilityOff();
>     plateActor->VisibilityOn();
>     }
>
>   renWin->Render();
>   cellIds->Delete();
>   ptIds->Delete();
> }
>
>
>  
>
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-- 
Amy Squillacote
Kitware, Inc.
28 Corporate Drive
Clifton Park, NY 12065
Phone: (518) 371-3971 x106