AreaPicking
VTKExamples/Cxx/Picking/AreaPicking
Description
This example creates 3 points+vertices. Currently, the address of the picked prop is 0 (this is not correct). A red bounding box is drawn around every picked prop.
-
For '''vtkInteractorStyleTrackballCamera''' - use 'p' to pick at the current mouse position
-
For '''vtkInteractorStyleRubberBandPick''' - use 'r' and left-mouse to draw a selection box used to pick
Code
AreaPicking.cxx
#include <vtkVersion.h>
#include <vtkSmartPointer.h>
#include <vtkPoints.h>
#include <vtkXMLPolyDataWriter.h>
#include <vtkPolyData.h>
#include <vtkCellArray.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkInteractorStyleRubberBandPick.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkInteractorStyleTrackball.h>
#include <vtkAreaPicker.h>
#include <vtkCallbackCommand.h>
#include <vtkProp3DCollection.h>
void PickCallbackFunction ( vtkObject* caller, long unsigned int eventId, void* clientData, void* callData );
int main(int, char *[])
{
// Create a set of points
vtkSmartPointer<vtkPoints> points =
vtkSmartPointer<vtkPoints>::New();
vtkSmartPointer<vtkCellArray> vertices =
vtkSmartPointer<vtkCellArray>::New();
vtkIdType pid[1];
pid[0] = points->InsertNextPoint ( 1.0, 0.0, 0.0 );
vertices->InsertNextCell ( 1,pid );
pid[0] = points->InsertNextPoint ( 0.0, 0.0, 0.0 );
vertices->InsertNextCell ( 1,pid );
pid[0] = points->InsertNextPoint ( 0.0, 1.0, 0.0 );
vertices->InsertNextCell ( 1,pid );
// Create a polydata
vtkSmartPointer<vtkPolyData> polydata =
vtkSmartPointer<vtkPolyData>::New();
polydata->SetPoints ( points );
polydata->SetVerts ( vertices );
// Visualize
vtkSmartPointer<vtkPolyDataMapper> mapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
#if VTK_MAJOR_VERSION <= 5
mapper->SetInput(polydata);
#else
mapper->SetInputData(polydata);
#endif
vtkSmartPointer<vtkActor> actor =
vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
vtkSmartPointer<vtkAreaPicker> areaPicker =
vtkSmartPointer<vtkAreaPicker>::New();
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
renderWindowInteractor->SetPicker(areaPicker);
renderer->AddActor(actor);
renderer->SetBackground(0,0,0.2); // Background color dark blue
renderWindow->Render();
// For vtkInteractorStyleRubberBandPick - use 'r' and left-mouse to draw a selection box used to pick
//vtkSmartPointer<vtkInteractorStyleRubberBandPick> style =
//vtkSmartPointer<vtkInteractorStyleRubberBandPick>::New();
// For vtkInteractorStyleTrackballCamera - use 'p' to pick at the current mouse position
vtkSmartPointer<vtkInteractorStyleTrackballCamera> style =
vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New(); //like paraview
style->SetCurrentRenderer(renderer);
renderWindowInteractor->SetInteractorStyle( style );
vtkSmartPointer<vtkCallbackCommand> pickCallback =
vtkSmartPointer<vtkCallbackCommand>::New();
pickCallback->SetCallback ( PickCallbackFunction );
areaPicker->AddObserver ( vtkCommand::EndPickEvent, pickCallback );
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
void PickCallbackFunction(vtkObject* caller,
long unsigned int vtkNotUsed(eventId),
void* vtkNotUsed(clientData),
void* vtkNotUsed(callData))
{
std::cout << "Pick." << std::endl;
vtkAreaPicker* areaPicker = static_cast<vtkAreaPicker*>(caller);
vtkProp3DCollection* props = areaPicker->GetProp3Ds();
for(vtkIdType i = 0; i < props->GetNumberOfItems(); i++)
{
vtkProp3D* prop = props->GetNextProp3D();
std::cout << "Picked prop: " << prop << std::endl;
}
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(AreaPicking)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(AreaPicking MACOSX_BUNDLE AreaPicking.cxx)
target_link_libraries(AreaPicking ${VTK_LIBRARIES})
Download and Build AreaPicking
Click here to download AreaPicking and its CMakeLists.txt file. Once the tarball AreaPicking.tar has been downloaded and extracted,
cd AreaPicking/build
If VTK is installed:
cmake ..
If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:
cmake -DVTK_DIR:PATH=/home/me/vtk_build ..
Build the project:
make
and run it:
./AreaPicking
WINDOWS USERS PLEASE NOTE: Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.