VisualizeKDTree
VTKExamples/Cxx/DataStructures/VisualizeKDTree
Description
This demo shows every level of a kdTree.
Code
VisualizeKDTree.cxx
#include <vtkVersion.h>
#include <vtkPointSource.h>
#include <vtkKdTreePointLocator.h>
#include <vtkSmartPointer.h>
#include <vtkPolyData.h>
#include <vtkSliderWidget.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkPolyData.h>
#include <vtkSmartPointer.h>
#include <vtkCommand.h>
#include <vtkWidgetEvent.h>
#include <vtkCallbackCommand.h>
#include <vtkWidgetEventTranslator.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkSliderWidget.h>
#include <vtkSliderRepresentation2D.h>
#include <vtkProperty.h>
#include <vtkMath.h>
class vtkSliderCallback : public vtkCommand
{
public:
static vtkSliderCallback *New()
{
return new vtkSliderCallback;
}
vtkSliderCallback():KdTree(0), Level(0), PolyData(0), Renderer(0){}
virtual void Execute(vtkObject *caller, unsigned long, void*)
{
vtkSliderWidget *sliderWidget =
reinterpret_cast<vtkSliderWidget*>(caller);
this->Level = vtkMath::Round(static_cast<vtkSliderRepresentation *>(sliderWidget->GetRepresentation())->GetValue());
this->KdTree->GenerateRepresentation(this->Level, this->PolyData);
this->Renderer->Render();
}
vtkKdTreePointLocator* KdTree;
int Level;
vtkPolyData* PolyData;
vtkRenderer* Renderer;
};
int main (int, char *[])
{
// Create a point cloud
vtkSmartPointer<vtkPointSource> pointSource =
vtkSmartPointer<vtkPointSource>::New();
pointSource->SetRadius(4);
pointSource->SetNumberOfPoints(1000);
pointSource->Update();
vtkSmartPointer<vtkPolyDataMapper> pointsMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
pointsMapper->SetInputConnection(pointSource->GetOutputPort());
vtkSmartPointer<vtkActor> pointsActor =
vtkSmartPointer<vtkActor>::New();
pointsActor->SetMapper(pointsMapper);
pointsActor->GetProperty()->SetInterpolationToFlat();
int maxLevel = 20;
// Create the tree
vtkSmartPointer<vtkKdTreePointLocator> kdTree =
vtkSmartPointer<vtkKdTreePointLocator>::New();
kdTree->SetDataSet(pointSource->GetOutput());
kdTree->AutomaticOff();
kdTree->SetMaxLevel(maxLevel);
kdTree->BuildLocator();
// Initialize the representation
vtkSmartPointer<vtkPolyData> polydata =
vtkSmartPointer<vtkPolyData>::New();
kdTree->GenerateRepresentation(0, polydata);
vtkSmartPointer<vtkPolyDataMapper> octreeMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
#if VTK_MAJOR_VERSION <= 5
octreeMapper->SetInputConnection(polydata->GetProducerPort());
#else
octreeMapper->SetInputData(polydata);
#endif
vtkSmartPointer<vtkActor> octreeActor =
vtkSmartPointer<vtkActor>::New();
octreeActor->SetMapper(octreeMapper);
octreeActor->GetProperty()->SetInterpolationToFlat();
octreeActor->GetProperty()->SetRepresentationToWireframe();
// A renderer and render window
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
// An interactor
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
// Add the actors to the scene
renderer->AddActor(pointsActor);
renderer->AddActor(octreeActor);
// Render an image (lights and cameras are created automatically)
renderWindow->Render();
vtkSmartPointer<vtkSliderRepresentation2D> sliderRep =
vtkSmartPointer<vtkSliderRepresentation2D>::New();
sliderRep->SetMinimumValue(0);
sliderRep->SetMaximumValue(kdTree->GetLevel());
sliderRep->SetValue(0);
sliderRep->SetTitleText("Level");
sliderRep->GetPoint1Coordinate()->SetCoordinateSystemToNormalizedDisplay();
sliderRep->GetPoint1Coordinate()->SetValue(.2, .2);
sliderRep->GetPoint2Coordinate()->SetCoordinateSystemToNormalizedDisplay();
sliderRep->GetPoint2Coordinate()->SetValue(.8, .2);
sliderRep->SetSliderLength(0.075);
sliderRep->SetSliderWidth(0.05);
sliderRep->SetEndCapLength(0.05);
vtkSmartPointer<vtkSliderWidget> sliderWidget =
vtkSmartPointer<vtkSliderWidget>::New();
sliderWidget->SetInteractor(renderWindowInteractor);
sliderWidget->SetRepresentation(sliderRep);
sliderWidget->SetAnimationModeToAnimate();
sliderWidget->EnabledOn();
vtkSmartPointer<vtkSliderCallback> callback =
vtkSmartPointer<vtkSliderCallback>::New();
callback->KdTree = kdTree;
callback->PolyData = polydata;
callback->Renderer = renderer;
sliderWidget->AddObserver(vtkCommand::InteractionEvent,callback);
renderWindowInteractor->Initialize();
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(VisualizeKDTree)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(VisualizeKDTree MACOSX_BUNDLE VisualizeKDTree.cxx)
target_link_libraries(VisualizeKDTree ${VTK_LIBRARIES})
Download and Build VisualizeKDTree
Click here to download VisualizeKDTree and its CMakeLists.txt file. Once the tarball VisualizeKDTree.tar has been downloaded and extracted,
cd VisualizeKDTree/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:
./VisualizeKDTree
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.