PointInsideObject
VTKExamples/Cxx/PolyData/PointInsideObject
Description¶
This example creates a cube at the origin with side 1. Then it checks if the points are inside the cube. There is one point inside, one in the border and one outside. The answer for the first one should be yes, and for the other two, no. Then render the cube and the points to see the result.
Code¶
PointInsideObject.cxx
#include <vtkVersion.h> #include <vtkPolyData.h> #include <vtkPointData.h> #include <vtkCubeSource.h> #include <vtkSmartPointer.h> #include <vtkSelectEnclosedPoints.h> #include <vtkIntArray.h> #include <vtkDataArray.h> #include <vtkVertexGlyphFilter.h> #include <vtkProperty.h> #include <vtkPolyDataMapper.h> #include <vtkActor.h> #include <vtkRenderWindow.h> #include <vtkRenderer.h> #include <vtkRenderWindowInteractor.h> #include <vtkVertexGlyphFilter.h> int main(int, char *argv[]) { //cube centered in origin, 1cm side. vtkSmartPointer<vtkCubeSource> cubeSource = vtkSmartPointer<vtkCubeSource>::New(); cubeSource->Update(); vtkPolyData* cube = cubeSource->GetOutput(); double testInside[3] = {0.0, 0.0, 0.0}; double testOutside[3] = {0.7, 0.0, 0.0}; double testBorderOutside[3] = {0.5, 0.0, 0.0}; vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New(); points->InsertNextPoint(testInside); points->InsertNextPoint(testOutside); points->InsertNextPoint(testBorderOutside); vtkSmartPointer<vtkPolyData> pointsPolydata = vtkSmartPointer<vtkPolyData>::New(); pointsPolydata->SetPoints(points); //Points inside test vtkSmartPointer<vtkSelectEnclosedPoints> selectEnclosedPoints = vtkSmartPointer<vtkSelectEnclosedPoints>::New(); #if VTK_MAJOR_VERSION <= 5 selectEnclosedPoints->SetInput(pointsPolydata); #else selectEnclosedPoints->SetInputData(pointsPolydata); #endif #if VTK_MAJOR_VERSION <= 5 selectEnclosedPoints->SetSurface(cube); #else selectEnclosedPoints->SetSurfaceData(cube); #endif selectEnclosedPoints->Update(); for(unsigned int i = 0; i < 2; i++) { std::cout << "Point " << i << ": " << selectEnclosedPoints->IsInside(i) << std::endl; } vtkDataArray* insideArray = vtkDataArray::SafeDownCast(selectEnclosedPoints->GetOutput()->GetPointData()->GetArray("SelectedPoints")); for(vtkIdType i = 0; i < insideArray->GetNumberOfTuples(); i++) { std::cout << i << " : " << insideArray->GetComponent(i,0) << std::endl; } //RENDERING PART //Cube mapper, actor vtkSmartPointer<vtkPolyDataMapper> cubeMapper = vtkSmartPointer<vtkPolyDataMapper>::New(); cubeMapper->SetInputConnection(cubeSource->GetOutputPort()); vtkSmartPointer<vtkActor> cubeActor = vtkSmartPointer<vtkActor>::New(); cubeActor->SetMapper(cubeMapper); cubeActor->GetProperty()->SetOpacity(0.5); //Points mapper, actor //First, apply vtkVertexGlyphFilter to make cells around points, vtk only render cells. vtkSmartPointer<vtkVertexGlyphFilter> vertexGlyphFilter = vtkSmartPointer<vtkVertexGlyphFilter>::New(); #if VTK_MAJOR_VERSION <= 5 vertexGlyphFilter->AddInput(pointsPolydata); #else vertexGlyphFilter->AddInputData(pointsPolydata); #endif vertexGlyphFilter->Update(); vtkSmartPointer<vtkPolyDataMapper> pointsMapper = vtkSmartPointer<vtkPolyDataMapper>::New(); pointsMapper->SetInputConnection(vertexGlyphFilter->GetOutputPort()); vtkSmartPointer<vtkActor> pointsActor = vtkSmartPointer<vtkActor>::New(); pointsActor->SetMapper(pointsMapper); pointsActor->GetProperty()->SetPointSize(5); pointsActor->GetProperty()->SetColor(0.0,0.0,1); //Create a renderer, render window, and interactor vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New(); vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->AddRenderer(renderer); vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); renderWindowInteractor->SetRenderWindow(renderWindow); // Add the actor to the scene renderer->AddActor(cubeActor); renderer->AddActor(pointsActor); renderer->SetBackground(.0, 1,.0); // Render and interact renderWindow->SetWindowName(argv[0]); renderWindow->Render(); renderWindowInteractor->Start(); return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(PointInsideObject) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(PointInsideObject MACOSX_BUNDLE PointInsideObject.cxx) target_link_libraries(PointInsideObject ${VTK_LIBRARIES})
Download and Build PointInsideObject¶
Danger
The generation of tar files has not been ported to the new VTKExamples. Some tarballs may be missing or out-of-date.
Click here to download PointInsideObject and its CMakeLists.txt file. Once the tarball PointInsideObject.tar has been downloaded and extracted,
cd PointInsideObject/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:
./PointInsideObject
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.