GenericClip
VTKExamples/Cxx/Filtering/GenericClip
Description
'''NOTE:''' This example requires vtk 6.0 or greater.
Code
GenericClip.cxx
#include <vtkActor.h>
#include <vtkBridgeDataSet.h> // Must build VTK with BUILD_TESTING=ON
#include <vtkCellData.h>
#include <vtkContourFilter.h>
#include <vtkDataSetMapper.h>
#include <vtkDelaunay3D.h>
#include <vtkElevationFilter.h>
#include <vtkGenericClip.h>
#include <vtkImageData.h>
#include <vtkImplicitDataSet.h>
#include <vtkIdFilter.h>
#include <vtkIdTypeArray.h>
#include <vtkSphereSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkSampleFunction.h>
#include <vtkSmartPointer.h>
#include <vtkPlane.h>
#include <vtkUnstructuredGrid.h>
int main(int, char*[])
{
// If we try to use a PointSource with vtkBridgeDataSet, an error is produced:
// vtkBridgeCell.cxx:141: virtual int vtkBridgeCell::GetType(): Assertion `"check: impossible case" && 0' failed.
// There does not seem to be a case to handle VTK_VERTEX (which is what is produced by PointSource) in vtkBridgeDataSet.
// vtkSmartPointer<vtkPointSource> pointSource =
// vtkSmartPointer<vtkPointSource>::New();
// pointSource->SetNumberOfPoints(100);
// pointSource->SetRadius(1.0);
// pointSource->Update();
vtkSmartPointer<vtkSphereSource> sphereSource =
vtkSmartPointer<vtkSphereSource>::New();
sphereSource->SetRadius(5);
sphereSource->SetThetaResolution(10);
sphereSource->SetPhiResolution(10);
sphereSource->Update();
// Add ids to the points and cells of the sphere
vtkSmartPointer<vtkIdFilter> idFilter =
vtkSmartPointer<vtkIdFilter>::New();
idFilter->SetInputConnection(sphereSource->GetOutputPort());
idFilter->Update();
// Create a plane to clip with
vtkSmartPointer<vtkPlane> plane = vtkSmartPointer<vtkPlane>::New();
plane->SetOrigin(0, 0, 0);
plane->SetNormal(1, 1, 1);
// Convert the DataSet to a GenericDataSet
vtkSmartPointer<vtkBridgeDataSet> bridgeDataSet = vtkSmartPointer<vtkBridgeDataSet>::New();
bridgeDataSet->SetDataSet(idFilter->GetOutput());
vtkSmartPointer<vtkGenericClip> clipper =
vtkSmartPointer<vtkGenericClip>::New();
clipper->SetClipFunction(plane);
clipper->SetInputData(bridgeDataSet);
clipper->Update();
// Get the clipped cell ids
vtkUnstructuredGrid* clipped = clipper->GetOutput();
vtkIdTypeArray* originalIds = vtkIdTypeArray::SafeDownCast(clipped->GetCellData()->GetArray("vtkIdFilter_Ids"));
for(vtkIdType i = 0; i < originalIds->GetNumberOfTuples(); i++)
{
std::cout << "new id " << i << ", original id " << originalIds->GetValue(i) << std::endl;
}
// Create a mapper and actor for clipped points
vtkSmartPointer<vtkDataSetMapper> mapper =
vtkSmartPointer<vtkDataSetMapper>::New();
mapper->SetInputConnection(clipper->GetOutputPort());
vtkSmartPointer<vtkActor> actor =
vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
// Create a mapper and actor for clipping function
vtkSmartPointer<vtkSampleFunction> sample =
vtkSmartPointer<vtkSampleFunction>::New();
sample->SetSampleDimensions(20,20,20);
sample->SetImplicitFunction(plane);
double value = 10.0;
double xmin = -value, xmax = value, ymin = -value, ymax = value, zmin = -value, zmax = value;
sample->SetModelBounds(xmin, xmax, ymin, ymax, zmin, zmax);
// Create the 0 isosurface
vtkSmartPointer<vtkContourFilter> contours =
vtkSmartPointer<vtkContourFilter>::New();
contours->SetInputConnection(sample->GetOutputPort());
contours->GenerateValues(1, 1, 1);
// Map the contours to graphical primitives
vtkSmartPointer<vtkPolyDataMapper> contourMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
contourMapper->SetInputConnection(contours->GetOutputPort());
contourMapper->SetScalarRange(0.0, 1.2);
// Create an actor for the sphere
vtkSmartPointer<vtkActor> sphereActor =
vtkSmartPointer<vtkActor>::New();
sphereActor->SetMapper(contourMapper);
// 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(actor);
renderer->AddActor(sphereActor);
renderer->SetBackground(1,1,1); // Background color white
// Render and interact
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(GenericClip)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(GenericClip MACOSX_BUNDLE GenericClip.cxx)
target_link_libraries(GenericClip ${VTK_LIBRARIES})
Download and Build GenericClip
Click here to download GenericClip and its CMakeLists.txt file. Once the tarball GenericClip.tar has been downloaded and extracted,
cd GenericClip/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:
./GenericClip
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.