GreedyTerrainDecimation
VTKExamples/Cxx/PolyData/GreedyTerrainDecimation
Code¶
GreedyTerrainDecimation.cxx
#include <vtkVersion.h> #include <vtkPolyData.h> #include <vtkProperty.h> #include <vtkMath.h> #include <vtkSmartPointer.h> #include <vtkPolyDataMapper.h> #include <vtkActor.h> #include <vtkRenderWindow.h> #include <vtkRenderer.h> #include <vtkRenderWindowInteractor.h> #include <vtkImageData.h> #include <vtkGreedyTerrainDecimation.h> int main(int, char *[]) { // Create an image vtkSmartPointer<vtkImageData> image = vtkSmartPointer<vtkImageData>::New(); image->SetDimensions(3,3,1); #if VTK_MAJOR_VERSION <= 5 image->SetNumberOfScalarComponents(1); image->SetScalarTypeToUnsignedChar(); #else image->AllocateScalars(VTK_UNSIGNED_CHAR,1); #endif int dims[3]; image->GetDimensions(dims); for(int i = 0; i < dims[0]; i++) { for(int j = 0; j < dims[1]; j++) { unsigned char* pixel = static_cast<unsigned char*>(image->GetScalarPointer(i,j,0)); //pixel[0] = vtkMath::Round(vtkMath::Random(0, 255)); pixel[0] = vtkMath::Round(vtkMath::Random(0, 1)); } } vtkSmartPointer<vtkGreedyTerrainDecimation> decimation = vtkSmartPointer<vtkGreedyTerrainDecimation>::New(); #if VTK_MAJOR_VERSION <= 5 decimation->SetInputConnection(image->GetProducerPort()); #else decimation->SetInputData(image); #endif decimation->Update(); // Visualize vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New(); mapper->SetInputConnection(decimation->GetOutputPort()); vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New(); actor->SetMapper(mapper); actor->GetProperty()->SetInterpolationToFlat(); actor->GetProperty()->EdgeVisibilityOn(); actor->GetProperty()->SetEdgeColor(1,0,0); vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New(); vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->AddRenderer(renderer); vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); renderWindowInteractor->SetRenderWindow(renderWindow); renderer->AddActor(actor); renderer->SetBackground(1,1,1); // Background color white renderWindow->Render(); renderWindowInteractor->Start(); return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(GreedyTerrainDecimation) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(GreedyTerrainDecimation MACOSX_BUNDLE GreedyTerrainDecimation.cxx) target_link_libraries(GreedyTerrainDecimation ${VTK_LIBRARIES})
Download and Build GreedyTerrainDecimation¶
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 GreedyTerrainDecimation and its CMakeLists.txt file. Once the tarball GreedyTerrainDecimation.tar has been downloaded and extracted,
cd GreedyTerrainDecimation/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:
./GreedyTerrainDecimation
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.