ColorIsosurface
VTKExamples/Cxx/VisualizationAlgorithms/ColorIsosurface
Description¶
This example shows how to color an isosurface with other data. Basically an isosurface is generated, and a data array is selected and used by the mapper to color the surface.
Code¶
ColorIsosurface.cxx
// This example shows how to color an isosurface with other // data. Basically an isosurface is generated, and a data array is // selected and used by the mapper to color the surface. #include <vtkSmartPointer.h> #include <vtkMultiBlockPLOT3DReader.h> #include <vtkMultiBlockDataSet.h> #include <vtkContourFilter.h> #include <vtkPolyDataNormals.h> #include <vtkPolyDataMapper.h> #include <vtkLODActor.h> #include <vtkCamera.h> #include <vtkStructuredGridOutlineFilter.h> #include <vtkPolyDataMapper.h> #include <vtkActor.h> #include <vtkRenderer.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkNamedColors.h> int main (int argc, char *argv[]) { if (argc < 3) { std::cout << "Usage: " << argv[0] << " combxyz.bin combq.bin" << std::endl; return EXIT_FAILURE; } // Read some data. The important thing here is to read a function as a // data array as well as the scalar and vector. (here function 153 is // named "Velocity Magnitude").Later this data array will be used to // color the isosurface. vtkSmartPointer<vtkMultiBlockPLOT3DReader> pl3d = vtkSmartPointer<vtkMultiBlockPLOT3DReader>::New(); pl3d->SetXYZFileName(argv[1]); pl3d->SetQFileName(argv[2]); pl3d->SetScalarFunctionNumber(100); pl3d->SetVectorFunctionNumber(202); pl3d->AddFunction(153); pl3d->Update(); // The contour filter uses the labeled scalar (function number 100 // above to generate the contour surface; all other data is // interpolated during the contouring process. vtkSmartPointer<vtkContourFilter> iso = vtkSmartPointer<vtkContourFilter>::New(); iso->SetInputData(pl3d->GetOutput()->GetBlock(0)); iso->SetValue(0, .24); vtkSmartPointer<vtkPolyDataNormals> normals = vtkSmartPointer<vtkPolyDataNormals>::New(); normals->SetInputConnection(iso->GetOutputPort()); normals->SetFeatureAngle(45); // We indicate to the mapper to use the velcoity magnitude, which is a // vtkDataArray that makes up part of the point attribute data. vtkSmartPointer<vtkPolyDataMapper> isoMapper = vtkSmartPointer<vtkPolyDataMapper>::New(); isoMapper->SetInputConnection(normals->GetOutputPort()); isoMapper->ScalarVisibilityOn(); isoMapper->SetScalarRange(0, 1500); isoMapper->SetScalarModeToUsePointFieldData(); isoMapper->ColorByArrayComponent("VelocityMagnitude", 0); vtkSmartPointer<vtkLODActor> isoActor = vtkSmartPointer<vtkLODActor>::New(); isoActor->SetMapper(isoMapper); isoActor->SetNumberOfCloudPoints(1000); vtkSmartPointer<vtkStructuredGridOutlineFilter> outline = vtkSmartPointer<vtkStructuredGridOutlineFilter>::New(); outline->SetInputData(pl3d->GetOutput()->GetBlock(0)); vtkSmartPointer<vtkPolyDataMapper> outlineMapper = vtkSmartPointer<vtkPolyDataMapper>::New(); outlineMapper->SetInputConnection(outline->GetOutputPort()); vtkSmartPointer<vtkActor> outlineActor = vtkSmartPointer<vtkActor>::New(); outlineActor->SetMapper(outlineMapper); // Create the usual rendering stuff. vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New(); vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->AddRenderer(renderer); vtkSmartPointer<vtkRenderWindowInteractor> interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); interactor->SetRenderWindow(renderWindow); vtkSmartPointer<vtkNamedColors> colors = vtkSmartPointer<vtkNamedColors>::New(); // Add the actors to the renderer, set the background and size renderer->AddActor(outlineActor); renderer->AddActor(isoActor); renderer->SetBackground(colors->GetColor3d("SlateGray").GetData()); renderWindow->SetSize(640, 480); // Pick a good view vtkCamera *cam1 = renderer->GetActiveCamera(); cam1->SetClippingRange(3.95297, 50); cam1->SetFocalPoint(9.71821, 0.458166, 29.3999); cam1->SetPosition(2.7439, -37.3196, 38.7167); cam1->SetViewUp(-0.16123, 0.264271, 0.950876); interactor->Initialize(); renderWindow->Render(); interactor->Start(); return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR) project(ColorIsosurface) find_package(VTK COMPONENTS vtkCommonColor vtkCommonCore vtkCommonDataModel vtkFiltersCore vtkIOParallel vtkInteractionStyle vtkRenderingCore vtkRenderingFreeType vtkRenderingLOD vtkRenderingOpenGL2 QUIET) if (NOT VTK_FOUND) message("Skipping ColorIsosurface: ${VTK_NOT_FOUND_MESSAGE}") return () endif() message (STATUS "VTK_VERSION: ${VTK_VERSION}") if (VTK_VERSION VERSION_LESS "8.90.0") # old system include(${VTK_USE_FILE}) add_executable(ColorIsosurface MACOSX_BUNDLE ColorIsosurface.cxx ) target_link_libraries(ColorIsosurface PRIVATE ${VTK_LIBRARIES}) else () # include all components add_executable(ColorIsosurface MACOSX_BUNDLE ColorIsosurface.cxx ) target_link_libraries(ColorIsosurface PRIVATE ${VTK_LIBRARIES}) # vtk_module_autoinit is needed vtk_module_autoinit( TARGETS ColorIsosurface MODULES ${VTK_LIBRARIES} ) endif ()
Download and Build ColorIsosurface¶
Click here to download ColorIsosurface and its CMakeLists.txt file. Once the tarball ColorIsosurface.tar has been downloaded and extracted,
cd ColorIsosurface/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:
./ColorIsosurface
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.