ColorIsosurface
VTKEx/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.
Question
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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
vtkvtkCommonColor
vtkvtkCommonCore
vtkvtkCommonDataModel
vtkvtkFiltersCore
vtkvtkIOParallel
vtkvtkInteractionStyle
vtkvtkRenderingContextOpenGL2
vtkvtkRenderingCore
vtkvtkRenderingFreeType
vtkvtkRenderingGL2PSOpenGL2
vtkvtkRenderingLOD
vtkvtkRenderingOpenGL2 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.