SmoothDiscreteMarchingCubes
vtk-examples/Cxx/Modelling/SmoothDiscreteMarchingCubes
Description¶
Creates surfaces from labeled data. Volume data does not always contain samples of continuous data. A volume may contain discrete integer values, often the result of segmentation. This example smooths the discrete models generated by vtkDiscreteMarchingCubes with vtkWindowedSincPolyDataFilter.
Seealso
DiscreteMarchingCubes produces rough models.
Other languages
See (Python)
Question
If you have a question about this example, please use the VTK Discourse Forum
Code¶
SmoothDiscreteMarchingCubes.cxx
#include <vtkActor.h>
#include <vtkDiscreteMarchingCubes.h>
#include <vtkImageData.h>
#include <vtkImageMathematics.h>
#include <vtkImageThreshold.h>
#include <vtkLookupTable.h>
#include <vtkMinimalStandardRandomSequence.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSampleFunction.h>
#include <vtkSmartPointer.h>
#include <vtkSphere.h>
#include <vtkWindowedSincPolyDataFilter.h>
namespace {
vtkSmartPointer<vtkLookupTable> MakeColors(unsigned int n);
vtkSmartPointer<vtkImageData> MakeBlob(int n, double radius);
} // namespace
int main(int /* argc */, char* /* argv */[])
{
int n = 20;
double radius = 8;
vtkSmartPointer<vtkImageData> blob = MakeBlob(n, radius);
vtkNew<vtkDiscreteMarchingCubes> discrete;
discrete->SetInputData(blob);
discrete->GenerateValues(n, 1, n);
unsigned int smoothingIterations = 15;
double passBand = 0.001;
double featureAngle = 120.0;
vtkNew<vtkWindowedSincPolyDataFilter> smoother;
smoother->SetInputConnection(discrete->GetOutputPort());
smoother->SetNumberOfIterations(smoothingIterations);
smoother->BoundarySmoothingOff();
smoother->FeatureEdgeSmoothingOff();
smoother->SetFeatureAngle(featureAngle);
smoother->SetPassBand(passBand);
smoother->NonManifoldSmoothingOn();
smoother->NormalizeCoordinatesOn();
smoother->Update();
vtkSmartPointer<vtkLookupTable> lut = MakeColors(n);
vtkNew<vtkPolyDataMapper> mapper;
mapper->SetInputConnection(smoother->GetOutputPort());
mapper->SetLookupTable(lut);
mapper->SetScalarRange(0, lut->GetNumberOfColors());
// Create the RenderWindow, Renderer and both Actors
//
vtkNew<vtkRenderer> ren1;
vtkNew<vtkRenderWindow> renWin;
renWin->AddRenderer(ren1);
renWin->SetWindowName("SmoothDiscreteMarchingCubes");
vtkNew<vtkRenderWindowInteractor> iren;
iren->SetRenderWindow(renWin);
vtkNew<vtkActor> actor;
actor->SetMapper(mapper);
ren1->AddActor(actor);
vtkNew<vtkNamedColors> colors;
ren1->SetBackground(colors->GetColor3d("Burlywood").GetData());
renWin->Render();
iren->Start();
return EXIT_SUCCESS;
return EXIT_SUCCESS;
}
namespace {
vtkSmartPointer<vtkImageData> MakeBlob(int n, double radius)
{
vtkNew<vtkImageData> blobImage;
double maxR = 50 - 2.0 * radius;
vtkNew<vtkMinimalStandardRandomSequence> randomSequence;
randomSequence->SetSeed(5071);
for (int i = 0; i < n; ++i)
{
vtkNew<vtkSphere> sphere;
sphere->SetRadius(radius);
auto x = randomSequence->GetRangeValue(-maxR, maxR);
randomSequence->Next();
auto y = randomSequence->GetRangeValue(-maxR, maxR);
randomSequence->Next();
auto z = randomSequence->GetRangeValue(-maxR, maxR);
randomSequence->Next();
sphere->SetCenter(int(x), int(y), int(z));
vtkNew<vtkSampleFunction> sampler;
sampler->SetImplicitFunction(sphere);
sampler->SetOutputScalarTypeToFloat();
sampler->SetSampleDimensions(100, 100, 100);
sampler->SetModelBounds(-50, 50, -50, 50, -50, 50);
vtkNew<vtkImageThreshold> thres;
thres->SetInputConnection(sampler->GetOutputPort());
thres->ThresholdByLower(radius * radius);
thres->ReplaceInOn();
thres->ReplaceOutOn();
thres->SetInValue(i + 1);
thres->SetOutValue(0);
thres->Update();
if (i == 0)
{
blobImage->DeepCopy(thres->GetOutput());
}
vtkNew<vtkImageMathematics> maxValue;
maxValue->SetInputData(0, blobImage);
maxValue->SetInputData(1, thres->GetOutput());
maxValue->SetOperationToMax();
maxValue->Modified();
maxValue->Update();
blobImage->DeepCopy(maxValue->GetOutput());
}
return blobImage;
}
// Generate some random colors
vtkSmartPointer<vtkLookupTable> MakeColors(unsigned int n)
{
vtkNew<vtkLookupTable> lut;
lut->SetNumberOfColors(n);
lut->SetTableRange(0, n - 1);
lut->SetScaleToLinear();
lut->Build();
lut->SetTableValue(0, 0, 0, 0, 1);
vtkNew<vtkMinimalStandardRandomSequence> randomSequence;
randomSequence->SetSeed(5071);
for (int i = 1; i < static_cast<int>(n); ++i)
{
auto r = randomSequence->GetRangeValue(0.4, 1);
randomSequence->Next();
auto g = randomSequence->GetRangeValue(0.4, 1);
randomSequence->Next();
auto b = randomSequence->GetRangeValue(0.4, 1);
randomSequence->Next();
lut->SetTableValue(i, r, g, b, 1.0);
}
return lut;
}
} // namespace
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(SmoothDiscreteMarchingCubes)
find_package(VTK COMPONENTS
vtkCommonColor
vtkCommonCore
vtkCommonDataModel
vtkFiltersCore
vtkFiltersGeneral
vtkImagingCore
vtkImagingHybrid
vtkImagingMath
vtkInteractionStyle
vtkRenderingContextOpenGL2
vtkRenderingCore
vtkRenderingFreeType
vtkRenderingGL2PSOpenGL2
vtkRenderingOpenGL2
QUIET
)
if (NOT VTK_FOUND)
message("Skipping SmoothDiscreteMarchingCubes: ${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(SmoothDiscreteMarchingCubes MACOSX_BUNDLE SmoothDiscreteMarchingCubes.cxx )
target_link_libraries(SmoothDiscreteMarchingCubes PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(SmoothDiscreteMarchingCubes MACOSX_BUNDLE SmoothDiscreteMarchingCubes.cxx )
target_link_libraries(SmoothDiscreteMarchingCubes PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS SmoothDiscreteMarchingCubes
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build SmoothDiscreteMarchingCubes¶
Click here to download SmoothDiscreteMarchingCubes and its CMakeLists.txt file. Once the tarball SmoothDiscreteMarchingCubes.tar has been downloaded and extracted,
cd SmoothDiscreteMarchingCubes/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:
./SmoothDiscreteMarchingCubes
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.