ITK  6.0.0
Insight Toolkit
SphinxExamples/src/Core/Mesh/CalculateAreaAndVolumeOfSimplexMesh/Code.cxx
/*=========================================================================
*
* Copyright NumFOCUS
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
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#define _USE_MATH_DEFINES // needed for Visual Studio (before #include <cmath>)
#include <itkSimplexMesh.h>
using TMesh = itk::Mesh<float, 3>;
using TSimplex = itk::SimplexMesh<float, 3>;
int
main()
{
// Create a spherical mesh with known radius and resolution.
auto source = TSphere::New();
scale.Fill(5.0);
source->SetScale(scale);
source->SetResolution(5);
source->Update();
// Ensure that all cells of the mesh are triangles.
for (TMesh::CellsContainerIterator it = source->GetOutput()->GetCells()->Begin();
it != source->GetOutput()->GetCells()->End();
++it)
{
TMesh::CellAutoPointer cell;
source->GetOutput()->GetCell(it->Index(), cell);
if (3 != cell->GetNumberOfPoints())
{
std::cerr << "ERROR: All cells must be trianglar." << std::endl;
return EXIT_FAILURE;
}
}
// Convert the triangle mesh to a simplex mesh.
auto convert = TConvert::New();
convert->SetInput(source->GetOutput());
convert->Update();
// Calculate the volume and area of the simplex mesh.
auto volume = TVolume::New();
volume->SetSimplexMesh(convert->GetOutput());
volume->Compute();
// Compare with the volume and area of an ideal sphere.
std::cout << "Ideal Volume: " << 4.0 / 3.0 * M_PI * pow(5.0, 3) << std::endl;
std::cout << "Mesh Volume: " << volume->GetVolume() << std::endl;
std::cout << "Ideal Surface Area: " << 4.0 * M_PI * pow(5.0, 2) << std::endl;
std::cout << "Mesh Surface Area: " << volume->GetArea() << std::endl;
return EXIT_SUCCESS;
}
itk::RegularSphereMeshSource
Inputs are the center of the mesh, the scale (radius in each dimension) of the mesh and a resolution ...
Definition: itkRegularSphereMeshSource.h:41
itkRegularSphereMeshSource.h
itk::TriangleMeshToSimplexMeshFilter
This filter converts a triangle mesh into a 2-simplex mesh.
Definition: itkTriangleMeshToSimplexMeshFilter.h:45
itkTriangleMeshToSimplexMeshFilter.h
itk::GTest::TypedefsAndConstructors::Dimension2::VectorType
ImageBaseType::SpacingType VectorType
Definition: itkGTestTypedefsAndConstructors.h:53
itk::SimplexMesh
The class represents a 2-simplex mesh.
Definition: itkSimplexMesh.h:47
itkSimplexMeshVolumeCalculator.h
itk::SimplexMeshVolumeCalculator
Adapted from itkSimplexMeshToTriangleFilter to calculate the volume of a simplex mesh using the baryc...
Definition: itkSimplexMeshVolumeCalculator.h:54
itk::Mesh
Implements the N-dimensional mesh structure.
Definition: itkMesh.h:126
New
static Pointer New()
itkSimplexMesh.h
itk::FixedArray::Fill
void Fill(const ValueType &)