ITK  5.0.0
Insight Segmentation and Registration Toolkit
Examples/SpatialObjects/MeshSpatialObject.cxx
/*=========================================================================
*
* Copyright Insight Software Consortium
*
* 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
*
* http://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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*=========================================================================*/
// Software Guide : BeginLatex
//
// \index{itk::MeshSpatialObject}
//
// A \doxygen{MeshSpatialObject} contains a pointer to an \doxygen{Mesh} but adds the
// notion of spatial transformations and parent-child hierarchy.
// This example shows how to create an \doxygen{MeshSpatialObject},
// use it to form a binary image, and write the mesh to disk.
//
// Let's begin by including the appropriate header file.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
// Software Guide : EndCodeSnippet
int main(int, char * [] )
{
// Software Guide : BeginLatex
//
// The MeshSpatialObject wraps an \doxygen{Mesh}, therefore we first
// create a mesh.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using CellTraits = MeshType::CellTraits;
using CellInterfaceType = itk::CellInterface< float, CellTraits >;
using CellType = MeshType::CellType;
using CellAutoPointer = CellType::CellAutoPointer;
// Software Guide : EndCodeSnippet
// Software Guide : BeginCodeSnippet
MeshType::Pointer myMesh = MeshType::New();
MeshType::CoordRepType testPointCoords[4][3]
= { {0,0,0}, {9,0,0}, {9,9,0}, {0,0,9} };
MeshType::PointIdentifier tetraPoints[4] = {0,1,2,4};
int i;
for(i=0; i < 4; ++i)
{
myMesh->SetPoint(i, PointType(testPointCoords[i]));
}
myMesh->SetCellsAllocationMethod(
MeshType::CellsAllocatedDynamicallyCellByCell );
CellAutoPointer testCell1;
testCell1.TakeOwnership( new TetraCellType );
testCell1->SetPointIds(tetraPoints);
// Software Guide : EndCodeSnippet
// Software Guide : BeginCodeSnippet
myMesh->SetCell(0, testCell1 );
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// We then create a MeshSpatialObject which is templated over the type of mesh
// previously defined...
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using MeshSpatialObjectType = itk::MeshSpatialObject< MeshType >;
MeshSpatialObjectType::Pointer myMeshSpatialObject
= MeshSpatialObjectType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// ... and pass the Mesh pointer to the MeshSpatialObject
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
myMeshSpatialObject->SetMesh(myMesh);
myMeshSpatialObject->Update();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The actual pointer to the passed mesh can be retrieved using the
// \code{GetMesh()} function, just like any other SpatialObjects.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
myMeshSpatialObject->GetMesh();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The \code{GetBoundingBox()}, \code{ValueAt()}, \code{IsInside()}
// functions can be used to access important information.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
std::cout << "Mesh bounds : "
<< myMeshSpatialObject->GetMyBoundingBoxInWorldSpace()->GetBounds()
<< std::endl;
myPhysicalPoint.Fill(1);
std::cout << "Is my physical point inside? : "
<< myMeshSpatialObject->IsInsideInWorldSpace(myPhysicalPoint) << std::endl;
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Now that we have defined the MeshSpatialObject, we can save the actual mesh
// using the \doxygen{SpatialObjectWriter}. In order to do so,
// we need to specify the type of Mesh we are writing.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
WriterType::Pointer writer = WriterType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Then we set the mesh spatial object and the name of the file and call the
// the \code{Update()} function.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
writer->SetInput(myMeshSpatialObject);
writer->SetFileName("myMesh.meta");
writer->Update();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Reading the saved mesh is done using the \doxygen{SpatialObjectReader}.
// Once again we need to specify the type of mesh we intend to read.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
ReaderType::Pointer reader = ReaderType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// We set the name of the file we want to read and call update
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
reader->SetFileName("myMesh.meta");
reader->Update();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Next, we show how to create a binary image of a MeshSpatialObject
// using the \doxygen{SpatialObjectToImageFilter}. The resulting image
// will have ones inside and zeros outside the mesh.
// First we define and instantiate the SpatialObjectToImageFilter.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using ImageType = itk::Image< unsigned char, 3 >;
using GroupType = itk::GroupSpatialObject< 3 >;
using SpatialObjectToImageFilterType =
SpatialObjectToImageFilterType::Pointer imageFilter =
SpatialObjectToImageFilterType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Then we pass the output of the reader, i.e the MeshSpatialObject, to the
// filter.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
imageFilter->SetInput( reader->GetGroup() );
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Finally we trigger the execution of the filter by calling the
// \code{Update()} method. Note that depending on the size of the mesh,
// the computation time can increase significantly.
// \index{itk::SpatialObjectToImageFilter!Update()}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
imageFilter->Update();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Then we can get the resulting binary image using the \code{GetOutput()} function.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
ImageType::Pointer myBinaryMeshImage = imageFilter->GetOutput();
// Software Guide : EndCodeSnippet
return EXIT_SUCCESS;
}