ITK  5.0.0
Insight Segmentation and Registration Toolkit
Examples/DataRepresentation/Mesh/RGBPointSet.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.
*
*=========================================================================*/
// Software Guide : BeginLatex
//
// The following example illustrates how a point set can be parameterized to
// manage a particular pixel type. In this case, pixels of RGB type are used.
// The first step is then to include the header files of the
// \doxygen{RGBPixel} and \doxygen{PointSet} classes.
//
// \index{itk::PointSet!RGBPixel}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
#include "itkRGBPixel.h"
#include "itkPointSet.h"
// Software Guide : EndCodeSnippet
int main(int, char *[])
{
// Software Guide : BeginLatex
//
// Then, the pixel type can be defined by selecting the type to be used to
// represent each one of the RGB components.
//
// \index{itk::RGBPixel!Instantiation}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using PixelType = itk::RGBPixel< float >;
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The newly defined pixel type is now used to instantiate the PointSet
// type and subsequently create a point set object.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using PointSetType = itk::PointSet< PixelType, 3 >;
PointSetType::Pointer pointSet = PointSetType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The following code generates a circle and assigns RGB values to
// the points. The components of the RGB values in this example are
// computed to represent the position of the points.
//
// \index{itk::PointSet!SetPoint()}
// \index{itk::PointSet!SetPointData()}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
PointSetType::PixelType pixel;
unsigned int pointId = 0;
constexpr double radius = 3.0;
for(unsigned int i=0; i<360; i++)
{
const double angle = i * itk::Math::pi / 180.0;
point[0] = radius * std::sin( angle );
point[1] = radius * std::cos( angle );
point[2] = 1.0;
pixel.SetRed( point[0] * 2.0 );
pixel.SetGreen( point[1] * 2.0 );
pixel.SetBlue( point[2] * 2.0 );
pointSet->SetPoint( pointId, point );
pointSet->SetPointData( pointId, pixel );
pointId++;
}
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// All the points on the PointSet are visited using the following code.
//
// \index{itk::PointSet!GetPoints()}
// \index{itk::PointSet!points iterator}
// \index{itk::PointSet!iterating points}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using PointIterator = PointSetType::PointsContainer::ConstIterator;
PointIterator pointIterator = pointSet->GetPoints()->Begin();
PointIterator pointEnd = pointSet->GetPoints()->End();
while( pointIterator != pointEnd )
{
point = pointIterator.Value();
std::cout << point << std::endl;
++pointIterator;
}
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Note that here the \code{ConstIterator} was used instead of the
// \code{Iterator} since the pixel values are not expected to be modified.
// ITK supports const-correctness at the API level.
//
// Software Guide : EndLatex
// Software Guide : BeginLatex
//
// All the pixel values on the PointSet are visited using the following code.
//
// \index{itk::PointSet!GetPointData()}
// \index{itk::PointSet!data iterator}
// \index{itk::PointSet!iterating point data}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using PointDataIterator = PointSetType::PointDataContainer::ConstIterator;
PointDataIterator pixelIterator = pointSet->GetPointData()->Begin();
PointDataIterator pixelEnd = pointSet->GetPointData()->End();
while( pixelIterator != pixelEnd )
{
pixel = pixelIterator.Value();
std::cout << pixel << std::endl;
++pixelIterator;
}
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Again, please note the use of the \code{ConstIterator} instead of the
// \code{Iterator}.
//
// \index{ConstIterator}
// \index{const-correctness}
//
// Software Guide : EndLatex
return EXIT_SUCCESS;
}