Examples/SpatialObjects/BlobSpatialObject.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.
 *
 *=========================================================================*/
 
// Software Guide : BeginLatex
//
// \index{itk::BlobSpatialObject}
//
// \doxygen{BlobSpatialObject} defines an n-dimensional blob.
// This class derives from \doxygen{itkPointBasedSpatialObject}.  A blob
// is defined as a list of points which compose the object.
//
// Let's start by including the appropriate header file.
//
// Software Guide : EndLatex
 
// Software Guide : BeginCodeSnippet
#include "itkBlobSpatialObject.h"
// Software Guide : EndCodeSnippet
 
// Software Guide : BeginLatex
//
// BlobSpatialObject is templated over the dimension of the space.
// A BlobSpatialObject contains a list of SpatialObjectPoints. Basically,
// a SpatialObjectPoint has a position and a color.
//
// Software Guide : EndLatex
 
// Software Guide : BeginCodeSnippet
#include "itkSpatialObjectPoint.h"
// Software Guide : EndCodeSnippet
 
int
main(int, char *[])
{
  // Software Guide : BeginLatex
  //
  // First we declare several standard type definitions.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  using BlobType = itk::BlobSpatialObject<3>;
  using BlobPointer = BlobType::Pointer;
  // Software Guide : BeginLatex
  //
  // Every Point-Based SpatialObject also provides type definitions for
  // their SpatialObject point type (e.g., \code{BlobPointType} for
  // \code{BlobSpatialObject}) as well as for a physical space point
  // (e.g., an \code{itk::Point}).
  //
  // Software Guide : EndLatex
  using BlobPointType = BlobType::BlobPointType;
  using PointType = BlobType::PointType;
  // Software Guide : EndCodeSnippet
 
  // Software Guide : BeginLatex
  //
  // Then, we create a list of points and we set the position of each point in
  // the local coordinate system using the \code{SetPositionInObjectSpace()}
  // method. We also set the color of each point to be red.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  BlobType::BlobPointListType list;
 
  for (unsigned int i = 0; i < 4; ++i)
  {
    BlobPointType p;
    PointType     pnt;
    pnt[0] = i;
    pnt[1] = i + 1;
    pnt[2] = i + 2;
    p.SetPositionInObjectSpace(pnt);
    p.SetRed(1);
    p.SetGreen(0);
    p.SetBlue(0);
    p.SetAlpha(1.0);
    list.push_back(p);
  }
  // Software Guide : EndCodeSnippet
 
  // Software Guide : BeginLatex
  //
  // Next, we create the blob and set its name using the \code{SetName()}
  // function. We also set its Identification number with \code{SetId()} and
  // we add the list of points previously created and call \code{Update()} so
  // that the object can update its transforms, bounding boxes, and other
  // cached convenience member variables.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  const BlobPointer blob = BlobType::New();
  blob->GetProperty().SetName("My Blob");
  blob->SetId(1);
  blob->SetPoints(list);
  blob->Update();
  // Software Guide : EndCodeSnippet
 
  // Software Guide : BeginLatex
  //
  // The \code{GetPoints()} method returns a reference to the internal list of
  // points of the object.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  const BlobType::BlobPointListType pointList = blob->GetPoints();
  std::cout << "The blob contains " << pointList.size();
  std::cout << " points" << std::endl;
  // Software Guide : EndCodeSnippet
 
 
  // Software Guide : BeginLatex
  //
  // Then we can access the points using standard STL iterators and
  // \code{GetPositionInWorldSpace()} and \code{GetColor()} functions return
  // respectively the position and the color of the point.
  //
  // \code{GetPositionInWorldSpace()} applies the
  // \code{ObjectToParentTransform}s of all of the parent objects to this
  // point.   Since this object has no parents and since this object's
  // \code{ObjectToParentTransform} is the identify transform (by default),
  // these world space positions are the same as the object space positions
  // that were set.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  BlobType::BlobPointListType::const_iterator it = blob->GetPoints().begin();
  while (it != blob->GetPoints().end())
  {
    std::cout << "Position = " << (*it).GetPositionInWorldSpace()
              << std::endl;
    std::cout << "Color = " << (*it).GetColor() << std::endl;
    ++it;
  }
  // Software Guide : EndCodeSnippet
 
  return EXIT_SUCCESS;
}