Examples/SpatialObjects/LineSpatialObject.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::LineSpatialObject}
//
// \doxygen{LineSpatialObject} defines a line in an n-dimensional space.  A
// line is defined as a list of points which compose the line, i.e a
// polyline. We begin the example by including the appropriate header files.
//
// Software Guide : EndLatex
 
// Software Guide : BeginCodeSnippet
#include "itkLineSpatialObject.h"
// Software Guide : EndCodeSnippet
 
int
main(int, char *[])
{
  // Software Guide : BeginLatex
  //
  // \code{LineSpatialObject} is templated over the dimension of the space.
  // A \code{LineSpatialObject} contains a list of
  // \code{LineSpatialObjectPoint}s. A \code{LineSpatialObjectPoint} has a
  // position, $n-1$ normals and a color. Each normal is expressed as a
  // \doxygen{CovariantVector} of size N.
  //
  // First, we define some type definitions and we create our line.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  using LineType = itk::LineSpatialObject<3>;
  using LinePointer = LineType::Pointer;
  using LinePointType = LineType::LinePointType;
 
  using PointType = LineType::PointType;
  using CovariantVectorType = LineType::CovariantVectorType;
 
  LinePointer Line = LineType::New();
  // Software Guide : EndCodeSnippet
 
  // Software Guide : BeginLatex
  //
  // We create a point list 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 red.
  //
  // The two normals are set using the \code{SetNormalInObjectSpace()}
  // function; the first argument is the normal itself and the second argument
  // is the index of the normal.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  LineType::LinePointListType list;
 
  for (unsigned int i = 0; i < 3; ++i)
  {
    LinePointType p;
    PointType     pnt;
    pnt[0] = i;
    pnt[1] = i + 1;
    pnt[2] = i + 2;
    p.SetPositionInObjectSpace(pnt);
    p.SetColor(1, 0, 0, 1);
 
    CovariantVectorType normal1;
    CovariantVectorType normal2;
    for (unsigned int j = 0; j < 3; ++j)
    {
      normal1[j] = j;
      normal2[j] = j * 2;
    }
 
    p.SetNormalInObjectSpace(normal1, 0);
    p.SetNormalInObjectSpace(normal2, 1);
    list.push_back(p);
  }
  // Software Guide : EndCodeSnippet
 
  // Software Guide : BeginLatex
  //
  // Next, we set the name of the object using \code{SetName()}. We also set
  // its identification number with \code{SetId()} and we set the list of
  // points previously created.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  Line->GetProperty().SetName("Line1");
  Line->SetId(1);
  Line->SetPoints(list);
  Line->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
  LineType::LinePointListType pointList = Line->GetPoints();
  std::cout << "Number of points representing the line: ";
  std::cout << pointList.size() << std::endl;
  // Software Guide : EndCodeSnippet
 
 
  // Software Guide : BeginLatex
  //
  // Then we can access the points using standard STL iterators.  The
  // \code{GetPositionInObjectSpace()} and \code{GetColor()} functions return
  // respectively the position
  // and the color of the point. Using the
  // \code{GetNormalInObjectSpace(unsigned int)} function we
  // can access each normal.
  //
  // Software Guide : EndLatex
 
  // Software Guide : BeginCodeSnippet
  LineType::LinePointListType::const_iterator it = Line->GetPoints().begin();
  while (it != Line->GetPoints().end())
  {
    std::cout << "Position = " << (*it).GetPositionInObjectSpace()
              << std::endl;
    std::cout << "Color = " << (*it).GetColor() << std::endl;
    std::cout << "First normal = " << (*it).GetNormalInObjectSpace(0)
              << std::endl;
    std::cout << "Second normal = " << (*it).GetNormalInObjectSpace(1)
              << std::endl;
    std::cout << std::endl;
    ++it;
  }
  // Software Guide : EndCodeSnippet
 
  return EXIT_SUCCESS;
}