/*=========================================================================
 *
 *  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.
 *
 *=========================================================================*/
#ifndef __itkRegionBasedLevelSetFunctionData_hxx
#define __itkRegionBasedLevelSetFunctionData_hxx

#include "itkRegionBasedLevelSetFunctionData.h"

namespace itk
{
template< typename TInputImage, typename TFeatureImage >
RegionBasedLevelSetFunctionData< TInputImage, TFeatureImage >
::RegionBasedLevelSetFunctionData()
{
  m_WeightedNumberOfPixelsInsideLevelSet  = 0.;
  m_WeightedNumberOfPixelsOutsideLevelSet = 0.;

  m_HeavisideFunctionOfLevelSetImage = ITK_NULLPTR;
}

template< typename TInputImage, typename TFeatureImage >
void
RegionBasedLevelSetFunctionData< TInputImage, TFeatureImage >
::CreateHeavisideFunctionOfLevelSetImage(const InputImageType *image)
{
  const InputRegionType region = image->GetLargestPossibleRegion();

  this->m_HeavisideFunctionOfLevelSetImage = InputImageType::New();
  this->m_HeavisideFunctionOfLevelSetImage->CopyInformation(image);
  this->m_HeavisideFunctionOfLevelSetImage->SetRegions(region);
  this->m_HeavisideFunctionOfLevelSetImage->Allocate(true); // initialize
                                                                                   // buffer
                                                                                   // to zero

  const InputPointType origin = image->GetOrigin();

  this->m_HeavisideFunctionOfLevelSetImage->TransformPhysicalPointToIndex(origin, this->m_Start);

  for ( unsigned int i = 0; i < ImageDimension; i++ )
    {
    this->m_End[i] = this->m_Start[i] + static_cast< InputIndexValueType >( region.GetSize()[i] ) - 1;
    }
}

template< typename TInputImage, typename TFeatureImage >
typename RegionBasedLevelSetFunctionData< TInputImage, TFeatureImage >::InputIndexType
RegionBasedLevelSetFunctionData< TInputImage, TFeatureImage >
::GetIndex(const FeatureIndexType & featureIndex)
{
  InputIndexType index;

  for ( unsigned int i = 0; i < ImageDimension; i++ )
    {
    index[i] = featureIndex[i] - static_cast< InputIndexValueType >( this->m_Start[i] );
    }

  return index;
}

template< typename TInputImage, typename TFeatureImage >
typename RegionBasedLevelSetFunctionData< TInputImage, TFeatureImage >::FeatureIndexType
RegionBasedLevelSetFunctionData< TInputImage, TFeatureImage >
::GetFeatureIndex(const InputIndexType & inputIndex)
{
  FeatureIndexType index;

  for ( unsigned int i = 0; i < ImageDimension; i++ )
    {
    index[i] = inputIndex[i] + static_cast< InputIndexValueType >( this->m_Start[i] );
    }

  return index;
}
} //end namespace itk

#endif
