PointUtils.h

 
#pragma once
 
#if defined(PointUtils_RECURSES)
#error Recursive header files inclusion detected in PointUtils.h
#else // defined(PointUtils_RECURSES)
#define PointUtils_RECURSES
 
#if !defined PointUtils_h
#define PointUtils_h
 
// Inclusions
#include <vector>
#include "DGtal/base/Common.h"
 
namespace DGtal{
 template<typename TPointType>
 typename TPointType::Coordinate det( const TPointType& p, const TPointType& q ) {
  return p[ 0 ] * q[ 1 ] - p[ 1 ] * q[ 0 ];
 }
 
 template<typename TPointType>
 bool less( const TPointType& p, const TPointType& q ) {
  return ( p[ 0 ] * q[ 1 ] - p[ 1 ] * q[ 0 ] ) > 0;
 }
 
 
 
 template<typename TPointType>
 bool less( const TPointType& p, const TPointType& q );
 
 template<typename TPointType>
 std::vector< TPointType > nextNeighbors( TPointType p ) {
  std::vector< TPointType > V;
  TPointType zero( 0, 0 );
  TPointType p0( p[ 0 ]+1, p[ 1 ] );
  if ( less( p, p0 ) ) V.push_back( p0 );
  TPointType p1( p[ 0 ]+1, p[ 1 ]+1 );
  if ( less( p, p1 ) ) V.push_back( p1 );
  TPointType p2( p[ 0 ], p[ 1 ]+1 );
  if ( less( p, p2 ) ) V.push_back( p2 );
  TPointType p3( p[ 0 ]-1, p[ 1 ]+1 );
  if ( less( p, p3 ) ) V.push_back( p3 );
  TPointType p4( p[ 0 ]-1, p[ 1 ] );
  if ( less( p, p4 ) ) V.push_back( p4 );
  TPointType p5( p[ 0 ]-1, p[ 1 ]-1 );
  if ( less( p, p5 ) ) V.push_back( p5 );
  TPointType p6( p[ 0 ], p[ 1 ]-1 );
  if ( less( p, p6 ) ) V.push_back( p6 );
  TPointType p7( p[ 0 ]+1, p[ 1 ]-1 );
  if ( less( p, p7 ) ) V.push_back( p7 );
  return V;
 }
 
 template<typename TPointType>
 typename TPointType::Coordinate distance2( TPointType p, TPointType q ) {
  typename TPointType::Coordinate d2 = (p[ 0 ] - q[ 0 ])*(p[ 0 ] - q[ 0 ])+(p[ 1 ] - q[ 1 ])*(p[ 1 ] - q[ 1 ]);
  return d2;
 }
 
 
 
 template<typename TPointType1,typename TPointType2>
  typename TPointType2::Coordinate distance2( TPointType1 p, TPointType2 q ) {
  typename TPointType2::Coordinate d2 = (p[ 0 ] - q[ 0 ])*(p[ 0 ] - q[ 0 ])+(p[ 1 ] - q[ 1 ])*(p[ 1 ] - q[ 1 ]);
  return d2;
 }
 
 
}
#endif //PointUtils
#undef PointUtils_RECURSES
#endif // else defined(PointUtils_RECURSES)