/**Describes the result of a snapping operation*/
struct QgsSnappingResult
{
%TypeHeaderCode
#include <qgssnapper.h>
%End
  
  /**The coordinates of the snapping result*/
  QgsPoint snappedVertex;
  /**The vertex index of snappedVertex 
   or -1 if no such vertex number (e.g. snap to segment)*/
  int snappedVertexNr;
  /**The layer coordinates of the vertex before snappedVertex*/
  QgsPoint beforeVertex;
  /**The index of the vertex before snappedVertex
   or -1 if no such vertex*/
  int beforeVertexNr;
  /**The layer coordinates of the vertex after snappedVertex*/
  QgsPoint afterVertex;
  /**The index of the vertex after snappedVertex
   or -1 if no such vertex*/
  int afterVertexNr;
  /**Index of the snapped geometry*/
  int snappedAtGeometry;
  /**Layer where the snap occured*/
  const QgsVectorLayer* layer;
};



/**A class that allows advanced snapping operations on a set of vector layers*/
class QgsSnapper
{
%TypeHeaderCode
#include <qgssnapper.h>
%End
  
public:
  /**Snap to vertex, to segment or both*/
  enum SnappingType
    {
      SnapToVertex,
      SnapToSegment,
      //snap to vertex and also to segment if no vertex is within the search tolerance
      SnapToVertexAndSegment
    };
  
  enum SnappingMode
    {
      /**Only one snapping result is retured*/
      SnapWithOneResult,
      /**Several snapping results which have the same position are returned. This is useful for topological
       editing*/
      SnapWithResultsForSamePosition,
      /**All results within the given layer tolerances are returned*/
      SnapWithResultsWithinTolerances
    };

    struct SnapLayer
    {
      /**The layer to which snapping is applied*/
      QgsVectorLayer* mLayer;
      /**The snapping tolerances for the layers, always in source coordinate systems of the layer*/
      double mTolerance;
      /**What snapping type to use (snap to segment or to vertex)*/
      QgsSnapper::SnappingType mSnapTo;
      /**What unit is used for tolerance*/
      QgsTolerance::UnitType mUnitType;
    };  
    
  QgsSnapper(QgsMapRenderer* mapRender);
  ~QgsSnapper();
  /**Does the snapping operation
   @param startPoint the start point for snapping (in pixel coordinates)
  @param snappingResult the list where the results are inserted (everything in map coordinate system)
  @return 0 in case of success*/
  int snapPoint(const QPoint& startPoint, QList<QgsSnappingResult>& snappingResult /Out/, const QList<QgsPoint>& excludeList);

  //setters
  void setSnapLayers( const QList<QgsSnapper::SnapLayer>& snapLayers );
  void setSnapMode(QgsSnapper::SnappingMode snapMode);

};