/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkIncrementalPointLocator.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
/**
 * @class   vtkIncrementalPointLocator
 * @brief   Abstract class in support of both
 *  point location and point insertion.
 *
 *
 *  Compared to a static point locator for pure location functionalities
 *  through some search structure established from a fixed set of points,
 *  an incremental point locator allows for, in addition, point insertion
 *  capabilities, with the search structure maintaining a dynamically
 *  increasing number of points. There are two incremental point locators,
 *  i.e., vtkPointLocator and vtkIncrementalOctreePointLocator. As opposed
 *  to the uniform bin-based search structure (adopted in vtkPointLocator)
 *  with a fixed spatial resolution, an octree mechanism (employed in
 *  vtkIncrementalOctreePointlocator) resorts to a hierarchy of tree-like
 *  sub-division of the 3D data domain. Thus it enables data-aware multi-
 *  resolution and accordingly accelerated point location as well as point
 *  insertion, particularly when handling a radically imbalanced layout of
 *  points as not uncommon in datasets defined on adaptive meshes. In other
 *  words, vtkIncrementalOctreePointLocator is an octree-based accelerated
 *  implementation of all functionalities of vtkPointLocator.
 *
 * @sa
 *  vtkLocator, vtkIncrementalOctreePointLocator, vtkPointLocator,
 *  vtkMergePoints vtkStaticPointLocator
*/

#ifndef vtkIncrementalPointLocator_h
#define vtkIncrementalPointLocator_h

#include "vtkCommonDataModelModule.h" // For export macro
#include "vtkAbstractPointLocator.h"

class vtkPoints;
class vtkIdList;

class VTKCOMMONDATAMODEL_EXPORT vtkIncrementalPointLocator : public vtkAbstractPointLocator
{
public:

  vtkTypeMacro( vtkIncrementalPointLocator, vtkAbstractPointLocator );
  void PrintSelf( ostream & os, vtkIndent indent ) override;

  /**
   * Given a point x assumed to be covered by the search structure, return the
   * index of the closest point (already inserted to the search structure)
   * regardless of the associated minimum squared distance relative to the
   * squared insertion-tolerance distance. This method is used when performing
   * incremental point insertion. Note -1 indicates that no point is found.
   * InitPointInsertion() should have been called in advance.
   */
  virtual vtkIdType FindClosestInsertedPoint( const double x[3] ) = 0;

  // -------------------------------------------------------------------------
  // ---------------------------- Point  Location ----------------------------
  // ---- All virtual functions related to point location are declared by ----
  // --------------- the parent class  vtkAbstractPointLocator ---------------
  // -------------------------------------------------------------------------

  // -------------------------------------------------------------------------
  // ---------------------------- Point Insertion ----------------------------
  // -------------------------------------------------------------------------

  /**
   * Initialize the point insertion process. newPts is an object, storing 3D
   * point coordinates, to which incremental point insertion puts coordinates.
   * It is created and provided by an external VTK class. Argument bounds
   * represents the spatial bounding box, into which the points fall.
   */
  virtual int InitPointInsertion( vtkPoints * newPts, const double bounds[6] ) = 0;

  /**
   * Initialize the point insertion process. newPts is an object, storing 3D
   * point coordinates, to which incremental point insertion puts coordinates.
   * It is created and provided by an external VTK class. Argument bounds
   * represents the spatial bounding box, into which the points fall.
   */
  virtual int InitPointInsertion( vtkPoints * newPts, const double bounds[6],
                                  vtkIdType estSize ) = 0;

  /**
   * Determine whether or not a given point has been inserted. Return the id of
   * the already inserted point if true, else return -1. InitPointInsertion()
   * should have been called in advance.
   */
  virtual vtkIdType IsInsertedPoint( double x, double y, double z ) = 0;

  /**
   * Determine whether or not a given point has been inserted. Return the id of
   * the already inserted point if true, else return -1. InitPointInsertion()
   * should have been called in advance.
   */
  virtual vtkIdType IsInsertedPoint( const double x[3] ) = 0;

  /**
   * Insert a point unless there has been a duplciate in the search structure.
   * This method is not thread safe.
   */
  virtual int InsertUniquePoint( const double x[3], vtkIdType & ptId ) = 0;

  /**
   * Insert a given point with a specified point index ptId. InitPointInsertion()
   * should have been called prior to this function. Also, IsInsertedPoint()
   * should have been called in advance to ensure that the given point has not
   * been inserted unless point duplication is allowed.
   */
  virtual void InsertPoint( vtkIdType ptId, const double x[3] ) = 0;

  /**
   * Insert a given point and return the point index. InitPointInsertion()
   * should have been called prior to this function. Also, IsInsertedPoint()
   * should have been called in advance to ensure that the given point has not
   * been inserted unless point duplication is allowed.
   */
  virtual vtkIdType InsertNextPoint( const double x[3] ) = 0;

protected:
  vtkIncrementalPointLocator();
  ~vtkIncrementalPointLocator() override;

private:
  vtkIncrementalPointLocator( const vtkIncrementalPointLocator & ) = delete;
  void operator = ( const vtkIncrementalPointLocator & ) = delete;
};

#endif
