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

  Program:   Visualization Toolkit
  Module:    vtkPKdTree.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.

=========================================================================*/
/*----------------------------------------------------------------------------
 Copyright (c) Sandia Corporation
 See Copyright.txt or http://www.paraview.org/HTML/Copyright.html for details.
----------------------------------------------------------------------------*/

// .NAME vtkPKdTree - Build a k-d tree decomposition of a list of points.
//
// .SECTION Description
//      Build, in parallel, a k-d tree decomposition of one or more
//      vtkDataSets distributed across processors.  We assume each
//      process has read in one portion of a large distributed data set.
//      When done, each process has access to the k-d tree structure,
//      can obtain information about which process contains
//      data for each spatial region, and can depth sort the spatial
//      regions.
//
//      This class can also assign spatial regions to processors, based
//      on one of several region assignment schemes.  By default
//      a contiguous, convex region is assigned to each process.  Several
//      queries return information about how many and what cells I have
//      that lie in a region assigned to another process.
//
// .SECTION See Also
//      vtkKdTree

#ifndef vtkPKdTree_h
#define vtkPKdTree_h

#include "vtkFiltersParallelModule.h" // For export macro
#include "vtkKdTree.h"

class vtkMultiProcessController;
class vtkCommunicator;
class vtkSubGroup;
class vtkIntArray;
class vtkKdNode;

class VTKFILTERSPARALLEL_EXPORT vtkPKdTree : public vtkKdTree
{
public:
  vtkTypeMacro(vtkPKdTree, vtkKdTree);


  void PrintSelf(ostream& os, vtkIndent indent);
  void PrintTiming(ostream& os, vtkIndent indent);
  void PrintTables(ostream& os, vtkIndent indent);

  static vtkPKdTree *New();

  // Description:
  //   Build the spatial decomposition.  Call this explicitly
  //   after changing any parameters affecting the build of the
  //   tree.  It must be called by all processes in the parallel
  //   application, or it will hang.
  void BuildLocator();

  // Description:
  //   Get the total number of cells distributed across the data
  //   files read by all processes.  You must have called BuildLocator
  //   before calling this method.
  vtkIdType GetTotalNumberOfCells(){return this->TotalNumCells;}

  // Description:
  //   Create tables of counts of cells per process per region.
  //   These tables can be accessed with queries like
  //   "HasData", "GetProcessCellCountForRegion", and so on.
  //   You must have called BuildLocator() beforehand.  This
  //   method must be called by all processes or it will hang.
  //   Returns 1 on error, 0 when no error.
  int CreateProcessCellCountData();

  // Description:
  //   A convenience function which compiles the global
  //   bounds of the data arrays across processes.
  //   These bounds can be accessed with
  //   "GetCellArrayGlobalRange" and "GetPointArrayGlobalRange".
  //   This method must be called by all processes or it will hang.
  //   Returns 1 on error, 0 when no error.
  int CreateGlobalDataArrayBounds();

  // Description:
  //   Set/Get the communicator object
  void SetController(vtkMultiProcessController *c);
  vtkGetObjectMacro(Controller, vtkMultiProcessController);

  // Description:
  //   The PKdTree class can assign spatial regions to processors after
  //   building the k-d tree, using one of several partitioning criteria.
  //   These functions Set/Get whether this assignment is computed.
  //   The default is "Off", no assignment is computed.   If "On", and
  //   no assignment scheme is specified, contiguous assignment will be
  //   computed.  Specifying an assignment scheme (with AssignRegions*())
  //   automatically turns on RegionAssignment.
  vtkGetMacro(RegionAssignment, int);

  static const int NoRegionAssignment;
  static const int ContiguousAssignment;
  static const int UserDefinedAssignment;
  static const int RoundRobinAssignment;

  // Description:
  //   Assign spatial regions to processes via a user defined map.
  //   The user-supplied map is indexed by region ID, and provides a
  //   process ID for each region.
  int AssignRegions(int *map, int numRegions);

  // Description:
  //   Let the PKdTree class assign a process to each region in a
  //   round robin fashion.  If the k-d tree has not yet been
  //   built, the regions will be assigned after BuildLocator executes.
  int AssignRegionsRoundRobin();

  // Description:
  //    Let the PKdTree class assign a process to each region
  //    by assigning contiguous sets of spatial regions to each
  //    process.  The set of regions assigned to each process will
  //    always have a union that is a convex space (a box).
  //    If the k-d tree has not yet been built, the regions
  //    will be assigned after BuildLocator executes.
  int AssignRegionsContiguous();

  // Description:
  // Returns the region assignment map where index is the region and value is
  // the processes id for that region.
  const int* GetRegionAssignmentMap()
    { return this->RegionAssignmentMap; }

  // Description:
  /// Returns the number of regions in the region assignment map.
  vtkGetMacro(RegionAssignmentMapLength, int);

  // Description:
  //    Writes the list of region IDs assigned to the specified
  //    process.  Regions IDs start at 0 and increase by 1 from there.
  //    Returns the number of regions in the list.
  int GetRegionAssignmentList(int procId, vtkIntArray *list);

  // Description:
  //    The k-d tree spatial regions have been assigned to processes.
  //    Given a point on the boundary of one of the regions, this
  //    method creates a list of all processes whose region
  //    boundaries include that point.  This may be required when
  //    looking for processes that have cells adjacent to the cells
  //    of a given process.
  void GetAllProcessesBorderingOnPoint(float x, float y, float z,
                                       vtkIntArray *list);

  // Description:
  //    Returns the ID of the process assigned to the region.
  int GetProcessAssignedToRegion(int regionId);

  // Description:
  //   Returns 1 if the process has data for the given region,
  //   0 otherwise.
  int HasData(int processId, int regionId);

  // Description:
  //   Returns the number of cells the specified process has in the
  //   specified region.
  int GetProcessCellCountForRegion(int processId, int regionId);

  // Description:
  //   Returns the total number of processes that have data
  //   falling within this spatial region.
  int GetTotalProcessesInRegion(int regionId);

  // Description:
  //   Adds the list of processes having data for the given
  //   region to the supplied list, returns the number of
  //   processes added.
  int GetProcessListForRegion(int regionId, vtkIntArray *processes);

  // Description:
  //   Writes the number of cells each process has for the region
  //   to the supplied list of length len.  Returns the number of
  //   cell counts written.  The order of the cell counts corresponds
  //   to the order of process IDs in the process list returned by
  //   GetProcessListForRegion.
  int GetProcessesCellCountForRegion(int regionId, int *count, int len);

  // Description:
  //   Returns the total number of spatial regions that a given
  //   process has data for.
  int GetTotalRegionsForProcess(int processId);

  // Description:
  //   Adds the region IDs for which this process has data to
  //   the supplied vtkIntArray.  Retruns the number of regions.
  int GetRegionListForProcess(int processId, vtkIntArray *regions);

  // Description:
  //   Writes to the supplied integer array the number of cells this
  //   process has for each region.  Returns the number of
  //   cell counts written.  The order of the cell counts corresponds
  //   to the order of region IDs in the region list returned by
  //   GetRegionListForProcess.
  int GetRegionsCellCountForProcess(int ProcessId, int *count, int len);

  // Description:
  //   After regions have been assigned to processes, I may want to know
  //   which cells I have that are in the regions assigned to a particular
  //   process.
  //
  //   This method takes a process ID and two vtkIdLists.  It
  //   writes to the first list the IDs of the cells
  //   contained in the process' regions.  (That is, their cell
  //   centroid is contained in the region.)  To the second list it
  //   write the IDs of the cells which intersect the process' regions
  //   but whose cell centroid lies elsewhere.
  //
  //   The total number of cell IDs written to both lists is returned.
  //   Either list pointer passed in can be NULL, and it will be ignored.
  //   If there are multiple data sets, you must specify which data set
  //   you wish cell IDs for.
  //
  //   The caller should delete these two lists when done.  This method
  //   uses the cell lists created in vtkKdTree::CreateCellLists().
  //   If the cell lists for the process' regions do not exist, this
  //   method will first build the cell lists for all regions by calling
  //   CreateCellLists().  You must remember to DeleteCellLists() when
  //   done with all calls to this method, as cell lists can require a
  //   great deal of memory.
  vtkIdType GetCellListsForProcessRegions(int ProcessId, int set,
            vtkIdList *inRegionCells, vtkIdList *onBoundaryCells);
  vtkIdType GetCellListsForProcessRegions(int ProcessId, vtkDataSet *set,
            vtkIdList *inRegionCells, vtkIdList *onBoundaryCells);
  vtkIdType GetCellListsForProcessRegions(int ProcessId,
                                          vtkIdList *inRegionCells,
                                          vtkIdList *onBoundaryCells);

  // Description:
  // Return a list of all processes in order from front to back given a
  // vector direction of projection.  Use this to do visibility sorts
  // in parallel projection mode. `orderedList' will be resized to the number
  // of processes. The return value is the number of processes.
  // \pre orderedList_exists: orderedList!=0
  int ViewOrderAllProcessesInDirection(const double directionOfProjection[3],
                                       vtkIntArray *orderedList);

  // Description:
  // Return a list of all processes in order from front to back given a
  // camera position.  Use this to do visibility sorts in perspective
  // projection mode. `orderedList' will be resized to the number
  // of processes. The return value is the number of processes.
  // \pre orderedList_exists: orderedList!=0
  int ViewOrderAllProcessesFromPosition(const double cameraPosition[3],
                                        vtkIntArray *orderedList);

  // Description:
  //    An added feature of vtkPKdTree is that it will calculate the
  //    the global range of field arrays across all processes.  You
  //    call CreateGlobalDataArrayBounds() to do this calculation.
  //    Then the following methods return the ranges.
  //    Returns 1 on error, 0 otherwise.

  int GetCellArrayGlobalRange(const char *name, float range[2]);
  int GetPointArrayGlobalRange(const char *name, float range[2]);
  int GetCellArrayGlobalRange(const char *name, double range[2]);
  int GetPointArrayGlobalRange(const char *name, double range[2]);

  int GetCellArrayGlobalRange(int arrayIndex, double range[2]);
  int GetPointArrayGlobalRange(int arrayIndex, double range[2]);
  int GetCellArrayGlobalRange(int arrayIndex, float range[2]);
  int GetPointArrayGlobalRange(int arrayIndex, float range[2]);

protected:

  vtkPKdTree();
  ~vtkPKdTree();

  void SingleProcessBuildLocator();
  int MultiProcessBuildLocator(double *bounds);

private:

  int RegionAssignment;

  vtkMultiProcessController *Controller;

  vtkSubGroup *SubGroup;

  static char *StrDupWithNew(const char *s);

  int NumProcesses;
  int MyId;

  // basic tables - each region is the responsibility of one process, but
  //                one process may be assigned many regions

  int *RegionAssignmentMap;        // indexed by region ID
  int RegionAssignmentMapLength;
  int **ProcessAssignmentMap;      // indexed by process ID
  int *NumRegionsAssigned;         // indexed by process ID

  int UpdateRegionAssignment();

  // basic tables reflecting the data that was read from disk
  // by each process

  char *DataLocationMap;              // by process, by region

  int *NumProcessesInRegion;          // indexed by region ID
  int **ProcessList;                  // indexed by region ID

  int *NumRegionsInProcess;           // indexed by process ID
  int **RegionList;                   // indexed by process ID

  vtkIdType **CellCountList;                // indexed by region ID

  double *CellDataMin;           // global range for data arrays
  double *CellDataMax;
  double *PointDataMin;
  double *PointDataMax;
  char **CellDataName;
  char **PointDataName;
  int NumCellArrays;
  int NumPointArrays;

  // distribution of indices for select operation

  int BuildGlobalIndexLists(vtkIdType ncells);

  vtkIdType *StartVal;
  vtkIdType *EndVal;
  vtkIdType *NumCells;
  vtkIdType TotalNumCells;

  // local share of points to be partitioned, and local cache

  int WhoHas(int pos);
  int _whoHas(int L, int R, int pos);
  float *GetLocalVal(int pos);
  float *GetLocalValNext(int pos);
  void SetLocalVal(int pos, float *val);
  void ExchangeVals(int pos1, int pos2);
  void ExchangeLocalVals(int pos1, int pos2);

  float *PtArray;
  float *PtArray2;
  float *CurrentPtArray;
  float *NextPtArray;
  int PtArraySize;

  int *SelectBuffer;

  // Parallel build of k-d tree

  int AllCheckForFailure(int rc, const char *where, const char *how);
  void AllCheckParameters();

  // Description:
  // Return the global bounds over all processes.  Returns true
  // if successful and false otherwise.
  bool VolumeBounds(double*);
  int DivideRegion(vtkKdNode *kd, int L, int level, int tag);
  int BreadthFirstDivide(double *bounds);
  void enQueueNode(vtkKdNode *kd, int L, int level, int tag);

  int Select(int dim, int L, int R);
  void _select(int L, int R, int K, int dim);
  void DoTransfer(int from, int to, int fromIndex, int toIndex, int count);

  int *PartitionAboutMyValue(int L, int R, int K, int dim);
  int *PartitionAboutOtherValue(int L, int R, float T, int dim);
  int *PartitionSubArray(int L, int R, int K, int dim, int p1, int p2);

  int CompleteTree();
#ifdef YIELDS_INCONSISTENT_REGION_BOUNDARIES
  void RetrieveData(vtkKdNode *kd, int *buf);
#else
  void ReduceData(vtkKdNode *kd, int *sources);
  void BroadcastData(vtkKdNode *kd);
#endif

  float *DataBounds(int L, int K, int R);
  void GetLocalMinMax(int L, int R, int me, float *min, float *max);

  static int FillOutTree(vtkKdNode *kd, int level);
  static int ComputeDepth(vtkKdNode *kd);
  static void PackData(vtkKdNode *kd, double *data);
  static void UnpackData(vtkKdNode *kd, double *data);
  static void CheckFixRegionBoundaries(vtkKdNode *tree);

  // list management

  int AllocateDoubleBuffer();
  void FreeDoubleBuffer();
  void SwitchDoubleBuffer();
  int AllocateSelectBuffer();
  void FreeSelectBuffer();

  void InitializeGlobalIndexLists();
  int AllocateAndZeroGlobalIndexLists();
  void FreeGlobalIndexLists();
  void InitializeRegionAssignmentLists();
  int AllocateAndZeroRegionAssignmentLists();
  void FreeRegionAssignmentLists();
  void InitializeProcessDataLists();
  int AllocateAndZeroProcessDataLists();
  void FreeProcessDataLists();
  void InitializeFieldArrayMinMax();
  int AllocateAndZeroFieldArrayMinMax();
  void FreeFieldArrayMinMax();

  void ReleaseTables();

  // Assigning regions to processors

  void AddProcessRegions(int procId, vtkKdNode *kd);
  void BuildRegionListsForProcesses();

  // Gather process/region data totals

  int *CollectLocalRegionProcessData();
  int BuildRegionProcessTables();
  int BuildFieldArrayMinMax();
  void AddEntry(int *list, int len, int id);
#ifdef VTK_USE_64BIT_IDS
  void AddEntry(vtkIdType *list, int len, vtkIdType id);
#endif
  static int BinarySearch(vtkIdType *list, int len, vtkIdType which);

  static int FindNextLocalArrayIndex(const char *n, const char **names, int len, int start=0);

  vtkPKdTree(const vtkPKdTree&) VTK_DELETE_FUNCTION;
  void operator=(const vtkPKdTree&) VTK_DELETE_FUNCTION;
};

#endif
