gist.h

#ifndef __PGS_GIST_H__
#define __PGS_GIST_H__

#include "key.h"

/*!
  \file
  \brief GIST index declarations
*/


  /*!
    \brief returns the key of cached query
    \param pgstype \link PGS_DATA_TYPES type \endlink of query
    \param query pointer to current query
    \param key pointer to adress of cached key
    \return true if , cached query is equal to current query 
  */
  bool gq_cache_get_value ( unsigned pgstype , const void * query, int32 ** key );

  /*!  
    \brief copy current query , type and its key value to cache
    \param pgstype \link PGS_DATA_TYPES type \endlink of query
    \param query pointer to query
    \param key pointer to key
    \return nothing
  */
  void gq_cache_set_value ( unsigned pgstype , const void * query, const int32  * key );


  /*!
    Just a dummy. But PostgreSQL need this function
    to create a data type.
    \brief Input function of key value
    \return NULL datum and raises an error
    \note PostgreSQL function
  */
  Datum spherekey_in(PG_FUNCTION_ARGS);

  /*!
    Just a dummy. But PostgreSQL need this function
    to create a data type.
    \brief Output function of key value
    \return NULL datum and raises an error
    \note PostgreSQL function
  */
  Datum spherekey_out(PG_FUNCTION_ARGS);

  /*!
    This function does nothing.
    \brief GIST's decompress method 
    \return the key datum
    \note PostgreSQL function
  */
  Datum g_spherekey_decompress(PG_FUNCTION_ARGS);

  /*!
    Creates the key value from spherical circle.
    \brief GIST's compress method for circle
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_scircle_compress(PG_FUNCTION_ARGS);

  /*!
    Creates the key value from spherical point.
    \brief GIST's compress method for point
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_spoint_compress(PG_FUNCTION_ARGS);

  /*!
    Creates the key value from spherical line.
    \brief GIST's compress method for line
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_sline_compress(PG_FUNCTION_ARGS);

  /*!
    Creates the key value from spherical path.
    \brief GIST's compress method for path
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_spath_compress(PG_FUNCTION_ARGS);

  /*!
    Creates the key value from spherical polygon.
    \brief GIST's compress method for polygon
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_spoly_compress(PG_FUNCTION_ARGS);


  /*!
    Creates the key value from spherical ellipse.
    \brief GIST's compress method for ellipse
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_sellipse_compress(PG_FUNCTION_ARGS);

  /*!
    Creates the key value from spherical box.
    \brief GIST's compress method for box
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_sbox_compress(PG_FUNCTION_ARGS);


  /*!
    The GiST Union method for boxes.
    Returns the minimal bounding box that encloses all the entries in entryvec.
    \brief Unions two GIST entries.
    \return GIST entry datum
    \note PostgreSQL function
  */
  Datum g_spherekey_union (PG_FUNCTION_ARGS);


  /*!
    \brief GIST's equality method
    \return bool datum, true if equal
    \note PostgreSQL function
  */
  Datum g_spherekey_same(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's consistence method for point
    \return bool datum, true if consistent
    \note PostgreSQL function
  */
  Datum g_spoint_consistent(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's consistence method for circle
    \return bool datum, true if consistent
    \note PostgreSQL function
  */
  Datum g_scircle_consistent(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's consistence method for line
    \return bool datum, true if consistent
    \note PostgreSQL function
  */
  Datum g_sline_consistent(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's consistence method for path
    \return bool datum, true if consistent
    \note PostgreSQL function
  */
  Datum g_spath_consistent(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's consistence method for polygon
    \return bool datum, true if consistent
    \note PostgreSQL function
  */
  Datum g_spoly_consistent(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's consistence method for ellipse
    \return bool datum, true if consistent
    \note PostgreSQL function
  */
  Datum g_sellipse_consistent(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's consistence method for box
    \return bool datum, true if consistent
    \note PostgreSQL function
  */
  Datum g_sbox_consistent(PG_FUNCTION_ARGS);

  /*!
    \brief GIST's penalty method
    \return penalty value ( float datum )
    \note PostgreSQL function
  */
  Datum g_spherekey_penalty(PG_FUNCTION_ARGS);


  /*!
     This method is using the new linear algorithm for R-Trees.  
     See 'New Linear Node Splitting Algorithm for R-tree',
     C.H.Ang and T.C.Tan .
    \brief GIST's picksplit method
    \return GIST_SPLITVEC datum
    \note PostgreSQL function
  */
  Datum g_spherekey_picksplit(PG_FUNCTION_ARGS);


#endif