lwgeom_geos_prepared.h

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/**********************************************************************
 *
 * PostGIS - Spatial Types for PostgreSQL
 * http://postgis.net
 *
 * PostGIS is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * PostGIS is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with PostGIS.  If not, see <http://www.gnu.org/licenses/>.
 *
 **********************************************************************
 *
 * Copyright 2008 Paul Ramsey <pramsey@cleverelephant.ca>
 *
 **********************************************************************/
 
#pragma once
 
#include "postgres.h"
#include "fmgr.h"
#include "miscadmin.h"
#include "utils/hsearch.h"
#include "utils/memutils.h"
#include "access/hash.h"
 
#include "lwgeom_pg.h"
#include "liblwgeom.h"
#include "lwgeom_geos.h"
#include "lwgeom_cache.h"
 
/*
 * Cache structure. The common components used across all
 * caches are in the GeomCache. That contains SHARED_GSERIALIZED
 * and the argnum that indicates which argument we are caching
 * prepared geometry for.
 * The argnum gives the number of function arguments we are caching.
 * Intersects requires that both arguments be checked for cacheability,
 * while Contains only requires that the containing argument be checked.
 * Both the Geometry and the PreparedGeometry have to be cached,
 * because the PreparedGeometry contains a reference to the geometry.
 */
typedef struct {
        GeomCache                   gcache;
        MemoryContext               context_statement;
        MemoryContext               context_callback;
        const GEOSPreparedGeometry* prepared_geom;
        const GEOSGeometry*         geom;
} PrepGeomCache;
 
 
/*
 * Get the current cache, given the input geometries.
 * Function will create cache if none exists, and prepare geometries in
 * cache if necessary, or pull an existing cache if possible.
 *
 * If you are only caching one argument (e.g., in contains) supply 0 as the
 * value for pg_geom2.
 */
PrepGeomCache *GetPrepGeomCache(FunctionCallInfo fcinfo, SHARED_GSERIALIZED *pg_geom1, SHARED_GSERIALIZED *pg_geom2);