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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 (C) 2001-2006 Refractions Research Inc.
*
**********************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "liblwgeom_internal.h"
#include "lwgeom_log.h"
LWTIN* lwtin_add_lwtriangle(LWTIN *mobj, const LWTRIANGLE *obj)
{
return (LWTIN*)lwcollection_add_lwgeom((LWCOLLECTION*)mobj, (LWGEOM*)obj);
}
void lwtin_free(LWTIN *tin)
{
int i;
if ( ! tin ) return;
if ( tin->bbox )
lwfree(tin->bbox);
for ( i = 0; i < tin->ngeoms; i++ )
if ( tin->geoms && tin->geoms[i] )
lwtriangle_free(tin->geoms[i]);
if ( tin->geoms )
lwfree(tin->geoms);
lwfree(tin);
}
void printLWTIN(LWTIN *tin)
{
int i;
LWTRIANGLE *triangle;
if (tin->type != TINTYPE)
lwerror("printLWTIN called with something else than a TIN");
lwnotice("LWTIN {");
lwnotice(" ndims = %i", (int)FLAGS_NDIMS(tin->flags));
lwnotice(" SRID = %i", (int)tin->srid);
lwnotice(" ngeoms = %i", (int)tin->ngeoms);
for (i=0; i<tin->ngeoms; i++)
{
triangle = (LWTRIANGLE *) tin->geoms[i];
printPA(triangle->points);
}
lwnotice("}");
}
/*
* TODO rewrite all this stuff to be based on a truly topological model
*/
struct struct_tin_arcs
{
double ax, ay, az;
double bx, by, bz;
int cnt, face;
};
typedef struct struct_tin_arcs *tin_arcs;
/* We supposed that the geometry is valid
we could have wrong result if not */
int lwtin_is_closed(const LWTIN *tin)
{
int i, j, k;
int narcs, carc;
int found;
tin_arcs arcs;
POINT4D pa, pb;
LWTRIANGLE *patch;
/* If surface is not 3D, it's can't be closed */
if (!FLAGS_GET_Z(tin->flags)) return 0;
/* Max theorical arcs number if no one is shared ... */
narcs = 3 * tin->ngeoms;
arcs = lwalloc(sizeof(struct struct_tin_arcs) * narcs);
for (i=0, carc=0; i < tin->ngeoms ; i++)
{
patch = (LWTRIANGLE *) tin->geoms[i];
for (j=0; j < 3 ; j++)
{
getPoint4d_p(patch->points, j, &pa);
getPoint4d_p(patch->points, j+1, &pb);
/* Make sure to order the 'lower' point first */
if ( (pa.x > pb.x) ||
(pa.x == pb.x && pa.y > pb.y) ||
(pa.x == pb.x && pa.y == pb.y && pa.z > pb.z) )
{
pa = pb;
getPoint4d_p(patch->points, j, &pb);
}
for (found=0, k=0; k < carc ; k++)
{
if ( ( arcs[k].ax == pa.x && arcs[k].ay == pa.y &&
arcs[k].az == pa.z && arcs[k].bx == pb.x &&
arcs[k].by == pb.y && arcs[k].bz == pb.z &&
arcs[k].face != i) )
{
arcs[k].cnt++;
found = 1;
/* Look like an invalid TIN
anyway not a closed one */
if (arcs[k].cnt > 2)
{
lwfree(arcs);
return 0;
}
}
}
if (!found)
{
arcs[carc].cnt=1;
arcs[carc].face=i;
arcs[carc].ax = pa.x;
arcs[carc].ay = pa.y;
arcs[carc].az = pa.z;
arcs[carc].bx = pb.x;
arcs[carc].by = pb.y;
arcs[carc].bz = pb.z;
carc++;
/* Look like an invalid TIN
anyway not a closed one */
if (carc > narcs)
{
lwfree(arcs);
return 0;
}
}
}
}
/* A TIN is closed if each edge
is shared by exactly 2 faces */
for (k=0; k < carc ; k++)
{
if (arcs[k].cnt != 2)
{
lwfree(arcs);
return 0;
}
}
lwfree(arcs);
/* Invalid TIN case */
if (carc < tin->ngeoms) return 0;
return 1;
}
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