LWGEOM*
lwgeom_sharedpaths(const LWGEOM* geom1, const LWGEOM* geom2)
{
#if POSTGIS_GEOS_VERSION < 33
lwerror("The GEOS version this postgis binary "
"was compiled against (%d) doesn't support "
"'SharedPaths' function (3.3.0+ required)",
POSTGIS_GEOS_VERSION);
return NULL;
#else /* POSTGIS_GEOS_VERSION >= 33 */
GEOSGeometry *g1, *g2, *g3;
LWGEOM *out;
int is3d, srid;
srid = geom1->srid;
error_if_srid_mismatch(srid, (int)(geom2->srid));
is3d = (FLAGS_GET_Z(geom1->flags) || FLAGS_GET_Z(geom2->flags)) ;
initGEOS(lwnotice, lwgeom_geos_error);
g1 = (GEOSGeometry *)LWGEOM2GEOS(geom1);
if ( 0 == g1 ) /* exception thrown at construction */
{
lwerror("First argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = (GEOSGeometry *)LWGEOM2GEOS(geom2);
if ( 0 == g2 ) /* exception thrown at construction */
{
lwerror("Second argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
GEOSGeom_destroy(g1);
return NULL;
}
g3 = GEOSSharedPaths(g1,g2);
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
if (g3 == NULL)
{
lwerror("GEOSSharedPaths: %s", lwgeom_geos_errmsg);
return NULL;
}
GEOSSetSRID(g3, srid);
out = GEOS2LWGEOM(g3, is3d);
GEOSGeom_destroy(g3);
if (out == NULL)
{
lwerror("GEOS2LWGEOM threw an error");
return NULL;
}
return out;
#endif /* POSTGIS_GEOS_VERSION >= 33 */
}
/* May return LWPOINT or LWMPOINT */
static LWGEOM*
lwgeom_extract_unique_endpoints(const LWGEOM* lwg)
{
LWGEOM* ret;
GEOSGeometry *gepu;
LWMPOINT *epall = lwgeom_extract_endpoints(lwg);
GEOSGeometry *gepall = LWGEOM2GEOS((LWGEOM*)epall, 1);
lwmpoint_free(epall);
if ( ! gepall ) {
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
/* UnaryUnion to remove duplicates */
/* TODO: do it all within pgis using indices */
gepu = GEOSUnaryUnion(gepall);
if ( ! gepu ) {
GEOSGeom_destroy(gepall);
lwerror("GEOSUnaryUnion: %s", lwgeom_geos_errmsg);
return NULL;
}
GEOSGeom_destroy(gepall);
ret = GEOS2LWGEOM(gepu, FLAGS_GET_Z(lwg->flags));
GEOSGeom_destroy(gepu);
if ( ! ret ) {
lwerror("Error during GEOS2LWGEOM");
return NULL;
}
return ret;
}
LWGEOM*
lwgeom_buildarea(const LWGEOM *geom)
{
GEOSGeometry* geos_in;
GEOSGeometry* geos_out;
LWGEOM* geom_out;
int SRID = (int)(geom->srid);
int is3d = FLAGS_GET_Z(geom->flags);
/* Can't build an area from an empty! */
if ( lwgeom_is_empty(geom) )
{
return (LWGEOM*)lwpoly_construct_empty(SRID, is3d, 0);
}
LWDEBUG(3, "buildarea called");
LWDEBUGF(3, "ST_BuildArea got geom @ %p", geom);
initGEOS(lwnotice, lwgeom_geos_error);
geos_in = LWGEOM2GEOS(geom);
if ( 0 == geos_in ) /* exception thrown at construction */
{
lwerror("First argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
geos_out = LWGEOM_GEOS_buildArea(geos_in);
GEOSGeom_destroy(geos_in);
if ( ! geos_out ) /* exception thrown.. */
{
lwerror("LWGEOM_GEOS_buildArea: %s", lwgeom_geos_errmsg);
return NULL;
}
/* If no geometries are in result collection, return NULL */
if ( GEOSGetNumGeometries(geos_out) == 0 )
{
GEOSGeom_destroy(geos_out);
return NULL;
}
geom_out = GEOS2LWGEOM(geos_out, is3d);
GEOSGeom_destroy(geos_out);
#if PARANOIA_LEVEL > 0
if ( geom_out == NULL )
{
lwerror("serialization error");
return NULL;
}
#endif
return geom_out;
}
LWGEOM*
lwgeom_offsetcurve(const LWLINE *lwline, double size, int quadsegs, int joinStyle, double mitreLimit)
{
#if POSTGIS_GEOS_VERSION < 32
lwerror("lwgeom_offsetcurve: GEOS 3.2 or higher required");
#else
GEOSGeometry *g1, *g3;
LWGEOM *lwgeom_result;
LWGEOM *lwgeom_in = lwline_as_lwgeom(lwline);
initGEOS(lwnotice, lwgeom_geos_error);
g1 = (GEOSGeometry *)LWGEOM2GEOS(lwgeom_in);
if ( ! g1 )
{
lwerror("lwgeom_offsetcurve: Geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
#if POSTGIS_GEOS_VERSION < 33
/* Size is always positive for GEOSSingleSidedBuffer, and a flag determines left/right */
g3 = GEOSSingleSidedBuffer(g1, size < 0 ? -size : size,
quadsegs, joinStyle, mitreLimit,
size < 0 ? 0 : 1);
#else
g3 = GEOSOffsetCurve(g1, size, quadsegs, joinStyle, mitreLimit);
#endif
/* Don't need input geometry anymore */
GEOSGeom_destroy(g1);
if (g3 == NULL)
{
GEOSGeom_destroy(g1);
lwerror("GEOSOffsetCurve: %s", lwgeom_geos_errmsg);
return NULL;
}
LWDEBUGF(3, "result: %s", GEOSGeomToWKT(g3));
GEOSSetSRID(g3, lwgeom_get_srid(lwgeom_in));
lwgeom_result = GEOS2LWGEOM(g3, lwgeom_has_z(lwgeom_in));
GEOSGeom_destroy(g3);
if (lwgeom_result == NULL)
{
lwerror("lwgeom_offsetcurve: GEOS2LWGEOM returned null");
return NULL;
}
return lwgeom_result;
#endif /* POSTGIS_GEOS_VERSION < 32 */
}
/* May return LWPOINT or LWMPOINT */
static LWGEOM*
lwgeom_extract_unique_endpoints(const LWGEOM* lwg)
{
#if POSTGIS_GEOS_VERSION < 33
lwerror("The GEOS version this postgis binary "
"was compiled against (%d) doesn't support "
"'GEOSUnaryUnion' function (3.3.0+ required)",
POSTGIS_GEOS_VERSION);
return NULL;
#else /* POSTGIS_GEOS_VERSION >= 33 */
LWGEOM* ret;
GEOSGeometry *gepu;
LWMPOINT *epall = lwgeom_extract_endpoints(lwg);
GEOSGeometry *gepall = LWGEOM2GEOS((LWGEOM*)epall);
lwmpoint_free(epall);
if ( ! gepall ) {
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
/* UnaryUnion to remove duplicates */
/* TODO: do it all within pgis using indices */
gepu = GEOSUnaryUnion(gepall);
if ( ! gepu ) {
GEOSGeom_destroy(gepall);
lwerror("GEOSUnaryUnion: %s", lwgeom_geos_errmsg);
return NULL;
}
GEOSGeom_destroy(gepall);
ret = GEOS2LWGEOM(gepu, FLAGS_GET_Z(lwg->flags));
GEOSGeom_destroy(gepu);
if ( ! ret ) {
lwerror("Error during GEOS2LWGEOM");
return NULL;
}
return ret;
#endif /* POSTGIS_GEOS_VERSION >= 33 */
}
LWGEOM *
lwgeom_normalize(const LWGEOM *geom1)
{
LWGEOM *result ;
GEOSGeometry *g1;
int is3d ;
int srid ;
srid = (int)(geom1->srid);
is3d = FLAGS_GET_Z(geom1->flags);
initGEOS(lwnotice, lwgeom_geos_error);
g1 = LWGEOM2GEOS(geom1);
if ( 0 == g1 ) /* exception thrown at construction */
{
lwerror("First argument geometry could not be converted to GEOS.");
return NULL ;
}
if ( -1 == GEOSNormalize(g1) )
{
lwerror("Error in GEOSNormalize: %s", lwgeom_geos_errmsg);
return NULL; /* never get here */
}
GEOSSetSRID(g1, srid); /* needed ? */
result = GEOS2LWGEOM(g1, is3d);
GEOSGeom_destroy(g1);
if (result == NULL)
{
lwerror("Error performing intersection: GEOS2LWGEOM: %s",
lwgeom_geos_errmsg);
return NULL ; /* never get here */
}
return result ;
}
LWGEOM*
lwgeom_geos_noop(const LWGEOM* geom_in)
{
GEOSGeometry *geosgeom;
LWGEOM* geom_out;
int is3d = FLAGS_GET_Z(geom_in->flags);
initGEOS(lwnotice, lwgeom_geos_error);
geosgeom = LWGEOM2GEOS(geom_in);
if ( ! geosgeom ) {
lwerror("Geometry could not be converted to GEOS: %s",
lwgeom_geos_errmsg);
return NULL;
}
geom_out = GEOS2LWGEOM(geosgeom, is3d);
GEOSGeom_destroy(geosgeom);
if ( ! geom_out ) {
lwerror("GEOS Geometry could not be converted to LWGEOM: %s",
lwgeom_geos_errmsg);
}
return geom_out;
}
/* Initializes and uses GEOS internally */
static LWGEOM*
lwline_split_by_line(const LWLINE* lwline_in, const LWGEOM* blade_in)
{
LWGEOM** components;
LWGEOM* diff;
LWCOLLECTION* out;
GEOSGeometry* gdiff; /* difference */
GEOSGeometry* g1;
GEOSGeometry* g2;
int ret;
/* ASSERT blade_in is LINE or MULTILINE */
assert (blade_in->type == LINETYPE ||
blade_in->type == MULTILINETYPE ||
blade_in->type == POLYGONTYPE ||
blade_in->type == MULTIPOLYGONTYPE );
/* Possible outcomes:
*
* 1. The lines do not cross or overlap
* -> Return a collection with single element
* 2. The lines cross
* -> Return a collection of all elements resulting from the split
*/
initGEOS(lwgeom_geos_error, lwgeom_geos_error);
g1 = LWGEOM2GEOS((LWGEOM*)lwline_in, 0);
if ( ! g1 )
{
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = LWGEOM2GEOS(blade_in, 0);
if ( ! g2 )
{
GEOSGeom_destroy(g1);
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
/* If blade is a polygon, pick its boundary */
if ( blade_in->type == POLYGONTYPE || blade_in->type == MULTIPOLYGONTYPE )
{
gdiff = GEOSBoundary(g2);
GEOSGeom_destroy(g2);
if ( ! gdiff )
{
GEOSGeom_destroy(g1);
lwerror("GEOSBoundary: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = gdiff; gdiff = NULL;
}
/* If interior intersecton is linear we can't split */
ret = GEOSRelatePattern(g1, g2, "1********");
if ( 2 == ret )
{
lwerror("GEOSRelatePattern: %s", lwgeom_geos_errmsg);
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
return NULL;
}
if ( ret )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
lwerror("Splitter line has linear intersection with input");
return NULL;
}
gdiff = GEOSDifference(g1,g2);
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
if (gdiff == NULL)
{
lwerror("GEOSDifference: %s", lwgeom_geos_errmsg);
return NULL;
}
diff = GEOS2LWGEOM(gdiff, FLAGS_GET_Z(lwline_in->flags));
GEOSGeom_destroy(gdiff);
if (NULL == diff)
{
lwerror("GEOS2LWGEOM: %s", lwgeom_geos_errmsg);
return NULL;
}
out = lwgeom_as_lwcollection(diff);
if ( ! out )
{
components = lwalloc(sizeof(LWGEOM*)*1);
components[0] = diff;
out = lwcollection_construct(COLLECTIONTYPE, lwline_in->srid,
NULL, 1, components);
}
else
{
/* Set SRID */
lwgeom_set_srid((LWGEOM*)out, lwline_in->srid);
/* Force collection type */
out->type = COLLECTIONTYPE;
}
return (LWGEOM*)out;
}
/* Initializes and uses GEOS internally */
static LWGEOM*
lwpoly_split_by_line(const LWPOLY* lwpoly_in, const LWLINE* blade_in)
{
LWCOLLECTION* out;
GEOSGeometry* g1;
GEOSGeometry* g2;
GEOSGeometry* g1_bounds;
GEOSGeometry* polygons;
const GEOSGeometry *vgeoms[1];
int i,n;
int hasZ = FLAGS_GET_Z(lwpoly_in->flags);
/* Possible outcomes:
*
* 1. The line does not split the polygon
* -> Return a collection with single element
* 2. The line does split the polygon
* -> Return a collection of all elements resulting from the split
*/
initGEOS(lwgeom_geos_error, lwgeom_geos_error);
g1 = LWGEOM2GEOS((LWGEOM*)lwpoly_in, 0);
if ( NULL == g1 )
{
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g1_bounds = GEOSBoundary(g1);
if ( NULL == g1_bounds )
{
GEOSGeom_destroy(g1);
lwerror("GEOSBoundary: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = LWGEOM2GEOS((LWGEOM*)blade_in, 0);
if ( NULL == g2 )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g1_bounds);
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
vgeoms[0] = GEOSUnion(g1_bounds, g2);
if ( NULL == vgeoms[0] )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
lwerror("GEOSUnion: %s", lwgeom_geos_errmsg);
return NULL;
}
polygons = GEOSPolygonize(vgeoms, 1);
if ( NULL == polygons )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
lwerror("GEOSPolygonize: %s", lwgeom_geos_errmsg);
return NULL;
}
#if PARANOIA_LEVEL > 0
if ( GEOSGeomTypeId(polygons) != COLLECTIONTYPE )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
lwerror("%s [%s] Unexpected return from GEOSpolygonize", __FILE__, __LINE__);
return 0;
}
#endif
/* We should now have all polygons, just skip
* the ones which are in holes of the original
* geometries and return the rest in a collection
*/
n = GEOSGetNumGeometries(polygons);
out = lwcollection_construct_empty(COLLECTIONTYPE, lwpoly_in->srid,
hasZ, 0);
/* Allocate space for all polys */
out->geoms = lwrealloc(out->geoms, sizeof(LWGEOM*)*n);
assert(0 == out->ngeoms);
for (i=0; i<n; ++i)
{
GEOSGeometry* pos; /* point on surface */
const GEOSGeometry* p = GEOSGetGeometryN(polygons, i);
int contains;
pos = GEOSPointOnSurface(p);
if ( ! pos )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
lwerror("GEOSPointOnSurface: %s", lwgeom_geos_errmsg);
return NULL;
}
contains = GEOSContains(g1, pos);
if ( 2 == contains )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
GEOSGeom_destroy(pos);
lwerror("GEOSContains: %s", lwgeom_geos_errmsg);
return NULL;
}
GEOSGeom_destroy(pos);
if ( 0 == contains )
{
/* Original geometry doesn't contain
* a point in this ring, must be an hole
*/
continue;
}
out->geoms[out->ngeoms++] = GEOS2LWGEOM(p, hasZ);
}
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
return (LWGEOM*)out;
}
LWGEOM*
lwgeom_node(const LWGEOM* lwgeom_in)
{
#if POSTGIS_GEOS_VERSION < 33
lwerror("The GEOS version this postgis binary "
"was compiled against (%d) doesn't support "
"'GEOSUnaryUnion' function (3.3.0+ required)",
POSTGIS_GEOS_VERSION);
return NULL;
#else /* POSTGIS_GEOS_VERSION >= 33 */
GEOSGeometry *g1, *gu, *gm;
LWGEOM *ep, *lines;
LWCOLLECTION *col, *tc;
int pn, ln, np, nl;
if ( lwgeom_dimension(lwgeom_in) != 1 ) {
lwerror("Noding geometries of dimension != 1 is unsupported");
return NULL;
}
initGEOS(lwgeom_geos_error, lwgeom_geos_error);
g1 = LWGEOM2GEOS(lwgeom_in);
if ( ! g1 ) {
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
ep = lwgeom_extract_unique_endpoints(lwgeom_in);
if ( ! ep ) {
GEOSGeom_destroy(g1);
lwerror("Error extracting unique endpoints from input");
return NULL;
}
/* Unary union input to fully node */
gu = GEOSUnaryUnion(g1);
GEOSGeom_destroy(g1);
if ( ! gu ) {
lwgeom_free(ep);
lwerror("GEOSUnaryUnion: %s", lwgeom_geos_errmsg);
return NULL;
}
/* Linemerge (in case of overlaps) */
gm = GEOSLineMerge(gu);
GEOSGeom_destroy(gu);
if ( ! gm ) {
lwgeom_free(ep);
lwerror("GEOSLineMerge: %s", lwgeom_geos_errmsg);
return NULL;
}
lines = GEOS2LWGEOM(gm, FLAGS_GET_Z(lwgeom_in->flags));
GEOSGeom_destroy(gm);
if ( ! lines ) {
lwgeom_free(ep);
lwerror("Error during GEOS2LWGEOM");
return NULL;
}
/*
* Reintroduce endpoints from input, using split-line-by-point.
* Note that by now we can be sure that each point splits at
* most _one_ segment as any point shared by multiple segments
* would already be a node. Also we can be sure that any of
* the segments endpoints won't split any other segment.
* We can use the above 2 assertions to early exit the loop.
*/
col = lwcollection_construct_empty(MULTILINETYPE, lwgeom_in->srid,
FLAGS_GET_Z(lwgeom_in->flags),
FLAGS_GET_M(lwgeom_in->flags));
np = lwgeom_ngeoms(ep);
for (pn=0; pn<np; ++pn) { /* for each point */
const LWPOINT* p = (LWPOINT*)lwgeom_subgeom(ep, pn);
nl = lwgeom_ngeoms(lines);
for (ln=0; ln<nl; ++ln) { /* for each line */
const LWLINE* l = (LWLINE*)lwgeom_subgeom(lines, ln);
int s = lwline_split_by_point_to(l, p, (LWMLINE*)col);
if ( ! s ) continue; /* not on this line */
if ( s == 1 ) {
/* found on this line, but not splitting it */
break;
}
/* splits this line */
/* replace this line with the two splits */
if ( lwgeom_is_collection(lines) ) {
tc = (LWCOLLECTION*)lines;
lwcollection_reserve(tc, nl + 1);
while (nl > ln+1) {
tc->geoms[nl] = tc->geoms[nl-1];
--nl;
}
lwgeom_free(tc->geoms[ln]);
tc->geoms[ln] = col->geoms[0];
tc->geoms[ln+1] = col->geoms[1];
tc->ngeoms++;
} else {
lwgeom_free(lines);
/* transfer ownership rather than cloning */
lines = (LWGEOM*)lwcollection_clone_deep(col);
assert(col->ngeoms == 2);
lwgeom_free(col->geoms[0]);
lwgeom_free(col->geoms[1]);
}
/* reset the vector */
assert(col->ngeoms == 2);
col->ngeoms = 0;
break;
}
}
lwgeom_free(ep);
lwcollection_free(col);
lines->srid = lwgeom_in->srid;
return (LWGEOM*)lines;
#endif /* POSTGIS_GEOS_VERSION >= 33 */
}
LWGEOM*
lwgeom_snap(const LWGEOM* geom1, const LWGEOM* geom2, double tolerance)
{
#if POSTGIS_GEOS_VERSION < 33
lwerror("The GEOS version this lwgeom library "
"was compiled against (%d) doesn't support "
"'Snap' function (3.3.0+ required)",
POSTGIS_GEOS_VERSION);
return NULL;
#else /* POSTGIS_GEOS_VERSION >= 33 */
int srid, is3d;
GEOSGeometry *g1, *g2, *g3;
LWGEOM* out;
srid = geom1->srid;
error_if_srid_mismatch(srid, (int)(geom2->srid));
is3d = (FLAGS_GET_Z(geom1->flags) || FLAGS_GET_Z(geom2->flags)) ;
initGEOS(lwnotice, lwgeom_geos_error);
g1 = (GEOSGeometry *)LWGEOM2GEOS(geom1);
if ( 0 == g1 ) /* exception thrown at construction */
{
lwerror("First argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = (GEOSGeometry *)LWGEOM2GEOS(geom2);
if ( 0 == g2 ) /* exception thrown at construction */
{
lwerror("Second argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
GEOSGeom_destroy(g1);
return NULL;
}
g3 = GEOSSnap(g1, g2, tolerance);
if (g3 == NULL)
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
lwerror("GEOSSnap: %s", lwgeom_geos_errmsg);
return NULL;
}
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSSetSRID(g3, srid);
out = GEOS2LWGEOM(g3, is3d);
if (out == NULL)
{
GEOSGeom_destroy(g3);
lwerror("GEOSSnap() threw an error (result LWGEOM geometry formation)!");
return NULL;
}
GEOSGeom_destroy(g3);
return out;
#endif /* POSTGIS_GEOS_VERSION >= 33 */
}
LWGEOM*
lwgeom_union(const LWGEOM *geom1, const LWGEOM *geom2)
{
int is3d;
int srid;
GEOSGeometry *g1, *g2, *g3;
LWGEOM *result;
LWDEBUG(2, "in geomunion");
/* A.Union(empty) == A */
if ( lwgeom_is_empty(geom1) )
return lwgeom_clone(geom2);
/* B.Union(empty) == B */
if ( lwgeom_is_empty(geom2) )
return lwgeom_clone(geom1);
/* ensure srids are identical */
srid = (int)(geom1->srid);
error_if_srid_mismatch(srid, (int)(geom2->srid));
is3d = (FLAGS_GET_Z(geom1->flags) || FLAGS_GET_Z(geom2->flags)) ;
initGEOS(lwnotice, lwgeom_geos_error);
g1 = LWGEOM2GEOS(geom1);
if ( 0 == g1 ) /* exception thrown at construction */
{
lwerror("First argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = LWGEOM2GEOS(geom2);
if ( 0 == g2 ) /* exception thrown at construction */
{
GEOSGeom_destroy(g1);
lwerror("Second argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
LWDEBUGF(3, "g1=%s", GEOSGeomToWKT(g1));
LWDEBUGF(3, "g2=%s", GEOSGeomToWKT(g2));
g3 = GEOSUnion(g1,g2);
LWDEBUGF(3, "g3=%s", GEOSGeomToWKT(g3));
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
if (g3 == NULL)
{
lwerror("GEOSUnion: %s", lwgeom_geos_errmsg);
return NULL; /* never get here */
}
GEOSSetSRID(g3, srid);
result = GEOS2LWGEOM(g3, is3d);
GEOSGeom_destroy(g3);
if (result == NULL)
{
lwerror("Error performing union: GEOS2LWGEOM: %s",
lwgeom_geos_errmsg);
return NULL; /*never get here */
}
return result;
}
LWGEOM *
lwgeom_symdifference(const LWGEOM* geom1, const LWGEOM* geom2)
{
GEOSGeometry *g1, *g2, *g3;
LWGEOM *result;
int is3d;
int srid;
/* A.SymDifference(Empty) == A */
if ( lwgeom_is_empty(geom2) )
return lwgeom_clone(geom1);
/* Empty.DymDifference(B) == Empty */
if ( lwgeom_is_empty(geom1) )
return lwgeom_clone(geom1);
/* ensure srids are identical */
srid = (int)(geom1->srid);
error_if_srid_mismatch(srid, (int)(geom2->srid));
is3d = (FLAGS_GET_Z(geom1->flags) || FLAGS_GET_Z(geom2->flags)) ;
initGEOS(lwnotice, lwgeom_geos_error);
g1 = LWGEOM2GEOS(geom1);
if ( 0 == g1 ) /* exception thrown at construction */
{
lwerror("First argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = LWGEOM2GEOS(geom2);
if ( 0 == g2 ) /* exception thrown at construction */
{
lwerror("Second argument geometry could not be converted to GEOS: %s", lwgeom_geos_errmsg);
GEOSGeom_destroy(g1);
return NULL;
}
g3 = GEOSSymDifference(g1,g2);
if (g3 == NULL)
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
lwerror("GEOSSymDifference: %s", lwgeom_geos_errmsg);
return NULL; /*never get here */
}
LWDEBUGF(3, "result: %s", GEOSGeomToWKT(g3));
GEOSSetSRID(g3, srid);
result = GEOS2LWGEOM(g3, is3d);
if (result == NULL)
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g3);
lwerror("GEOS symdifference() threw an error (result postgis geometry formation)!");
return NULL ; /*never get here */
}
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g3);
return result;
}
LWGEOM *
lwgeom_intersection(const LWGEOM *geom1, const LWGEOM *geom2)
{
LWGEOM *result ;
GEOSGeometry *g1, *g2, *g3 ;
int is3d ;
int srid ;
/* A.Intersection(Empty) == Empty */
if ( lwgeom_is_empty(geom2) )
return lwgeom_clone(geom2);
/* Empty.Intersection(A) == Empty */
if ( lwgeom_is_empty(geom1) )
return lwgeom_clone(geom1);
/* ensure srids are identical */
srid = (int)(geom1->srid);
error_if_srid_mismatch(srid, (int)(geom2->srid));
is3d = (FLAGS_GET_Z(geom1->flags) || FLAGS_GET_Z(geom2->flags)) ;
initGEOS(lwnotice, lwgeom_geos_error);
LWDEBUG(3, "intersection() START");
g1 = LWGEOM2GEOS(geom1);
if ( 0 == g1 ) /* exception thrown at construction */
{
lwerror("First argument geometry could not be converted to GEOS.");
return NULL ;
}
g2 = LWGEOM2GEOS(geom2);
if ( 0 == g2 ) /* exception thrown at construction */
{
lwerror("Second argument geometry could not be converted to GEOS.");
GEOSGeom_destroy(g1);
return NULL ;
}
LWDEBUG(3, " constructed geometrys - calling geos");
LWDEBUGF(3, " g1 = %s", GEOSGeomToWKT(g1));
LWDEBUGF(3, " g2 = %s", GEOSGeomToWKT(g2));
/*LWDEBUGF(3, "g2 is valid = %i",GEOSisvalid(g2)); */
/*LWDEBUGF(3, "g1 is valid = %i",GEOSisvalid(g1)); */
g3 = GEOSIntersection(g1,g2);
LWDEBUG(3, " intersection finished");
if (g3 == NULL)
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
lwerror("Error performing intersection: %s",
lwgeom_geos_errmsg);
return NULL; /* never get here */
}
LWDEBUGF(3, "result: %s", GEOSGeomToWKT(g3) ) ;
GEOSSetSRID(g3, srid);
result = GEOS2LWGEOM(g3, is3d);
if (result == NULL)
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g3);
lwerror("Error performing intersection: GEOS2LWGEOM: %s",
lwgeom_geos_errmsg);
return NULL ; /* never get here */
}
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g3);
return result ;
}
GEOSGeometry *
LWGEOM2GEOS(const LWGEOM *lwgeom)
{
GEOSCoordSeq sq;
GEOSGeom g, shell;
GEOSGeom *geoms = NULL;
/*
LWGEOM *tmp;
*/
uint32_t ngeoms, i;
int geostype;
#if LWDEBUG_LEVEL >= 4
char *wkt;
#endif
LWDEBUGF(4, "LWGEOM2GEOS got a %s", lwtype_name(lwgeom->type));
if (lwgeom_has_arc(lwgeom))
{
LWDEBUG(3, "LWGEOM2GEOS: arced geometry found.");
lwerror("Exception in LWGEOM2GEOS: curved geometry not supported.");
return NULL;
}
switch (lwgeom->type)
{
LWPOINT *lwp = NULL;
LWPOLY *lwpoly = NULL;
LWLINE *lwl = NULL;
LWCOLLECTION *lwc = NULL;
#if POSTGIS_GEOS_VERSION < 33
POINTARRAY *pa = NULL;
#endif
case POINTTYPE:
lwp = (LWPOINT *)lwgeom;
if ( lwgeom_is_empty(lwgeom) )
{
#if POSTGIS_GEOS_VERSION < 33
pa = ptarray_construct_empty(lwgeom_has_z(lwgeom), lwgeom_has_m(lwgeom), 2);
sq = ptarray_to_GEOSCoordSeq(pa);
shell = GEOSGeom_createLinearRing(sq);
g = GEOSGeom_createPolygon(shell, NULL, 0);
#else
g = GEOSGeom_createEmptyPolygon();
#endif
}
else
{
sq = ptarray_to_GEOSCoordSeq(lwp->point);
g = GEOSGeom_createPoint(sq);
}
if ( ! g )
{
/* lwnotice("Exception in LWGEOM2GEOS"); */
return NULL;
}
break;
case LINETYPE:
lwl = (LWLINE *)lwgeom;
if ( lwl->points->npoints == 1 ) {
/* Duplicate point, to make geos-friendly */
lwl->points = ptarray_addPoint(lwl->points,
getPoint_internal(lwl->points, 0),
FLAGS_NDIMS(lwl->points->flags),
lwl->points->npoints);
}
sq = ptarray_to_GEOSCoordSeq(lwl->points);
g = GEOSGeom_createLineString(sq);
if ( ! g )
{
/* lwnotice("Exception in LWGEOM2GEOS"); */
return NULL;
}
break;
case POLYGONTYPE:
lwpoly = (LWPOLY *)lwgeom;
if ( lwgeom_is_empty(lwgeom) )
{
#if POSTGIS_GEOS_VERSION < 33
POINTARRAY *pa = ptarray_construct_empty(lwgeom_has_z(lwgeom), lwgeom_has_m(lwgeom), 2);
sq = ptarray_to_GEOSCoordSeq(pa);
shell = GEOSGeom_createLinearRing(sq);
g = GEOSGeom_createPolygon(shell, NULL, 0);
#else
g = GEOSGeom_createEmptyPolygon();
#endif
}
else
{
sq = ptarray_to_GEOSCoordSeq(lwpoly->rings[0]);
/* TODO: check ring for being closed and fix if not */
shell = GEOSGeom_createLinearRing(sq);
if ( ! shell ) return NULL;
/*lwerror("LWGEOM2GEOS: exception during polygon shell conversion"); */
ngeoms = lwpoly->nrings-1;
if ( ngeoms > 0 )
geoms = malloc(sizeof(GEOSGeom)*ngeoms);
for (i=1; i<lwpoly->nrings; ++i)
{
sq = ptarray_to_GEOSCoordSeq(lwpoly->rings[i]);
geoms[i-1] = GEOSGeom_createLinearRing(sq);
if ( ! geoms[i-1] )
{
--i;
while (i) GEOSGeom_destroy(geoms[--i]);
free(geoms);
GEOSGeom_destroy(shell);
return NULL;
}
/*lwerror("LWGEOM2GEOS: exception during polygon hole conversion"); */
}
g = GEOSGeom_createPolygon(shell, geoms, ngeoms);
if (geoms) free(geoms);
}
if ( ! g ) return NULL;
break;
case MULTIPOINTTYPE:
case MULTILINETYPE:
case MULTIPOLYGONTYPE:
case COLLECTIONTYPE:
if ( lwgeom->type == MULTIPOINTTYPE )
geostype = GEOS_MULTIPOINT;
else if ( lwgeom->type == MULTILINETYPE )
geostype = GEOS_MULTILINESTRING;
else if ( lwgeom->type == MULTIPOLYGONTYPE )
geostype = GEOS_MULTIPOLYGON;
else
geostype = GEOS_GEOMETRYCOLLECTION;
lwc = (LWCOLLECTION *)lwgeom;
ngeoms = lwc->ngeoms;
if ( ngeoms > 0 )
geoms = malloc(sizeof(GEOSGeom)*ngeoms);
for (i=0; i<ngeoms; ++i)
{
GEOSGeometry* g = LWGEOM2GEOS(lwc->geoms[i]);
if ( ! g )
{
while (i) GEOSGeom_destroy(geoms[--i]);
free(geoms);
return NULL;
}
geoms[i] = g;
}
g = GEOSGeom_createCollection(geostype, geoms, ngeoms);
if ( geoms ) free(geoms);
if ( ! g ) return NULL;
break;
default:
lwerror("Unknown geometry type: %d - %s", lwgeom->type, lwtype_name(lwgeom->type));
return NULL;
}
GEOSSetSRID(g, lwgeom->srid);
#if LWDEBUG_LEVEL >= 4
wkt = GEOSGeomToWKT(g);
LWDEBUGF(4, "LWGEOM2GEOS: GEOSGeom: %s", wkt);
free(wkt);
#endif
return g;
}
/* Initializes and uses GEOS internally */
static LWGEOM*
lwline_split_by_line(const LWLINE* lwline_in, const LWLINE* blade_in)
{
LWGEOM** components;
LWGEOM* diff;
LWCOLLECTION* out;
GEOSGeometry* gdiff; /* difference */
GEOSGeometry* g1;
GEOSGeometry* g2;
int ret;
/* Possible outcomes:
*
* 1. The lines do not cross or overlap
* -> Return a collection with single element
* 2. The lines cross
* -> Return a collection of all elements resulting from the split
*/
initGEOS(lwgeom_geos_error, lwgeom_geos_error);
g1 = LWGEOM2GEOS((LWGEOM*)lwline_in);
if ( ! g1 )
{
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = LWGEOM2GEOS((LWGEOM*)blade_in);
if ( ! g2 )
{
GEOSGeom_destroy(g1);
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
/* If interior intersecton is linear we can't split */
ret = GEOSRelatePattern(g1, g2, "1********");
if ( 2 == ret )
{
lwerror("GEOSRelatePattern: %s", lwgeom_geos_errmsg);
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
return NULL;
}
if ( ret )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
lwerror("Splitter line has linear intersection with input");
return NULL;
}
gdiff = GEOSDifference(g1,g2);
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
if (gdiff == NULL)
{
lwerror("GEOSDifference: %s", lwgeom_geos_errmsg);
return NULL;
}
diff = GEOS2LWGEOM(gdiff, FLAGS_GET_Z(lwline_in->flags));
GEOSGeom_destroy(gdiff);
if (NULL == diff)
{
lwerror("GEOS2LWGEOM: %s", lwgeom_geos_errmsg);
return NULL;
}
if ( ! lwtype_is_collection(diff->type) )
{
components = lwalloc(sizeof(LWGEOM*)*1);
components[0] = diff;
out = lwcollection_construct(COLLECTIONTYPE, lwline_in->srid,
NULL, 1, components);
}
else
{
out = lwcollection_construct(COLLECTIONTYPE, lwline_in->srid,
NULL, ((LWCOLLECTION*)diff)->ngeoms,
((LWCOLLECTION*)diff)->geoms);
}
return (LWGEOM*)out;
}
