char *msudf_convexHull(UDF_INIT *initid,UDF_ARGS *args, char *buf,
unsigned long *length, char *is_null, char *error)
{
char *result;
GEOSGeom geom1,geom2;
DEBUG("msudf_convexHull");
geom1 = msudf_getGeometry((unsigned char *)args->args[0],args->lengths[0]);
if (geom1 == NULL) {
strcpy(error,"Invalid geometry.");
*is_null = 1;
return NULL;
}
geom2 = GEOSConvexHull(geom1);
if (geom2 != NULL) {
GEOSSetSRID(geom2,GEOSGetSRID(geom1));
result = msudf_returnGeometry(initid,length,geom2);
GEOSGeom_destroy(geom1);
GEOSGeom_destroy(geom2);
return result;
} else {
GEOSGeom_destroy(geom1);
*is_null = 1;
return NULL;
}
}
void object::test<1>()
{
input_ = GEOSGeomFromWKT("MULTIPOINT (130 240, 130 240, 130 240, 570 240, 570 240, 570 240, 650 240)");
ensure( 0 != input_ );
expected_ = GEOSGeomFromWKT("LINESTRING (130 240, 650 240, 130 240)");
ensure( 0 != expected_ );
GEOSGeometry* output = GEOSConvexHull(input_);
ensure( 0 != output );
ensure( 0 == GEOSisEmpty(output) );
// TODO
//ensure( 0 != GEOSEquals(output, expected_));
}
shapeObj *msGEOSConvexHull(shapeObj *shape)
{
#ifdef USE_GEOS
GEOSGeom g1, g2;
if(!shape) return NULL;
if(!shape->geometry) /* if no geometry for the shape then build one */
shape->geometry = (GEOSGeom) msGEOSShape2Geometry(shape);
g1 = (GEOSGeom) shape->geometry;
if(!g1) return NULL;
g2 = GEOSConvexHull(g1);
return msGEOSGeometry2Shape(g2);
#else
msSetError(MS_GEOSERR, "GEOS support is not available.", "msGEOSConvexHull()");
return NULL;
#endif
}
