/**
* Clip an input MULTIPOINT between two values, on any ordinate input.
*/
LWCOLLECTION*
lwmpoint_clip_to_ordinate_range(const LWMPOINT *mpoint, char ordinate, double from, double to)
{
LWCOLLECTION *lwgeom_out = NULL;
char hasz, hasm;
int i;
/* Nothing to do with NULL */
if ( ! mpoint )
lwerror("Null input geometry.");
/* Ensure 'from' is less than 'to'. */
if ( to < from )
{
double t = from;
from = to;
to = t;
}
/* Read Z/M info */
hasz = lwgeom_has_z(lwmpoint_as_lwgeom(mpoint));
hasm = lwgeom_has_m(lwmpoint_as_lwgeom(mpoint));
/* Prepare return object */
lwgeom_out = lwcollection_construct_empty(MULTIPOINTTYPE, mpoint->srid, hasz, hasm);
/* For each point, is its ordinate value between from and to? */
for ( i = 0; i < mpoint->ngeoms; i ++ )
{
POINT4D p4d;
double ordinate_value;
lwpoint_getPoint4d_p(mpoint->geoms[i], &p4d);
ordinate_value = lwpoint_get_ordinate(&p4d, ordinate);
if ( from <= ordinate_value && to >= ordinate_value )
{
LWPOINT *lwp = lwpoint_clone(mpoint->geoms[i]);
lwcollection_add_lwgeom(lwgeom_out, lwpoint_as_lwgeom(lwp));
}
}
/* Set the bbox */
lwgeom_drop_bbox((LWGEOM*)lwgeom_out);
lwgeom_add_bbox((LWGEOM*)lwgeom_out);
return lwgeom_out;
}
static LWMPOINT*
lwmpoint_locate_along(const LWMPOINT *lwin, double m, double offset)
{
LWGEOM *lwg = lwmpoint_as_lwgeom(lwin);
LWMPOINT *lwout = NULL;
int i;
/* Construct return */
lwout = lwmpoint_construct_empty(lwgeom_get_srid(lwg), lwgeom_has_z(lwg), lwgeom_has_m(lwg));
for ( i = 0; i < lwin->ngeoms; i++ )
{
double point_m = lwpoint_get_m(lwin->geoms[i]);
if ( FP_EQUALS(m, point_m) )
{
lwmpoint_add_lwpoint(lwout, lwpoint_clone(lwin->geoms[i]));
}
}
return lwout;
}
void
lwmpoint_release(LWMPOINT *lwmpoint)
{
lwgeom_release(lwmpoint_as_lwgeom(lwmpoint));
}
