Datum LWGEOM_line_locate_point(PG_FUNCTION_ARGS)
{
GSERIALIZED *geom1 = PG_GETARG_GSERIALIZED_P(0);
GSERIALIZED *geom2 = PG_GETARG_GSERIALIZED_P(1);
LWLINE *lwline;
LWPOINT *lwpoint;
POINTARRAY *pa;
POINT4D p, p_proj;
double ret;
if ( gserialized_get_type(geom1) != LINETYPE )
{
elog(ERROR,"line_locate_point: 1st arg isn't a line");
PG_RETURN_NULL();
}
if ( gserialized_get_type(geom2) != POINTTYPE )
{
elog(ERROR,"line_locate_point: 2st arg isn't a point");
PG_RETURN_NULL();
}
error_if_srid_mismatch(gserialized_get_srid(geom1), gserialized_get_srid(geom2));
lwline = lwgeom_as_lwline(lwgeom_from_gserialized(geom1));
lwpoint = lwgeom_as_lwpoint(lwgeom_from_gserialized(geom2));
pa = lwline->points;
lwpoint_getPoint4d_p(lwpoint, &p);
ret = ptarray_locate_point(pa, &p, NULL, &p_proj);
PG_RETURN_FLOAT8(ret);
}
double
lwgeom_interpolate_point(const LWGEOM *lwin, const LWPOINT *lwpt)
{
POINT4D p, p_proj;
double ret = 0.0;
if ( ! lwin )
lwerror("lwgeom_interpolate_point: null input geometry!");
if ( ! lwgeom_has_m(lwin) )
lwerror("Input geometry does not have a measure dimension");
if ( lwgeom_is_empty(lwin) || lwpoint_is_empty(lwpt) )
lwerror("Input geometry is empty");
switch ( lwin->type )
{
case LINETYPE:
{
LWLINE *lwline = lwgeom_as_lwline(lwin);
lwpoint_getPoint4d_p(lwpt, &p);
ret = ptarray_locate_point(lwline->points, &p, NULL, &p_proj);
ret = p_proj.m;
break;
}
default:
lwerror("This function does not accept %s geometries.", lwtype_name(lwin->type));
}
return ret;
}
/**
* 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;
}
/**
* Clip an input POINT between two values, on any ordinate input.
*/
LWCOLLECTION*
lwpoint_clip_to_ordinate_range(const LWPOINT *point, char ordinate, double from, double to)
{
LWCOLLECTION *lwgeom_out = NULL;
char hasz, hasm;
POINT4D p4d;
double ordinate_value;
/* Nothing to do with NULL */
if ( ! point )
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(lwpoint_as_lwgeom(point));
hasm = lwgeom_has_m(lwpoint_as_lwgeom(point));
/* Prepare return object */
lwgeom_out = lwcollection_construct_empty(MULTIPOINTTYPE, point->srid, hasz, hasm);
/* Test if ordinate is in range */
lwpoint_getPoint4d_p(point, &p4d);
ordinate_value = lwpoint_get_ordinate(&p4d, ordinate);
if ( from <= ordinate_value && to >= ordinate_value )
{
LWPOINT *lwp = lwpoint_clone(point);
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;
}
