/*
* Optional SRID
*/
static int lwgeom_wkb_needs_srid(const LWGEOM *geom, uint8_t variant)
{
/* Sub-components of collections inherit their SRID from the parent.
We force that behavior with the WKB_NO_SRID flag */
if ( variant & WKB_NO_SRID )
return LW_FALSE;
/* We can only add an SRID if the geometry has one, and the
WKB form is extended */
if ( (variant & WKB_EXTENDED) && lwgeom_has_srid(geom) )
return LW_TRUE;
/* Everything else doesn't get an SRID */
return LW_FALSE;
}
/**
* WKT emitter function. Allocates a new *char and fills it with the WKT
* representation. If size_out is not NULL, it will be set to the size of the
* allocated *char.
*
* @param variant Bitmasked value, accepts one of WKT_ISO, WKT_SFSQL, WKT_EXTENDED.
* @param precision Number of significant digits in the output doubles.
* @param size_out If supplied, will return the size of the returned string,
* including the null terminator.
*/
char* lwgeom_to_wkt(const LWGEOM *geom, uint8_t variant, int precision, size_t *size_out)
{
stringbuffer_t *sb;
char *str = NULL;
if ( geom == NULL )
return NULL;
sb = stringbuffer_create();
/* Extended mode starts with an "SRID=" section for geoms that have one */
if ( (variant & WKT_EXTENDED) && lwgeom_has_srid(geom) )
{
stringbuffer_aprintf(sb, "SRID=%d;", geom->srid);
}
lwgeom_to_wkt_sb(geom, sb, precision, variant);
if ( stringbuffer_getstring(sb) == NULL )
{
lwerror("Uh oh");
return NULL;
}
str = stringbuffer_getstringcopy(sb);
if ( size_out )
*size_out = stringbuffer_getlength(sb) + 1;
stringbuffer_destroy(sb);
return str;
}
