Hi,

the link you have is setting variable this_cross, and L526 sets
first_cross from it if it was not set and there is LEFT or RIGHT cross
(not no-cross and not COLLINEAR). Looks expected to me.

On Sat, Apr 18, 2020 at 6:32 PM Kohei KaiGai <[email protected]> wrote:
>
> Hello,
>
> I noticed a strange code at liblwgeom/lwalgorithm.c
> https://github.com/postgis/postgis/blob/master/liblwgeom/lwalgorithm.c#L509
>
> lwline_crossing_direction() is the main logic of ST_LineCrossingDirection.
> It walks on all the edges of the supplied geometry (line), and calls
> lw_segment_intersects to check intersections.
>
> It looks to me the local variable 'first_cross' is used to remember the first
> result from the lw_segment_intersects, however, it saves different value
> on the second if-block at L526.
>
> Is it expected? Or, just mistake by copy & paste?
>
> Best regards,
> --
> HeteroDB, Inc / The PG-Strom Project
> KaiGai Kohei <[email protected]>
> _______________________________________________
> postgis-users mailing list
> [email protected]
> https://lists.osgeo.org/mailman/listinfo/postgis-users



-- 
Darafei Praliaskouski
Support me: http://patreon.com/komzpa
_______________________________________________
postgis-users mailing list
[email protected]
https://lists.osgeo.org/mailman/listinfo/postgis-users

Reply via email to