[postgis-devel] getPoint_internal dangerous?

[Björn Harrtell]

I want to mutate one axis of the points in a POINTARRAY in the most
efficient way.

Something similar to ptarray_longitude_shift, see:
https://github.com/postgis/postgis/blob/svn-trunk/liblwgeom/ptarray.c#L1393

I see memcpy being used there and other places and afaik it has something
to do with fears of struct misalignment.

Does this mean I should most definitely not do this? :)

POINT2D *p = (POINT2D *) getPoint_internal(pa, 0);
p->y = extent - p->y;

Regards,
Björn
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