[postgis-users] new functions

[Peter Korduan]

Am 09.01.2012 21:12, schrieb Mike Toews:
> Also another comment for your transrotate function: you can use 1 call
> to ST_Affine, rather than 3 indirect calls with
> "st_rotate(st_translate(st_rotate(". You just need to wrangle the
> trigonometry in the affine transformation matrix correctly.
>
> I have an enhancement for a st_rotate with a point of origin in trac,
> where you can see how to use ST_Affine for this purpose:
> http://trac.osgeo.org/postgis/ticket/1251
>
> -Mike
Yes Mike, my transrotate function is a special case of an affine 
transformation. I have to consider the quadrants for the trigonometry 
calculation when i use st_affine. I will check it out. Thanks.
Even if the form one after another shows exactly what happens, other 
than in the affine transformation.

To the second comment with the point of origin:
Nice to have it, but i think in my case its not necessary if rotating in 
one direction and than in the opposite with the same origin.

But nevertheless, many thanks for the comments, nice conversation.

Peter