[GEM-dev] pix_crop y coordinates

Matteo Sisti Sette matteosistisette at gmail.com
Wed Mar 17 22:22:54 CET 2010


Hi,

I'm realising that pix_crop x/y coordinates work as follows:

- x grows from left to right
- y grows from bottom to top

Isn't it a bit weird (the y part)? I know coordinate systems are always 
arbitrary but, aren't digital images rows almost universally counted 
from top to bottom? Isn't that even how they are stored in image files 
and memory?

You may argue that this is for uniformity with Gem's coordinate system 
that has the Y axis pointing upward, but then pixels are not gem units....

Is there a clear advantage in using this convention against the almost 
universal one? Or am I plain wrong about the latter being an almost 
universal convention?

thanks
m.

-- 
Matteo Sisti Sette
matteosistisette at gmail.com
http://www.matteosistisette.com




More information about the GEM-dev mailing list