sourceforge.net/apps/mediawiki/construct/index.php
Yeah I read that, what I mean is that I based an effect (another version of this one) around the hotspot, so it's centered on it.... and changing the hotspot in the image editor doesn't seem to have any effect.
Are you sure that the correct values for the hotspot are being passed to shaders? it seems to me it's always passing the center.
So about that angle, I guess I'd have to take in an angle via parameters. And get object-space coordinates based on angle parameter, hotspot and pixelwidth/height. screw object size, I guess :s
PS: Just noticed, hotspot coords are being passed correctly on the runtime, just not in the editor!