[PD] [pix_crop] offY incoherence

[patko]

----- "cyrille henry" <ch at chnry.net> a écrit :

> openGL coordinate can easily be change using the perspec message to
> gemwin.
> 

Allright, then if I want to have gemwin coordinates system adapted to the blob,
I'd need to find out how to multiply perspect values to have my zeros at the lower corner left
and my ones to higher corner right.

 By fiddling with numberboxes I've figured out that any windows with a 4:3 ratio has one horizontal
unity that is about 5.33 and vertical unity about 4.
 So it's really tricky to get values that are only between 0 and 1
inside the edges of the rendering window.

 In fact , at the end it's far easier to multiply the values outputed by [pix_blob] on x by 10.66 and remove 5.33,
and on y by 8 and remove 4, or divide gemmouse values by gemwin dimen and then multiplying by the same values.

 Is there a way to not-have-to fiddle values for getting an accurate positioning of objects in gemwin?