[GLLUG] X Window Managers

Sean picasso@madflower.com
Fri, 13 Dec 2002 13:45:21 -0500 (EST)


On Fri, 13 Dec 2002, Jo Dillon wrote:

>   Huh? You sure? It's displaying onto X11, not a Display PostScript
> server. And there's nothing /that/ special about Display PS/PDF, it's
> just a graphics language...most GUIs are flinging bitmaps around anyway.
> If X11 had a decent StretchBlt built in it could do most of the same things.

IIRC AfterStep uses ghostcript for the rasterization engine so it 
rasterizes on the fly. Thus the moving graphics are just rasterizations of 
PS vector objects into bitmaps. The difference is in the clarity of images 
when you stretch them or magnify them, because you are dealing with 
vectorized images as your source instead of bitmaps. 

Any Stretchblt whatever libraries don't have enough information available
to them to make good images because you are trying to reconstruct data
that is not there, so it is all guesswork.

The BEST example is to take an EPS in Illustrator/Freehand/etc, blow it up 
to about 600x crop it, then stretch it to fullsize. 
Do the same thing with Photoshop/Gimp. The differences are quite obvious 
even to an untrained eye.