> From: Bert Freudenberg <bert at isg.cs.uni-magdeburg.de>
>
>
> Yep. I think Squeak could benefit from factoring out the compositing
> (bitblt to display) operations so they can be hardware-accelerated.
> However, there would have to be a platform-specific plugin to encapsulate
> the specifics.  In contrast, OpenGL allows the same kind of compositing
> operations and works across multiple platforms so a single implementation
> can be shared. Apple's Aqua shows that OpenGL indeed is a viable
> foundation for a windowing system. Can you imagine a scenario where
> X Render support would be benefitial over OpenGL?
>

Depends what you are doing: if you are doing serious 3D: do OpenGL.

The issue comes up in 2 D graphics though that it tends be painted
once, and the people stare at the results for a while.

As I understand it, OpenGL will tend to have "interesting" artifacts
at the boundaries between triangles: these tend not to be noticed
in 3D applications due to the rapid repaint, but are often highly
objectionable in 2D apps.

BTW, Keith Packard and Carl Worth are working on a client library for
rendering that will either push pixels or use Render when it is done,
you might think of using it it (along with the really georgeous spline
stuff they are doing) with different back ends.  This is to allow apps
to convert to a new API and not care if the server has render or not.
I suspect this is 6 months from completion.

Think of render as putting the best of Adobe PDF 1.4 in your window system;
all the compositing, splines, etc are then doable (splines are decomposed
to trapezoids, the primitive that Render uses).
                       - Jim

--
Jim Gettys
Cambridge Research Laboratory
HP Labs, Hewlett-Packard Company
Jim.Gettys at hp.com