Re: The big divide - graphics contexts and window servers

[Philippe C.D. Robert]

On Mon, 18 Mar 2002, Jeff Teunissen wrote:
> Pete French wrote:
> > > OpenGL is designed for 3D, and it's not happy with 2D. Most GL
> > > implementations don't accelerate 2D operations beyond throwing a quad
> > > on the screen, and some even leave it incomplete.
> > 
> > Are you sure about this ? I thought there wernt concepts of '2D' and
> > '3D' in OpenGL - you just provide a transformation matrix, and if that
> > happens to be 'flat' so that the points get mapped onto one plane then
> > you have 2D and the library knowns nothing about it.
> 
> Of course the library knows everything about it, the library is what has to
> draw it!  The difference is there are fast paths and slow paths in any GL
> pipeline, and "2D" stuff is usually slow-pathed because there's usually not
> enough of it to matter.

What do you mean by 2D stuff exactly? Could you give an example maybe? 

My guess is that 2D does not exist at all, there is no special path for
2D rendering in commodity drivers. Thus 2D is as slow or fast as 3D. But of
course this is just a guess, I did not looked at sources to proof it.

-Phil
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