Re: [Gzz] Background

[Tuomas Lukka]

> Ah, ok. In that case, I *would* suggest special-casing this in GL, 
> simply always drawing cs 0 first, because it is *the* logical place to 
> put the bg vob.

I'd strongly prefer using something symbolic, like Vob.BEGINNING
as the name of the coordsys, or something?

[ reorg'd for answers]
>I'd 
> prefer to think about the bg vob as non-magical, just being a big 
> rectangle of some color, so that it could be also used to render the 
> background of e.g. cells.

Not really doable since glClear is quite a bit faster than rastering
a rectangle. 

> Or hmm-- actually, I do need a bit more explanation here: why does the 
> bg vob have to clear the Z buffer? Why can't the same routine that goes 
> through the vobs and puts them into GL also clean the Z buffer? -- 

If you are clearing DEPTH and COLOR buffers at the same time,
it's more efficient to do them at the same time, not separately.

Also, that would be putting too much functionality in there.
I want to have the ability to decide how to clean it outside the C++
and the GLScreen code.

It's also possible to not want to clear it sometimes.

        Tuomas