RE: [Algorithms] OpenGL LockArrayEXT ... workaround

[Ignacio C. <i6...@ho...>]

Brian Sharp wrote:
> My conference?
>
> Any information I have on Q3A is pretty much hearsay from Brian Hook.  Or
> maybe you're referring to Brian Hook, not Brian Sharp?  We're more
> different than our last names: I never worked for id. ;-)

hoops, sorry, you are completely right, i meant Brian Hook :-)

> ...
>
> I'm not really sure what the motivation would be for a driver to not
> optimize arrays over a certain size.  I mean, they could only pretransform
> a set number and treat any more as regular verts to be
> transformed.  Hmm.  Especially if it's a hardware T&L implementation, where
> you'd obviously want to have a tiered caching system in the driver already,
> capable of locked arrays on the host bigger than your hardware cache.  I'm
> confused.

yes, that's what happens on the geforce, that has a limit of 65536 vertexes, because indexes must be
lower than that.

I got this from nvidia site:

"There is an optimal size for vertex buffers - a fact which is not intuitively obvious.
You should aim for around 2000 vertices per buffer or for around 64K of RAM used."

"GeForce products require indices to not exceed 65535. If more indices are
necessary, break the object into smaller parts."


PD: i will send this message also to the OpenGL Gamedev list, so if you want to continue this
thread, do it there.


Ignacio Castano
ca...@cr...