Anyone noticed a considerable speed difference between 2D ortho view and a 3D frustrum view when displaying the same data (e.g. 2D planar sprites)?

Do those folks out there who have thousands of sprites on-screen all use ortho?

I don't think there should technically be any difference in performance should there? I mean they're both transformed to the same unit cube, using the same pipeline, aren't they?

I wasn't sure if the GPU might have an easier time in ortho, as it doesn't have to deal with perspective correction of texels.

However, if they use exactly the same pipeline, then I'll have to look for some other reason for my iffy performance. :-)

Thanks, Jake.