[Mesa-dev] gallium-array-textures branch

[Corbin Simpson]

On Mon, Jun 14, 2010 at 4:09 AM, Roland Scheidegger <sroland at vmware.com> wrote:
> I'm planning to merge this branch soon, though I'll fix some broken things
> first. In any case, the probably most fundamental change is that
> get_tex_surface not only got renamed (to create_surface) but also moved to
> context. In short, pipe_surface is not (or no longer as there were free
> standing surfaces once upon a time in gallium) some kind of "2d surface"
> which should be used in (non-rendering) state trackers to move any kind of
> images around. pipe_surface is meant to be used to attach resources to
> depthstencil and color render target outputs (similar to DX10 DepthStencil
> and RenderTarget Views).
> One thing though I'm not quite sure is if for array textures, the same field
> should be used in the resource as for storing depth of 3d textures (the
> depth0 field). Using the same "layer" field both for faces, array index and
> 3d depth seems to make a lot of sense for transfers, the sampler views and
> in pipe_surface, but I'm not sure the same field should be used in the
> resource itself. I've actually converted some code to do that (but not quite
> all for instance the mesa state tracker is broken there).
> The reason for using the same field would be that it's mutually exclusive
> anyway (unless someone introduces 3d array textures...), hence not really 2
> fields are necessary. But OTOH depth behaves differently to arraysize (and
> cube faces) because it doesn't get minified for smaller mips. So if someone
> has convincing reasons what should be preferred I'll follow it :-).
> One this is for sure though we need some way to store array size, and cube
> maps will follow that pattern since for resource handling they are pretty
> much the same as a 2d array texture with array size of 6.

This all seems fine. Drivers for pre-texture-array chipsets can handle
all this by forcing off trilinear filtering, right?

~ C.

-- 
When the facts change, I change my mind. What do you do, sir? ~ Keynes

Corbin Simpson
<MostAwesomeDude at gmail.com>