On 07/23/2014 07:41 PM, Matt Turner wrote: > On Wed, Jul 23, 2014 at 3:16 PM, Ian Romanick <i...@freedesktop.org> wrote: >> On 07/22/2014 12:09 PM, Neil Roberts wrote: >>> Here's a first attempt at a patch series to implement BPTC texture >>> compression in the i965 driver on Gen>=7. >>> >>> Getting it to work on the hardware is pretty trivial as it's just a >>> case of adding some new Mesa format enums and then plugging them >>> together with the right Intel surface type. However GL requires that >>> you are able to get the library to compress textures on the fly so we >>> need a compressor too. I think for BPTC it doesn't really make much >>> sense to actually use this because it takes a very long time to search >>> the entire space and compress an image properly. For example the >>> NVidia compressor takes in the order of an hour for a full-screen >>> image. Instead I've just done the minimal work needed to get something >>> that gives vaguely passable results. >> >> Is that NVIDIA's off-line compression tool, or is that the compressor in >> the driver? A brute-force compressor will be very, very slow for BPTC. >> There are other approaches that are much faster without sacrificing >> very much quality. > > I suggested http://squish.paradice-insight.us/ which appears to be > down now. It has a (MIT licensed) BC7 compressor and no free BC6H > compressor. I suggested using it as an external dependency and > contributing a BC6H compressor back. > > I think the github repo is https://github.com/Ethatron/squish-ccr > > I was thinking one of the cool things we might be able to do a ETC2 -> > BC7 transcode on platforms without ETC2 hardware decompression. We > won't be able to do that without a good compressor.
I had forgotten about that idea. There is value in that. Though, I suspect we'd want to do that transcode on the GPU, and probably do it block-by-block as Neil suggests. That's probably step 9, and we're still on step 2. :) _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev