On 10/06/16 15:05, Ville Syrjälä wrote: >> I'm not sure what's the common way, but tilcdc doesn't support alpha. >> ARGB works, of course, by ignoring A, but... If an userspace app creates >> ARGB buffer, does the app expect alpha to work? > > I think what we decided a while ago (at least for i915, but would be good > to use the same convention everywhere) was that ARGB will be assumed to be > pre-multiplied and will enable blending using 1.0*sc+(1.0-sa)*dc as the > function. There have been some efforts at defining some new properties to > control the blend equation, but I guess those got bogged down again.
Ok, but that's a bit different topic. The question here is, if the HW doesn't support alpha (no planes, so nothing to blend), should it accept ARGB or not. Tomi -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: OpenPGP digital signature URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20160610/6ec20e8a/attachment.sig>