<div class="gmail_quote">On Tue, May 18, 2010 at 10:42 PM, Roland Scheidegger <<a href="mailto:sroland@vmware.com">sroland@vmware.com</a>> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <div><div></div><div class="h5">On 18.05.2010 22:23, Dave Airlie wrote: > On Wed, May 19, 2010 at 3:04 AM, Roland Scheidegger <<a href="mailto:sroland@vmware.com">sroland@vmware.com</a>> wrote: >> Hi, >> >> I plan to merge the gallium-msaa branch to master soon. >> It's actually a bit of a misnomer since the conceptually more important >> changes in there are about blits... >> >> Here's a short summary what this is about: >> blits now operate on resources, not surfaces (surface_copy/fill -> >> resource_copy/fill_region). Note that overlapping blits are no longer >> permitted (half the code always assumed this wasn't the case), and these >> functions are now mandatory (most of the code using these just checked >> for their presence and if not used util_surface_copy instead, hence it >> seems cleaner if drivers plug that in themselves, which some already did). >> Also, there's an assumption that resource_copy_region works regardless >> of bind flags (at least for texture targets, actually might also need to >> work for buffers for "modern" drivers in the future not sure yet), hence >> there are no longer any PIPE_BIND_BLIT flags (which were quite magic to >> begin with, since a lot of the code could end up with a quad blit which >> really wants RENDER_TARGET/SAMPLER_VIEW bind flags instead). >> It is possible some of the drivers implementation are a bit suboptimal >> now, as they still use surfaces internally for easier migration (svga, >> r300g, nouveau might particularly benefit from some cleanup). >> If a driver implements this just with util_resource_copy_region, it is >> possible there are performance regressions, since some (certainly not >> all) state trackers used a quad blitter instead if this wasn't available. >> The u_blit code still uses a pipe_surface as destination, which should >> probably be changed at some point too but the change was already big >> enough imho. >> >> Historically, blits had to operate on surfaces IIRC since there actually >> were surfaces in gallium not backed by a pipe_resource (then >> pipe_texture) but those are gone. So get_tex_surface() should actually >> be viewed as the analogous function to create_sampler_view() (and yes it >> will migrate to context too and probably renamed to something else), it >> creates a view of a resource (the pipe_surface) to be used as a render >> target (color or depth/stencil). >> >> The msaa changes are fairly minimal, there's a new context function to >> set the sample mask (all drivers have dummy implementations), plus some >> bits for sample to coverage etc. And a explicit resource_resolve >> function which is defined as the only way to resolve a multisampled >> resource, but so far no driver implements multisampling (and the mesa >> state tracker won't use it neither). >> >> Comments? > > I was worried overlapping blits for u_blitter were no longer allowed, > this is a requirement so please don't break that if you find its in > the way. </div></div>I was thinking about changing the u_blitter code (I don't particularly like that there is all different code to u_blit but doing pretty much the same), but I left this as is (and there are no plans to change u_blit code to not handle overlap). That said though I can't see why u_blitter code still needs to handle overlap. Unless I'm missing something overlap can no longer happen there, at least not in master where r300 is the only user of this. </blockquote><div> I recall that overlapping surface_copy blits were required by st/xorg. Since you said that the overlapping blits are no longer permitted, the corresponding code can be removed from u_blitter. -Marek </div></div>