On Thu, Mar 27, 2014 at 12:16 PM, Ilia Mirkin <imir...@alum.mit.edu> wrote: > On Thu, Mar 27, 2014 at 11:35 AM, Jose Fonseca <jfons...@vmware.com> wrote: >> >> >> ----- Original Message ----- >>> On Wed, Mar 26, 2014 at 4:30 AM, Roland Scheidegger <srol...@vmware.com> >>> wrote: >>> > Am 26.03.2014 03:29, schrieb Marek Olšák: >>> >> My reasoning was that it would be better to specify a raw clear value >>> >> and clear value size for buffers, which are always untyped, and >>> >> pipe_color_union for textures, which are always typed, so that drivers >>> >> can easily implement the texture clearing on top of >>> >> pipe_context::clear. >>> >> >>> >> I also suggested that clear_render_target and clear_depth_stencil >>> >> should be removed in favor of a new function clear_texture(pipe, >>> >> resource, level, box, pipe_color_union). For depth-stencil, we can >>> >> assume that the first component of the clear color is a floating-point >>> >> depth value and the second component is an unsigned integer stencil >>> >> value. >>> > This could not clear only depth or stencil, though. >>> > Clear is just a mess why couldn't the apis agree a bit more what is >>> > useful... >>> > So d3d10 can only clear render target / depth stencil views, meaning >>> > your resrouces need the bind_render_target flag (not that drivers >>> > actually usually enforce this for rendering since it breaks mesa state >>> > tracker in a couple of places due to this being not required in general >>> > and hard to guess in GL). You cannot clear only parts (or rather, you >>> > can clear individual layers and such by creating a different view, but >>> > not specify coords). You can however clear only depth or stencil. >>> > And you cannot clear buffers (well you can if you make them render >>> > target bindable but this has severe limitations and isn't something >>> > you'd do just so you can clear them). >>> > GL OTOH doesn't require the resources to be renderable for clearing to >>> > work, doesn't allow to clear only depth/stencil but does allow a box. >>> > There's also another problem with the proposed parameters for d3d10, the >>> > format of the resource could be different to that you'd actually want to >>> > use for clearing (for typeless resources). >>> >>> Adding the format parameter is not a problem. It would also allow >>> depth-only or stencil-clear by setting Z24X8 or X24S8, respectively. >>> >>> Regarding non-renderable textures, well, RGB9_E5 is the only >>> non-renderable GL format on Radeon and we could easily clear that as >>> R32_UINT. Radeon drivers already change texture formats to support >>> fully-accelerated resource_copy_region and they will do so for >>> clearing as well. You can always use a software fallback if you have >>> no other option. >>> >>> Some of the GL 4.x stuff will be a bigger mess, and there are also fun >>> things like GL_ARB_bindless_texture. >> >> Having a clear_resource, with all necessary parameters so it can superceed >> clear_render/depth_stencil view, seems a sensible thing to do FWIW. > > Just to clarify -- is this a vote against my current implementation of > ARB_clear_buffer_object acceleration (which adds a ->clear_buffer > call), or a comment on how you'd like to see ARB_clear_texture > acceleration implemented?
I haven't heard back on this, so I'm assuming that everyone is fine with my proposed patches as-is. I have a R-b from Marek for the generic bits, so unless I hear otherwise by tonight, I'll be pushing that out. > > If the latter, I'm concerned that there will be drivers that can clear > RT's but not random textures. This shouldn't be an issue for > nv50/nvc0, but I'm much less familiar with what else is out there. > FWIW, the way that'd be done on nv50/nvc0 is by cheating -- there are > actually a bunch of formats that can be used for texturing but not > rendering. But the clear mechanism is just a glorified memset, so we > can fake the formats as long as they're the right number of bytes. > > -ilia _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
