[Mesa-dev] [PATCH] i965: Disallow fast blit paths for CopyTexImage with PixelTransfer ops

[Anuj Phogat]

On Tue, Sep 8, 2015 at 12:58 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> On Tue, Sep 08, 2015 at 12:33:05PM -0700, Anuj Phogat wrote:
>> On Sun, Sep 6, 2015 at 9:37 AM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
>> > glCopyTexImage behaves similarly to glReadPixels with respect to the
>> > pixel transfer operations. Therefore if any are set we cannot use the
>> > simply blit fast paths.
>> >
>> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
>> > Cc: Jason Ekstrand <jason.ekstrand at intel.com>
>> > Cc: Kenneth Graunke <kenneth at whitecape.org>
>> > ---
>> >  src/mesa/drivers/dri/i965/brw_blorp_blit.cpp | 4 ++++
>> >  src/mesa/drivers/dri/i965/intel_tex_copy.c   | 4 ++++
>> >  2 files changed, 8 insertions(+)
>> >
>> > diff --git a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
>> > index 205c905..ba11d3d 100644
>> > --- a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
>> > +++ b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
>> > @@ -215,6 +215,10 @@ brw_blorp_copytexsubimage(struct brw_context *brw,
>> >     struct intel_renderbuffer *src_irb = intel_renderbuffer(src_rb);
>> >     struct intel_texture_image *intel_image = intel_texture_image(dst_image);
>> >
>> > +   /* No pixel transfer operations (zoom, bias, mapping), just a blit */
>> > +   if (brw->ctx._ImageTransferState)
>> > +      return false;
>> > +
>> >     /* Sync up the state of window system buffers.  We need to do this before
>> >      * we go looking at the src renderbuffer's miptree.
>> >      */
>> > diff --git a/src/mesa/drivers/dri/i965/intel_tex_copy.c b/src/mesa/drivers/dri/i965/intel_tex_copy.c
>> > index 4d8c82e..ecdd052 100644
>> > --- a/src/mesa/drivers/dri/i965/intel_tex_copy.c
>> > +++ b/src/mesa/drivers/dri/i965/intel_tex_copy.c
>> > @@ -55,6 +55,10 @@ intel_copy_texsubimage(struct brw_context *brw,
>> >     const GLenum internalFormat = intelImage->base.Base.InternalFormat;
>> >     bool ret;
>> >
>> > +   /* No pixel transfer operations (zoom, bias, mapping), just a blit */
>> > +   if (brw->ctx._ImageTransferState)
>> > +      return false;
>> > +
>> I think we need a similar condition in copytexsubimage_using_blit_framebuffer()
>> called from _mesa_meta_CopyTexSubImage().
>
> Actually,  ImageTransferState doesn't encompass all the PixelTransfer
> operations, so a few more checks are required along all the blit paths,
> namely ctl->Pixel.Zoom[XY] != 1.f
>
> Those latter we don't need along the meta path as Kenneth pointed out,
> both meta (though the blit path will need to check for integer
> coordinates after the transform) and blorp can handle zoom.
Right. I meant to say that brw->ctx._ImageTransferState condition
added in this patch is also applicable in _mesa_meta_CopyTexSubImage().
It'll be nice to add that change in this patch.

>
> More work required. :|
> -Chris
>
> --
> Chris Wilson, Intel Open Source Technology Centre