[Mesa-dev] [PATCH 2/2] i965: Flip interpolateAtOffset's y offset when necessary.

[Jason Ekstrand]

On Fri, May 13, 2016 at 1:42 AM, Kenneth Graunke <kenneth at whitecape.org>
wrote:

> Fixes 5 dEQP-GLES31.functional.shaders.multisample_interpolation tests:
> - interpolate_at_offset.no_qualifiers.default_framebuffer
> - interpolate_at_offset.centroid_qualifier.default_framebuffer
> - interpolate_at_offset.sample_qualifier.default_framebuffer
> - interpolate_at_offset.at_sample_position.default_framebuffer
> - interpolate_at_offset.array_element.default_framebuffer
>
> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
> ---
>  src/mesa/drivers/dri/i965/brw_fs_nir.cpp | 8 ++++++--
>  src/mesa/drivers/dri/i965/brw_wm.c       | 3 ++-
>  2 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> index 4648c58..5890750 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> @@ -2871,9 +2871,12 @@ fs_visitor::nir_emit_fs_intrinsic(const fs_builder
> &bld,
>        case nir_intrinsic_interp_var_at_offset: {
>           nir_const_value *const_offset =
> nir_src_as_const_value(instr->src[0]);
>
> +         const bool flip = !wm_key->render_to_fbo;
> +
>           if (const_offset) {
>              unsigned off_x = MIN2((int)(const_offset->f32[0] * 16), 7) &
> 0xf;
> -            unsigned off_y = MIN2((int)(const_offset->f32[1] * 16), 7) &
> 0xf;
> +            unsigned off_y = MIN2((int)(const_offset->f32[1] * 16 *
> +                                        (flip ? -1 : 1)), 7) & 0xf;
>
>              emit_pixel_interpolater_send(bld,
>
> FS_OPCODE_INTERPOLATE_AT_SHARED_OFFSET,
> @@ -2889,7 +2892,8 @@ fs_visitor::nir_emit_fs_intrinsic(const fs_builder
> &bld,
>                 fs_reg temp = vgrf(glsl_type::float_type);
>                 bld.MUL(temp, offset(offset_src, bld, i),
> brw_imm_f(16.0f));
>                 fs_reg itemp = vgrf(glsl_type::int_type);
> -               bld.MOV(itemp, temp);  /* float to int */
> +               /* float to int */
> +               bld.MOV(itemp, (i == 1 && flip) ? negate(temp) : temp);
>
>                 /* Clamp the upper end of the range to +7/16.
>                  * ARB_gpu_shader5 requires that we support a maximum
> offset
> diff --git a/src/mesa/drivers/dri/i965/brw_wm.c
> b/src/mesa/drivers/dri/i965/brw_wm.c
> index ced9708..192e8e2 100644
> --- a/src/mesa/drivers/dri/i965/brw_wm.c
> +++ b/src/mesa/drivers/dri/i965/brw_wm.c
> @@ -511,7 +511,8 @@ brw_wm_populate_key(struct brw_context *brw, struct
> brw_wm_prog_key *key)
>        key->drawable_height = _mesa_geometric_height(ctx->DrawBuffer);
>     }
>
> -   if ((fp->program.Base.InputsRead & VARYING_BIT_POS) ||
> program_uses_dfdy) {
> +   if ((fp->program.Base.InputsRead & VARYING_BIT_POS) ||
> +       program_uses_dfdy || prog->nir->info.uses_interp_var_at_offset) {
>

It's kind of lame that we have to add something to nir_shader_info just for
optimistically setting the key.  :-(  I guess not that many shaders use
things that actually need render_to_fbo so it's best to not set it all the
time.  Thanks for fixing the key bit!

Reviewed-by: Jason Ekstrand <jason at jlekstrand.net>


>        key->render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
>     }
>
> --
> 2.8.2
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20160513/15f59165/attachment-0001.html>