[Mesa-dev] [PATCH] llvmpipe: Obey back writemask.

[Brian Paul]

On 10/30/2012 01:48 PM, jfonseca at vmware.com wrote:
> From: José Fonseca<jose.r.fonseca at gmail.com>
>
> Tested with a modified glean tstencil2 test.
> ---
>   src/gallium/drivers/llvmpipe/lp_bld_depth.c |   10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/src/gallium/drivers/llvmpipe/lp_bld_depth.c b/src/gallium/drivers/llvmpipe/lp_bld_depth.c
> index 8efa75c..5c3715a 100644
> --- a/src/gallium/drivers/llvmpipe/lp_bld_depth.c
> +++ b/src/gallium/drivers/llvmpipe/lp_bld_depth.c
> @@ -273,11 +273,17 @@ lp_build_stencil_op(struct lp_build_context *bld,
>         res = lp_build_select(bld, front_facing, res, back_res);
>      }
>
> -   /* XXX what about the back-face writemask? */
> -   if (stencil[0].writemask != 0xff) {
> +   if (stencil[0].writemask != 0xff ||
> +       (stencil[1].enabled&&  front_facing != NULL&&  stencil[1].writemask != 0xff)) {
>         /* mask&= stencil[0].writemask */
>         LLVMValueRef writemask = lp_build_const_int_vec(bld->gallivm, bld->type,
>                                                         stencil[0].writemask);
> +      if (stencil[1].enabled&&  stencil[1].writemask != stencil[0].writemask&&  front_facing != NULL) {
> +         LLVMValueRef back_writemask = lp_build_const_int_vec(bld->gallivm, bld->type,
> +                                                         stencil[1].writemask);
> +         writemask = lp_build_select(bld, front_facing, writemask, back_writemask);
> +      }
> +
>         mask = LLVMBuildAnd(builder, mask, writemask, "");
>         /* res = (res&  mask) | (stencilVals&  ~mask) */
>         res = lp_build_select_bitwise(bld, mask, res, stencilVals);


Reviewed-by: Brian Paul <brianp at vmware.com>

Does this fix https://bugs.freedesktop.org/show_bug.cgi?id=41787 ?

If so, maybe make note of that in the commit message.

Candidate for stable branches?

-Brian