[Mesa-dev] [PATCH] i965: fix mask used to write to clip distance registers when gen>6

[Paul Berry]

On 13 June 2011 09:58, Eric Anholt <eric at anholt.net> wrote:
> On Sun, 12 Jun 2011 21:14:50 -0700, Paul Berry <stereotype441 at gmail.com> wrote:
>> In gen6 and above, clip distances 0-3 are written to message register
>> 3's xyzw components, and 4-7 to message register 4's xyzw components.
>> Therefore when when writing the clip distances we need to examine the
>> lower 2 bits of the clip distance index to see which component to
>> write to.
>>
>> emit_vertex_write() was examining the lower 3 bits, causing clip
>> distances 4-7 not to be written correctly.
>
> Reviewed-by: Eric Anholt <eric at anholt.net>
>
> Is this caught by any new testcase?  It's not a requirement, just
> thinking that since you were building testcases like this recently, it
> might be easy.
>

Yes, agreed.  It's caught by vs-clip-vertex-01.shader_test, which I
sent to the piglit list earlier that day.  The patch hasn't landed
yet.