[Mesa-dev] [PATCH 2/2] Make envvars set to zero actually be false

[Matt Turner]

On Thu, Oct 11, 2012 at 6:08 PM, Dave Airlie <airlied at gmail.com> wrote:
> On Thu, Oct 11, 2012 at 8:53 PM, Matt Turner <mattst88 at gmail.com> wrote:
>> On Thu, Oct 11, 2012 at 2:12 PM, Dave Airlie <airlied at gmail.com> wrote:
>>>> Previously, LIBGL_ALWAYS_SOFTWARE=0 glxgears would still run swrast.
>>>> This is not what people expect.
>>>
>>> Is it documented either way, its kinda like ifdef vs if in C, I
>>> generally for this sort of thing except ifdef behaviour.
>>>
>>> Dave.
>>
>> envvars.html says
>>
>> <li>LIBGL_ALWAYS_INDIRECT - forces an indirect rendering context/connection.
>> <li>LIBGL_ALWAYS_SOFTWARE - if set, always use software rendering
>>
>> which I should update as a part of this patch.
>
> From reading your last two mails, I think do nothing is a fine
> solution. Why change it if only 10 out 10517 hits tried to use it
> wrong,
>
> its documented, changing it also means we have two documented
> behaviours for different releases of mesa.
>
> Dave.

The reason I came to this was that I wanted to compare some program's
execution using swrast and a hardware driver, and changing
LIBGL_ALWAYS_SOFTWARE=1 to =0 seems very much like it should *not*
still use software. It's counter-intuitive, and it's hard to
understand why LIBGL_ALWAYS_SOFTWARE set to false should use software
renderering.