[Mesa-dev] [Mesa-stable] [PATCH] mesa/main: fix version/extension checks in _mesa_ClampColor

[Nicolai Hähnle]

On 12.01.2017 17:57, Ilia Mirkin wrote:
> On Thu, Jan 12, 2017 at 11:46 AM, Nicolai Hähnle <nhaehnle at gmail.com> wrote:
>> On 12.01.2017 17:41, Ilia Mirkin wrote:
>>>
>>> On Thu, Jan 12, 2017 at 11:39 AM, Emil Velikov <emil.l.velikov at gmail.com>
>>> wrote:
>>>>
>>>> On 12 January 2017 at 09:55, Nicolai Hähnle <nhaehnle at gmail.com> wrote:
>>>>>
>>>>> From: Nicolai Hähnle <nicolai.haehnle at amd.com>
>>>>>
>>>>> Add a proper check for feature support, and raise an invalid enum for
>>>>> GL_CLAMP_VERTEX/FRAGMENT_COLOR unconditionally in core profiles, since
>>>>> those enums were explicitly removed after the extension was promoted
>>>>> to core functionality (not in the profile sense) with OpenGL 3.0.
>>>>>
>>>> Wouldn't it be better to simply not advertise the extension for Core
>>>> profiles ?
>>>
>>>
>>> I'm fine with either approach FWIW. My initial comments were based on
>>> the theory that the ext enabled clamping in core contexts, but that
>>> doesn't sound like it's the case.
>>>
>>> Could be more straightforward to just flip the ext to be GLL instead.
>>
>>
>> I'm fine with that.
>>
>> I should point out though that this patch as-is makes some sense regardless,
>> because the check for feature support was actually totally missing (think GL
>> < 3.0, no support for float buffers -- that would have let one of the enums
>> through).
>
> Perhaps make the ext GLL and make this function check
> _mesa_has_ARB_color_buffer_float() which should DTRT?

Actually, _mesa_ClampColor would have to check ARB_color_buffer_float 
directly, because it needs to be supported in core contexts.

Also, this requires the Intel driver to set ARB_color_buffer_float 
unconditionally, but then there's a bunch of meta code that might fail. 
This is surprisingly messy :/

Nicolai