[Mesa-dev] GLX extension for vendor name lookup in libglvnd

[Kyle Brenneman]

On 03/14/2016 11:43 AM, Martin Peres wrote:
> On 14/03/16 19:16, Kyle Brenneman wrote:
>>
>> On 03/11/2016 05:25 PM, Martin Peres wrote:
>>>
>>>
>>> On 10/03/16 20:07, Adam Jackson wrote:
>>>> On Thu, 2016-03-10 at 10:53 -0700, Kyle Brenneman wrote:
>>>>> On 03/10/2016 10:47 AM, Martin Peres wrote:
>>>>>> That could be a hacky way of handling the case where multiple 3D
>>>>>> drivers could be used to drive the same GPU. This may be 
>>>>>> necessary in
>>>>>> the future if two mesa drivers support the same GPU but one is
>>>>>> considered better than the other. We can also imagine a case where a
>>>>>> proprietary driver would need to be co-installable with an open 
>>>>>> source
>>>>>> one and would still use the same DDX. Isn't that what AMD is 
>>>>>> going to
>>>>>> do soon? Did anyone think about this case?
>>>>> That case is the reason for allowing multiple vendor names. For a 
>>>>> case
>>>>> like AMD's driver, it would hand back two names. The order would 
>>>>> be up
>>>>> to the driver implementation, but I would guess that it would list 
>>>>> the
>>>>> proprietary driver first and the open source driver second. If the
>>>>> proprietary one is installed, then the client would use it, and if 
>>>>> not,
>>>>> the client would use the open source one.
>>>
>>> Very good! That could be worth mentioning in the spec. To make it
>>> clear that it is the intended goal and to help implementers understand
>>> the logic behind this proposal.
>> That's what I meant to convey with the description of multiple
>> client-side drivers that work with the same server-side driver. But if
>> that wasn't clear I can add a more specific example. Would something
>> like this help?
>>
>>
>>      For example, some vendors may have both a proprietary client-side
>>      vendor library and an open source vendor library that work with the
>>      same server-side driver. In that case, the server would return the
>>      names for both of the vendor libraries. The client would then be 
>> able
>>      to select one of those vendor libraries, depending on which of 
>> them is
>>      installed.
>
> This is definitely a nice addition, however, I propose to reword it to 
> add information about priorities:
>
>
>   For example, some vendors may have both a proprietary client-side
>   vendor library and an open source vendor library that work with the
>   same server-side driver. In that case, the server would return the
>   names for both of the vendor libraries, in the order of preference.
>   The client would then try to open them sequentially and select the
>   first one that is present and got loaded successfully.
>
> How does this sound?
Issue #3 addresses the question of how the vendor names are ordered. 
Instead of duplicating the description, maybe change the last sentence 
to reference that issue:

"The client would then try loading each vendor library as described 
below in Issue 3."