[Mesa-dev] features.txt & EXT_debug_label extension

[Ian Romanick]

On 02/10/2017 02:56 AM, Eero Tamminen wrote:
> Hi,
> 
> On 09.02.2017 19:30, Ian Romanick wrote:
>> On 02/09/2017 05:19 PM, Eero Tamminen wrote:
>>> When checking GL errors for "Unturned" (Steam top-20 Unity3D based
>>> game), I noticed that it uses functions from extension unsupported by
>>> Mesa, and missing from "features.txt":
>>> https://www.khronos.org/registry/OpenGL/extensions/EXT/EXT_debug_label.txt
>>>
> 
> ---------------------------------
> New Procedures and Functions
> 
>     void LabelObjectEXT(enum type, uint object, sizei length,
>         const char *label);
>     void GetObjectLabelEXT(enum type, uint object, sizei bufSize,
>         sizei *length, char *label);
> ---------------------------------
> 
>>> Could it be added to "features.txt" file?
>>
>> I thought the functionality of that extension was folded into some other
>> ARB (or KHR) extension... GL_KHR_debug, maybe?
> 
> Yes, that has similar functionality, and Mesa already supports it:
> https://www.khronos.org/registry/OpenGL/extensions/KHR/KHR_debug.txt
> 
> Just with different function names:
> 
>     void ObjectLabel(enum identifier, uint name, sizei length,
>         const char *label);
> 
>     void GetObjectLabel(enum identifier, uint name, sizei bufSize,
>         sizei *length, char *label);
> 
> As fairly new & commonly used Unity3D game and Apitrace both support the
> EXT versions, I think it makes sense add aliases also for the EXT variants.

I checked both extensions, and they're not "just" aliases.  The EXT adds
a single function with an enum to select the kind of object.  The KHR
adds a function per kind of object.  It would be easy enough to add, but
it seems more valuable to suggest the developer use the more broadly
supported extension. :)

>> It's also not the sort of thing that an app should use in release mode.
> 
> That (free-to-play) game is still in early access phase.  Maybe it helps
> developer getting more useful feedback from more techical users. :-)
> 
> 
>     - Eero
> 
>>> PS. Apitrace already outputs those debug labels in the replay output,
>>> but I didn't check whether its GUI could also make use of them.