GL framebuffer fetch behavior

[ella]

On 2025-04-24 07:13, Iago Toral wrote:
> For v3d yzw would be 0,0,1.
> 

It's worth noting that in our framebuffer fetch implementation we
override unused components with undefs.

Ella

> Iago
> 
> El mié, 23-04-2025 a las 12:24 -0400, Mike Blumenkrantz escribió:
>> Hi,
>> 
>> An issue recently came up in the GL working group: what is the
>> robustness behavior of framebuffer fetch? For example, if a
>> framebuffer attachment format is R8_UNORM, what are the YZW
>> components which get read back?
>> 
>> If people from all the drivers (besides panfrost) which support this
>> extension could reply with the expected behavior on their hardware,
>> that would be helpful.
>> 
>> 
>> Thanks,
>> Mike