I made a game and engine in D that's a cross between Superliminal and Viewfinder, and you can play the demo now

[Hipreme]

On Wednesday, 2 April 2025 at 09:37:44 UTC, Lewis wrote:
> On Friday, 28 March 2025 at 22:44:56 UTC, Hipreme wrote:
>> On Thursday, 27 March 2025 at 06:27:19 UTC, Lewis wrote:
>>> On Thursday, 6 March 2025 at 15:35:19 UTC, Element Green 
>>> wrote:
>>>> [...]
>>>
>>> For anyone coming to this later, the Proton flickering bug 
>>> should be fixed now :)
>>
>> That's interesting! How did you fix it?
>
> It turned out to be debug code in a shader that was 
> accidentally getting compiled in. The debug code checked a 
> constant buffer value indicating whether the level editor was 
> active, and if so it disabled the paint-in effect (and just 
> made everything fully painted in).
>
> In release, we don't bother ever setting this 
> isLevelEditorActive parameter, since the editor is compiled out 
> of the release build and thus unusable. But this bad debug code 
> was still using the parameter. And since nobody was setting the 
> value, the value was unspecified. On most GPUs/drivers, it 
> seemed to be defaulting to 0, aka no editor, so it worked out 
> by accident. But when using Proton, for whatever reason, it 
> didn't default to 0 and instead had random unspecified values, 
> so it flickered between on and off.
>
> A classic case of a bug that was occurring on all machines, but 
> only actually showing observable symptoms on a select few. The 
> good news is that I installed a Ubuntu dual boot in order to 
> track this down, so I can now just test on Proton as a matter 
> of course when pushing out updates.

Oh that makes a lot of sense! There exists a lot of issues in 
regard of unused shader variables, so, it is a must check every 
time. On OpenGL, for example, if a variable is unused, it might 
get removed from the shader and trying to set it somewhere will 
cause issues. Uninitialized is almost on the same ground of 
undefined behavior