[Windows 11/SDL_Render] Pixel are wrong in FULLSCREEN only on High-DPI screen when hint SDL_WINDOWS_DPI_AWARENESS is set

[l-t-m-f]

Hello guys,

I'm going to post an example later but I noticed on all my projects with the SDL_Render API, if I toggled full screen, the pixels are looking weird and smaller than they should on high-DPI screen. I am noticing this on a new laptop with a 3840x2400 screen which needs to run applications are 200% scaling otherwise everything is microscopic.

I hadn't noticed before because I'm working on a game where the pixel art is very small and thus it was merely making it "fuzzy" (like if there were a bi-linear filter over everything). However, I was working on a new project tonight with a basic 1-bit style, and it became particularly egregious.

I would post a screenshot, but the weirdest thing happens... When I take the screenshot, the pixels in the image are back to normal.

Let me know if I can provide more info while in the meantime I prepare some example.

Also, I noticed that the hint for SDL_Render "SDL_WINDOWS_DPI_AWARENESS" isn't needed now?
I remember having to use it before on this display. I toggled it on or off and see no difference in the main branch.

[l-t-m-f]

Ok, I figured out the problem while coding the minimal reproduce. I had DPI awareness On when it should have been/and I thought it were set to Off. The reason is bellow...

Both the following set the hint to true, is this intended?
SDL_SetHint ("SDL_WINDOWS_DPI_AWARENESS", "0");
SDL_SetHint ("SDL_WINDOWS_DPI_AWARENESS", "1");

I was doing something like this in my framework:
if (params->b_is_DPI_aware == false)
{
SDL_SetHint ("SDL_WINDOWS_DPI_AWARENESS", "0");
}
else
{
SDL_SetHint ("SDL_WINDOWS_DPI_AWARENESS", "1");
}

I just won't call the hint at all now on the false case.

I noticed that if the hint is on and fullscreen is toggled on, pixel will be distorted. Therefore I think there is still an issue with the hint when fullscreen is active, which is why I keep this issue open for now.

[l-t-m-f]

I made a search in the history of the commits around that hint but failed to see anything significant.
So I made an example if you want to test the problem: https://pastecode.io/s/5v010ixg
It uses the following art:

Disable the line SDL_SetRenderLogicalPresentation(r, 480, 480, SDL_LOGICAL_PRESENTATION_INTEGER_SCALE); and the problem will appear different.

Which makes the problem very stark and apparent on my end.
If you want to try on a High DPI display on Windows 11.

[slime73]

Which version of SDL are you using?

[l-t-m-f]

I'm using the project's main. I tried checking out a few commit backs and saw no difference.