The upcoming GTK 4.23.1 development release is introducing a new feature called Snapping, which should enhance the experience when dealing with fractional scaling on today's high resolution displays.

GTK's snapping feature adjusts the placement of rectangles when drawing to ensure they align with the pixel grid and do not cover half a pixel. This snapping to ensure alignment with the pixel grid is important with fractional scaling. Developers enabling snapping can ensure that any game sprites are correctly aligned and also being useful for applications displaying images and wanting to ensure the pixels match 1:1 between the image and displayed output. For redirected drawing such as game emulators and VM viewers and the like, snapping can prove useful too.

Snapping isn't enabled by default for all GTK apps though since automatic snapping could cause smoothness issues during slow animations. Developers wanting to learn more about this GTK snapping feature can do so via the GTK blog.