GTK 4.12 Released With Many Vulkan Backend Improvements

[equeim]

Whether you set font size via DPI, or scaling percent, or whatever other means, the problem is the same: you are making the font itself bigger, while everything else (the area the font is contained in, buttons, titlebars, etc) is the same size*.

*there are some exceptions, e.g. Firefox is specifically designed to interpret an increased font size setting as setting an overall fractional scale, so the entire interface will scale, button sizes and all, rather than just the fonts themselves.

The problem with scaling other UI elements is that even if they are scalable (e.g. SVG icons) they are created with intention of being drawn to pixels and have discrete dimensions that align to pixel grid at 1.0 scale. So when you scale them with fractional factors you will notice they don't look as good as they should.This won't be that nociable at high scale factors, but when you get close to 1 it is obvious. For example this is Plasma's shutdown button at 1.0 and 1.25 scale:

Screenshot_20230809_020900.png
Screenshot_20230809_020800.png

Of course not scaling them at all is not good either. The only perfect solution to this problem is to dispose of all low-PPI displays and buy ones that have at least 192 PPI (4K resolution or higher). That's what Apple did and what smartphones have been doing for decades.

[QwertyChouskie]

The problem with scaling other UI elements is that even if they are scalable (e.g. SVG icons) they are created with intention of being drawn to pixels and have discrete dimensions that align to pixel grid at 1.0 scale. So when you scale them with fractional factors you will notice they don't look as good as they should.This won't be that nociable at high scale factors, but when you get close to 1 it is obvious. For example this is Plasma's shutdown button at 1.0 and 1.25 scale:

Screenshot_20230809_020900.png
Screenshot_20230809_020800.png

Of course not scaling them at all is not good either. The only perfect solution to this problem is to dispose of all low-PPI displays and buy ones that have at least 192 PPI (4K resolution or higher). That's what Apple did and what smartphones have been doing for decades.

There's also rendering tricks that can/should be applied to help in these situations. For example, if you have a 20px square with 1px borders, at 125% fractional scale, you increase the size of the square to 25px, but you still render the border as 1px; at 175% fractional scale, you would make the square 35px wide with 2px borders. This avoids the blurry borders shown in your screenshot.

That being said, if you only need around 125% scaling (e.g. 14" 1080p), increasing just the font scale is often the way to go. You generally avoid weird scaling of icons/etc, fonts are readable, and as a bonus you have more screen real estate than you would with 125% fractional scaling of everything.

[equeim]

There's also rendering tricks that cab/should be applied to help in these situations. For example, if you have a 20px square with 1px borders, at 125% fractional scale, you increase the size of the square to 25px, but you still render the border as 1px; at 175% fractional scale, you would make the square 35px wide with 2px borders. This avoids the blurry borders shown in your screenshot.

That being said, if you only need around 125% scaling (e.g. 14" 1080p), increasing just the font scale is often the way to go. You generally avoid weird scaling of icons/etc, fonts are readable, and as a bonus you have more screen real estate than you would with 125% fractional scaling of everything.

That can work if toolkit knows what it's drawing, but what about icons or other arbitrary svgs?
That being said, I also enabled 125% scaling in Windows and it looks much better than in Plasma (especially in UWP apps).