Font rendering is different in version 11.1.0-beta1 on Windows

[DavidZidar]

Describe the bug

I tried updating my application to the beta and noticed that fonts are slightly smaller and blurrier than before.

As there is no mention of this change in the release notes so I wonder if it's intentional or a mistake?

Here's how a section of my app looks with v11.0.10 (nice and clear):

And here's what it looks with v11.1.0-beta1 (blurry and too small):

To Reproduce

Update to v11.1.0-beta1.

Expected behavior

The font rendering should be like before, or if it's intentional it should be in the release notes and there should be info on how to make adjustments if possible.

Avalonia version

11.1.0-beta1

OS

Windows

Additional context

No response

[timunie]

Please file a minimum sample using your font to double-check on our side

[DavidZidar]

@timunie It's the default font. But this also happens with a custom font I have so I assume it affects all fonts.

[DavidZidar]

I reproduced it using dotnet new avalonia.app and then updating to 11.1.0-beta1

With 11.0.10:

With 11.1.0-beta1:

[Gillibald]

Second image has no ClearType enabled

[DavidZidar]

Just to be clear, the only change I made was the version number of the Avalonia packages.

[rabbitism]

similar
#14711

[timunie]

Yeah seems to be a duplicate of #14711 .

@Gillibald I'll leave it to you if you want to close that issue in favor of the other one

[DavidZidar]

Is it actually a duplicate? I opened a separate issue because I am not seeing a difference in the font rendering in the other screenshot, just different boldness. But maybe my eyes are deceiving me.

[Gillibald]

Such issue reports are not helping. I need a minimal repro I can run as is without building some full blown up application.

[rabbitism]

https://github.com/rabbitism/FontDiffIssue
https://github.com/rabbitism/AvaloniaIssueRepro/tree/main/FontRenderIssue
Here is the repro, run both projects and compare closely.

[DavidZidar]

Such issue reports are not helping. I need a minimal repro I can run as is without building some full blown up application.

Your own hello world template reproduces the issue, I don't see the problem.

[maxkatz6]

Looks like ClearType doesn't work for some reason.

[BobbyCannon]

Tested with 11.1.0-beta2 in the repo example. It's still fuzzy.

https://github.com/rabbitism/AvaloniaIssueRepro/tree/main/FontRenderIssue

Also it's easy to see if you just open the Avalonio DevTools

[grokys]

The problem here is related to Skia(Sharp):

• https://issues.skia.org/issues/327877721 causes rendering artifact for Sliders, ProgressBar and similar controls (Slider with custom style leaves spots outside of its bounds #14270)
• The only way to fix those is to force an extra intermediate layer for rendering via SKCanvas.SaveLayer (Reworked the way we are clipping dirty rects with CompositionTarget #14806)
• SKCanvas.SaveLayer disables subpixel rendering
• No subpixel rendering results in bad-looking fonts

This API is required to make sub pixel rendering work with layers: https://api.skia.org/structSkCanvas_1_1SaveLayerRec.html

One can currently set CompositionOptions.UseSaveLayerRootClip = false to disable the extra intermediate layer and get font rendering back to normal - at the expense of some rendering artifacts in some situations.

My feeling is that CompositionOptions.UseSaveLayerRootClip = false should be the default for now, until we can fix the problem at its source.