Text gets blurry when resizing the viewport with the `canvas_items` stretch mode

[Kyrio]

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Bugsquad note: This issue has been confirmed several times already. No need to confirm it further.

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Tested versions

• Reproducible in: v4.2.1.stable.official [b09f793]
• Also reproducible in: v4.1.3

System information

Godot v4.2.1.stable - Windows 10.0.19045 - GLES3 (Compatibility) - NVIDIA GeForce GTX 950M (NVIDIA; 31.0.15.3118) - Intel(R) Core(TM) i5-6300HQ CPU @ 2.30GHz (4 Threads)

Issue description

One of the main advantages of the canvas_items stretch mode (née 2d) is that it scales the UI automatically while keeping the shapes and fonts crisp at any window size. It's particularly useful when you want to keep the same size ratios in your UI regardless of resolution. This is illustrated by the attached project, which I've created for both Godot 3 and Godot 4.

Here are two screenshots taken on Godot 3 (view them at 100% size to get a better idea):

• Godot 3.5.3: project run at its base viewport size (1024x576)
• Godot 3.5.3: same project when run fullscreen (1366x768)

The text remains crisp in Godot 3 when the viewport size increases or decreases.

However, in Godot 4, the behavior is different and fonts get slightly blurry at any resolution other than the viewport size defined in the settings.

• Godot 4.2.1: project run at its base viewport size (1024x576)
• Godot 4.2.1: same project when run fullscreen (1366x768)

The same behavior can be observed when resizing to a smaller viewport size, with blur being particularly noticeable.

• Godot 3.5.3:
• Godot 4.2.1:

Steps to reproduce

1. Load the Godot 4 MRP
2. Run the project, the default viewport size is 1024x576
3. Resize the window or expand it, or set the project to run fullscreen
4. Notice that the text is crisp at the base resolution, but blurry at smaller/larger resolutions
5. You can compare with the Godot 3 project where fonts remain crisp regardless

Minimal reproduction project (MRP)

• Godot 4 project: StretchTest_Godot4.zip
• Godot 3 project for comparison: StretchTest_Godot3.zip

[Calinou]

For reference, I was able to confirm this on my end. It seems to be related to how font oversampling works, possibly rounding in an incorrect manner. Changing font hinting settings in the import dock doesn't resolve the issue.

cc @bruvzg

[conde2]

I'm having the same problem and can confirm it:

v4.2.1.stable.mono.official [b09f793]

Here is a Minimal reproduction project (MRP)

Bug.zip

[Calinou]

@conde2 This is an unrelated issue: #54030

[conde2]

@Calinou, maybe its related to both, I realized that the entire UI gets blurry too, is it supposed to happen?

Just try with my MRP, just by changing the resolution the UI is all blurry

[conde2]

Ok after some research I found a topic in godot forum with the same problem I had:

https://forum.godotengine.org/t/blury-text-on-label/42452/2

After changing this settings I was able to get my game running crystal clear, not blurry interface and text
For anyone having the same problem, here is the settings I had to change:

theme/default_font_hinting=2
theme/default_font_multichannel_signed_distance_field=true
theme/lcd_subpixel_layout=0

[Calinou]

Ok after some research I found a topic in godot forum with the same problem I had:

The issue you're encountering is different from the issue reported here. When zooming in the 2D editor, fonts are not re-rasterized as this could be extremely slow at high zoom levels. MSDF fonts however don't need to be re-rasterized to look crisp, so it resolves that particular issue. However, MSDF fonts don't address the problem outlined here for non-MSDF fonts (they are supposed to be perfectly crisp at 100% scaling).

For anyone having the same problem, here is the settings I had to change:

Note that when you enable MSDF font rendering, font hinting and LCD subpixel layout settings are ignored, so you don't need to change these.

[conde2]

I understand, Im using the default fonts from godot 4.2 so It's definitely other problem. Should I open a new issue then?

Also I just want to add to the topic that the blurry was not in the editor it was in the game itself and after changing this settings the GAME become crystal clear.
So maybe this settings are affecting the game and shouldn't? For example in the GUI settings if you change the tooltip delay it also changes the in game tooltip delay.

If this is the way it's supposed to be I believe this option should be enabled by default or stated in the docs more clearly.

[Calinou]

I understand, Im using the default fonts from godot 4.2 so It's definitely other problem. Should I open a new issue then?

This was already talked about a while ago, and was considered to not be a bug as we can't resolve it without excessive performance overhead: #69711

On top of that, it could be argued that re-rasterizing DynamicFonts when you zoom in the editor would be misleading as this behavior wouldn't occur when running the project and zooming with a Camera2D.

So maybe this settings are affecting the game and shouldn't? For example in the GUI settings if you change the tooltip delay it also changes the in game tooltip delay.

MSDF fonts can improve font appearance in the running project if you change Camera2D zoom. This is expected behavior, since it's how MSDF fonts work: they are rasterized once, and a shader is used to interpolate smooth curves from the signed distance field data.

If this is the way it's supposed to be I believe this option should be enabled by default or stated in the docs more clearly.

MSDF fonts have several limitations outlined in the documentation and don't look great at small sizes, so we can't make them the default.

[hhyyrylainen]

I have an issue with only tooltips becoming blurry. All other text and custom tooltips that we have implemented in Thrive (but made to look basically like the inbuilt ones) look fine when scaled and even their borders are non-blurry. So only inbuilt tooltips experience blurriness problems in text and their borders also look pixelated so it is not only the text that is impacted.

Should I open a separate issue about that? I couldn't find any issues specifically about blurry tooltips.