[Impeller] Lines with stroke width < 1 physical pixel are too thick. #144313
Description
Steps to reproduce
It looks like there is a cap at strokeWidth with Impeller. I tested it on iOS 17 device and simulator. I see the same effects with:
_mPaint.strokeWidth = 0.05;
_mPaint.style = PaintingStyle.stroke;
like with:
_mPaint.strokeWidth = 0.01;
_mPaint.style = PaintingStyle.stroke;
For me it looks like a 0.05 is a minimum value, however in Skia I don't see this limitation and I can draw really thin lines. Thin lines are important for effects like a school's paper cards etc.
Expected results
Thin lines should be rendered without artificial cap, like with Skia.
Actual results
There is a IMHO high minimum limit for strokeWidth.
Code sample
_mPaint.strokeWidth = 0.05;
_mPaint.style = PaintingStyle.stroke;
Screenshots or Video
No response
Logs
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Flutter Doctor output
Doctor output
[✓] Flutter (Channel stable, 3.16.9, on macOS 14.3.1 23D60 darwin-x64, locale pl-PL)
• Flutter version 3.16.9 on channel stable at /Users/patryk/Programowanie/sdk/flutter
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• iPhone SE (mobile) • 00008030-001254281AD2402E • ios • iOS 17.3 21D50
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Important issues not at the top of the work listUI glitches reported at the engine/skia or impeller rendering levelImpeller rendering backend issues and features requestsflutter/engine related. See also e: labels.Found to occur in 3.19Found to occur in 3.20The issue has been confirmed reproducible and is ready to work onIssue is closed as already fixed in a newer versionOwned by Engine teamTriaged by Engine team