Question: Are differences between UWP/WinUI and WPF path rendering expected?

[nCastle1]

I'm currently working on an app with UIs for both UWP and WPF (long story) and would like to use Paths for vector icons.

Based on my reading of path markup syntax doc the behavior should be the same as WPF.

In practice, I see very different results; of the vector icons I've tried, about half of them render properly and half don't.

Example:

WPF	UWP

Path: M 8.023 1.023 l -8 4.5 8 4.5 8-4.5 z m -5.96 4.5 l 5.96 -3.352 5.96 3.352 -5.96 3.353 z m 13.96 3 l -8 4.5 -8 -4.5 1.02 -.573 6.98 3.926 6.98 -3.926 z m -8 6.353 l 6.98 -3.926 1.02 .573 -7.914 4.452 a .175 .175 0 0 1 -.171 0 L .023 11.523 l 1.02-.573 z

Is this a known limitation of UWP/WinUI or is it a bug?

Solution contains a working example demonstrating the same path on UWP, WInUI 3, and WPF:

PathRepro.zip

In my research I turned up the following issues, but I don't think they answer my question:

• PathIconSource claims to support sharing but throws exception (AKA shared Geometry issue) #827
• An Iconic Disaster #1494
• Reusing XAML Path Style does not work #1874

[StephenLPeters]

@codendone fyi

[robloo]

Looks like a bug. Path rendering should be the same between WPF and UWP.

[codendone]

Correct, rendering should be the same, so this looks like a bug.

[dotMorten]

Here are some more examples. I think the first one demonstrates the issue in the simplest way (the inner triangle is rendering wrong not correctly performing the move). I believe they are all the same little bug.

Triangle:
M31.345 29H1.655L16.5 1.96zm-28-1h26.31L16.5 4.04z
WPF:
WinUI :

X Icon
M21.678 4H11.322L4 11.322v10.356L11.322 29h10.356L29 21.678V11.322zm1.47 18.157l-.99.99L16.5 17.49l-5.657 5.657-.99-.99L15.51 16.5l-5.657-5.657.99-.99L16.5 15.51l5.657-5.657.99.99L17.49 16.5z
WinUI:
WPF:

Web
M16.5 2.2a14.3 14.3 0 1 0 14.3 14.3A14.3 14.3 0 0 0 16.5 2.2zM3.225 17h4.99a22.74 22.74 0 0 0 .901 6H4.903a13.218 13.218 0 0 1-1.678-6zM17 9V3.246c2.29.285 4.295 2.492 5.523 5.754zm5.862 1a21.999 21.999 0 0 1 .924 6H17v-6zM16 3.246V9h-5.523C11.705 5.738 13.709 3.531 16 3.246zM16 10v6H9.214a21.999 21.999 0 0 1 .924-6zm-7.785 6h-4.99a13.218 13.218 0 0 1 1.678-6h4.213a22.74 22.74 0 0 0-.901 6zm1 1H16v6h-5.862a21.999 21.999 0 0 1-.924-6zM16 24v5.754c-2.29-.285-4.295-2.492-5.523-5.754zm1 5.754V24h5.523c-1.228 3.262-3.232 5.469-5.523 5.754zM17 23v-6h6.786a21.999 21.999 0 0 1-.924 6zm7.785-6h4.99a13.218 13.218 0 0 1-1.678 6h-4.213a22.74 22.74 0 0 0 .901-6zm0-1a22.74 22.74 0 0 0-.901-6h4.213a13.218 13.218 0 0 1 1.678 6zm2.696-7h-3.928a12.578 12.578 0 0 0-3.329-5.261A13.316 13.316 0 0 1 27.481 9zM12.776 3.739A12.578 12.578 0 0 0 9.446 9H5.52a13.316 13.316 0 0 1 7.257-5.261zM5.519 24h3.928a12.578 12.578 0 0 0 3.329 5.261A13.316 13.316 0 0 1 5.519 24zm14.705 5.261A12.578 12.578 0 0 0 23.554 24h3.927a13.316 13.316 0 0 1-7.257 5.261z
WinUI:
WPF:

Table
M2 5v22h28V5zm6 21H3v-4h5zm0-5H3v-4h5zm0-5H3v-4h5zm10 10H9v-4h9zm0-5H9v-4h9zm0-5H9v-4h9zm11 10H19v-4h10zm0-5H19v-4h10zm0-5H19v-4h10zm0-5H3V6h26z
WinUI:
WPF: