StrokeDashArray does not behave the same on all platforms

[agneszitte]

Current behavior

StrokeDashArray does not behave the same on all platforms

• Windows
  
• WASM
  
• Desktop
  
• Android
  
• iOS
  

Expected behavior

StrokeDashArray should behave the same on all platforms

How to reproduce it (as minimally and precisely as possible)

• Launch the sample app: TestStrokeDashArray.zip
• Notice the differences between platforms, none are correctly matching Windows
• Pay attention to the distances between the dashes compare to Windows

Related XAML markup:

<StackPanel Orientation="Vertical" Spacing="10" Margin="10">
    <Rectangle Width="100" Height="100"  Stroke="Red"  StrokeThickness="3" />
    <Rectangle  
        IsHitTestVisible="False" 
        Width="100"
        Height="100"
        Stroke="Red"
        StrokeThickness="2" 
        StrokeDashArray="2,2" />
</StackPanel>

Workaround

N/A

Works on UWP/WinUI

Yes

Environment

Uno.UI / Uno.UI.WebAssembly / Uno.UI.Skia

NuGet package version(s)

"Uno.Sdk": "5.2.112"

Affected platforms

WebAssembly, Android, iOS, Mac Catalyst, Skia (WPF), Skia (Linux X11), Skia (macOS), Skia (Linux Framebuffer), Skia (GTK)

IDE

Visual Studio 2022

IDE version

17.9.6

[Youssef1313]

For Skia:

uno/src/Uno.UI.Composition/Composition/CompositionSpriteShape.skia.cs

Lines 59 to 60 in cfb4dfd

	// TODO: Add support for dashes here
	// strokePaint.PathEffect = SKPathEffect.CreateDash();

[agneszitte]

cc @MartinZikmund