skia path offsetting

[Martin]

Hi,

I want to draw a path with dashed, rounded outline - like in the screenshot.

Is there path-offsetting functionality built into skia, is this functionality planned?

This is image created in photoshop.

I've read around the web an found this is a tough problem to solve. But you're google so I dare to ask here once.

[paul....@gmail.com]

It is possible to do this in Skia.

The technique is as follows:

Assuming B is the blue path, and R is the red path.

1. Make a paint with stroke width set to R's stroke width.

2. Use SkPaint getFillPath() method on B to get a path (S) equivalent to a stroked B

3. Use Path Ops to create R: a union of B and S.

R should contain the desired red path.

I can't guarantee that it will work well for every possible path.  But here's a fiddle demonstrating the technique in action.

https://fiddle.skia.org/c/7948297ded37c8f591dbd342256ed099

Hope this helps.

Paul