[Interest] Round Corners of ShellSurfaceItem

[Mario Kastner]

Hello Friends!

I am trying to create a Wayland based desktop environment with a
slightly different approach. My window decorator is not on top of a
window but aside of it:


round ->  /---|---------------------\  <-- round
          | x |                     |
          | _ |                     |
          |   |  ShellSurfaceItem   |
          |   |                     |
          |   |                     |
          |   |                     |
round ->  \---|---------------------/ <-- round

I've managed to draw the decorator through a canvas element. Works
fine. But somehow, I am not able to round the right side corners of the
ShellSurfaceItem. I've also tried to put the whole window under a
OpacityMask (rounded rectangle) which worked quiet well, but
unfortunatly every right-click menu was cutted away when it leaves the
area.

I haven no idea where to start. Maybe one of you could give me a hint,
or some examples.

Sincerely
Mario Kastner