Layer shell effects damage tracking on default background

[WillPower3309]

#295 fixed a bug where the default gray background has damage tracking issues with blur / shadow enabled:
https://github.com/WillPower3309/swayfx/assets/13266308/45895e80-22ff-47d1-8cd9-f9e9facf7f17

It seems like this issue is still present with layer shell surfaces

[ErikReider]

Is this still an issue btw? Can't seem to reproduce...

[ldelossa]

@ErikReider I'm not 100% sure but I think I'm experiencing this on Gtk4 layer shell surfaces.

2024-05-16T07.47.40-04.00.mp4

Here is an example from Way-Shell's OSD.

Its an animated window which animates to 0 margin (bottom of the screen) and then the window is hid. However, the shadow artifacts remain present, until the area is damaged and the frame is re-rendered. I'm not sure if this is exactly the same issue, but looks close (maybe its this issue see in practice?). If its not, just lmk and I'll delete this message.

[ldelossa]

one thing I noticed also is, this only happens when wallpapers are used or the layer-shell window is present ontop of another client window. If I put a plane white or black color background, no artifact is left.