[SilverCode]

"combine (two or more images) to make a single picture, especially electronically" ... sucks?

I can't even begin to think how you would present multiple windows to a user if you didn't composite them into a single image. Even if you are doing a 3D virtual desktop, you still have to composite the layers down to 2 single slightly offset images.

[account42]

Compositing in the context of window management hase a more specific meaning:

https://en.wikipedia.org/wiki/Compositing_window_manager

vs.

https://en.wikipedia.org/wiki/Stacking_window_manager

There are advantages and disadvantages to both approaches. Note that X.org is traditionally a stacking window manager but has had the compositing model bolted on for a long time now.

[yencabulator]

Compositing WM is not "versus" stacking WM. Practically all mainstream Wayland desktops are floating ("stacking") based UI paradigms, while using compositing to construct the final screen image. The wikipedia article you linked to shows examples of stacking window management on the compositing window manager page!

Are you thinking of tiling WMs? The major tiling Wayland compositors support floating windows when you want them, too.

[account42]

No, from the Wiki article on stacking WMs (empahsis mine):

> A stacking window manager (also called floating window manager) is a window manager that draws and allows windows to overlap, without using a compositing algorithm. All window managers that allow the overlapping of windows but are not compositing window managers are considered stacking window managers, although it is possible that not all use exactly the same methods.

It's possible that you have another definition but for me (and it seems for Wikipedia) the distinction is that a stacking WM does not keep buffers for individual windows but instead has them draw directly into the desktop buffer (details vary, the programs themselves might not have access to the buffer but send pixmaps that get blitted there). This results in lower resource usage and fewer copies but requires programs to redraw newly exposed regions when you move a window which may result in visible artifacts when programs cannot render fast enough.