The problem with `window-configuration-change-hook` is that it isn't called
all the times we would need it. For example, it's not called when you do
`other-window` via `C-x o`.

-Steven


On Wed, Apr 3, 2013 at 3:13 PM, Stefan Monnier <monnier@iro.umontreal.ca>wrote:

> > We could add overlays to every buffer, and whenever you change windows,
> > remove the overlay from the current buffer and add it back to the
> previous
> > buffer.
>
> Auto-adding the overlays can be done in window-configuration-change-hook.
> We're talking about N overlays per buffer where N is small (it's number of
> windows where the buffer is displayed), so there's no performance
> problem there.
>
> > Or, we could have it reversed. We could only have an overlay on the
> current
> > buffer at any given time, and give it the window of (selected-window),
> and
> > keep updating these any time you change buffers or windows.
>
> That would be a lot simpler, indeed, but I think it will be difficult
> to make it look good.
>
>
>         Stefan
>
>
>