Re: New library wallpaper.el pushed to master

[Stefan Kangas]

Po Lu <luangruo@yahoo.com> writes:

> Po Lu <luangruo@yahoo.com> writes:
>
>> Why does it check `display-graphic-p'?
>> Setting the background image should work in a TTY as well.

If I'm not mistaken, under X, you would need $DISPLAY to be set for it
to work.  And that variable is not set by default in a TTY.

Testing this on the Linux console, it only works if I do:

    DISPLAY=:0.0 feh --bg-fill some-image.png

My assumption is that $WAYLAND_DISPLAY works similarly (but I've never
used Wayland so I have no idea really).

Do you have any ideas for how to do this better?  I guess that

    (setenv "DISPLAY" ":0.0")

will only work for single-user machines.  Maybe that's okay, though.

Or maybe we should just check if $DISPLAY and/or $WAYLAND_DISPLAY are
set first?

Or maybe we should just ignore any errors and let users figure it out?
But that seems a bit drastic, perhaps.

> BTW, what about actions usually taken to modify the wallpaper such as
> scaling, cropping, and offsets?  Shouldn't wallpaper-set take several
> arguments to specify those?

For now, the idea is that the user will be able to configure this by
changing `wallpaper-commands'.  Ideally, we would have a defcustom to
control the default operation while being agnostic of the actual command
used.  But then you have different capabilities in different software to
consider too.