Add ability to get current window opacity

[acheronfail]

Description: sway can currently set opacity very easily in different ways, e.g., swaymsg opacity 0.5 or for_window [<criteria>] opacity 0.75. But there's no way to get the opacity of a window.

I would like to ability to bind a key to 'cycle through opacity values', but I cannot implement this without being able to query the current opacity value for a given window.

Enhancement Request: in swaymsg -t get_tree's output, an opacity field should be returned with the window's current opacity value.

(I couldn't find a non-sway way to get opacity either, through other Wayland tools, etc. If such a way exists it could be a workaround, so please let me know. :slightly_smiling_face:)

[bl4ckb0ne]

I don't get the use case, you can just keep the current opacity locally when cycling through it.

(I couldn't find a non-sway way to get opacity either, through other Wayland tools, etc. If such a way exists it could be a workaround, so please let me know. slightly_smiling_face)

The opacity is a sway feature, Wayland has nothing to do with it.

[rpigott]

Related: https://github.com/swaywm/sway/issues/6574#issuecomment-933070655

[acheronfail]

I don't get the use case, you can just keep the current opacity locally when cycling through it.

Maybe I'm missing something? As far as I can tell, it's not possible to have a binding that cycles through opacities...

As an example, on i3 (with picom) I have something similar to this:

bindsym $mod+t exec 'picom-trans --toggle 0.5'

Which, when used will toggle the transparency of the focused window. With a script it's easy with picom-trans to get the transparency, and then use that to figure out what the next opacity should be if cycling through many. (This is what I have in i3, cycling though 1.0, 0.5, 0.75 opacity values).

What do you mean "keep the current opacity locally"? :thinking:

[rickyrsyah]

I don't get the use case, you can just keep the current opacity locally when cycling through it.

Maybe I'm missing something? As far as I can tell, it's not possible to have a binding that cycles through opacities...

As an example, on i3 (with picom) I have something similar to this:

bindsym $mod+t exec 'picom-trans --toggle 0.5'

Which, when used will toggle the transparency of the focused window. With a script it's easy with picom-trans to get the transparency, and then use that to figure out what the next opacity should be if cycling through many. (This is what I have in i3, cycling though 1.0, 0.5, 0.75 opacity values).

What do you mean "keep the current opacity locally"? thinking

check this for your case https://gist.github.com/rickyrsyah/05e28ab2adbb5472f9269acaa072738d

[vdegenne]

@acheronfail I don't know if you figured this out but here a script that will toggle the opacity of the current window:

#!/usr/bin/bash

swaymsg opacity plus 0.01

if [ $? -eq 0 ]; then
        # opacity was not 1, we toggle off
        swaymsg opacity 1
else
        # opacity was 1, we toggle on
        swaymsg opacity 0.5
fi

Just need one keybind in sway config

bindsym $mod+o exec toggle-transparency.sh