RFC: full-screen zoom (accessibility via ctrl-scroll)

[ybakos]

Thank you for all things sway. I know there are way more important items, especially for 1.0, but I am submitting a feature request for accessibility.

On MacOS, a "killer" accessibility feature is enabling the user to zoom the entire screen via ctrl + two-finger scroll. While there are utilities for creating "magnifying glass" surfaces that zoom in on small parts of the screen, not many window managers support this like MacOS Quartz Compositor.

It would be amazing, and a big win for folks with accessibility needs, if this were a feature in Sway.

I myself don't have the chops to implement this and submit a PR. 😭

[ddevault]

This is something I'd like to see in sway, too. However,

I myself don't have the chops to implement this and submit a PR. 

This is nonsense, anyone can learn and many people have cut their teeth on sway.

https://drewdevault.com/2017/01/06/Actually-you-CAN-do-it.html

[ybakos]

@SirCmpwn I’m glad you’re a fan of the feature. I also did not mean to sound defeatist, and I do agree about the learning. Perhaps I should have said, “I have too much crap going on to commit to this.” Which isn’t an excuse either. 🤪

[Tormen]

👍 for a screen zoom feature. This is so handy. These days lots of software comes with their own zoom... but still I was using that 1 every day or 2nd-day under KDE and under compiz before that :)

@ddevault : As this feature seems to exist in wayfire, could you have a timeboxed look if there could be any chance to re-use / port this to swaywm or better to wlroots if that's possible ?

[ddevault]

No, it wouldn't be possible to port from wayfire to wlroots.

[ibotty]

Can you give a (very broad) overview on how to tackle this issue for someone not familiar with wayland and wlroots APIs?

[vidister]

@nkreer and I would like to implement this as well. But we're both not familiar with wayland/wlroots and need some hints on how to do start this.

[RazvanRotari]

I had a try to implement this by calling glViewport with a rect bigger that the screen, mostly worked ,but each app is zoomed independently, not the whole screen.

Another way of doing this might be to render the whole screen to a texture and then enlarge that one.

[myisaak]

Read the docs guys (@vidister hope this helps)!
wayland_client: https://wayland.freedesktop.org/docs/html/apb.html
wlroots: https://github.com/swaywm/wlroots/tree/master/protocol

[paolomainardi]

Any updates on this one ?

[frigaut]

Wayfire probably does that through OPENGL, which, unless I am mistaken, sway doesn't use. So I don't think implementation would be trivial. And it's a good thing that sway doesn't use OPENGL - saves your battery.

[emersion]

Sway does use OpenGL (it can also use Pixman on devices without a GPU).

[paolomainardi]

@emersion how much do you think is complex to build this feature on the current Sway codebase ? Assuming that all the needed pieces are still in place.

[paolomainardi]

It does!’t look like rocket science so far: https://github.com/WayfireWM/wayfire/blob/224bb669836ce987a7e17fe53291bb87a7b0140d/plugins/single_plugins/zoom.cpp

[frigaut]

Sway does use OpenGL (it can also use Pixman on devices without a GPU).

my bad

[Beryesa]

What about vulkan renderer

[teknico]

I had a try to implement this by calling glViewport with a rect bigger that the screen, mostly worked ,but each app is zoomed independently, not the whole screen.

Actually, zooming just one window is what I need. Is there a window manager that has this feature?

[tyalie]

I would also very much wish to see this feature come to sway. It would be awesome in order to explain to other people what you're doing right now.

[Simbi0z]

Is there a tool for wlroots based compositors that implements the magnifying glass feature?

[mooreye]

If anyone's interested, I hacked together a simple zoom in/out tool bound to a key. It zooms all outputs by a scale factor of ±0.1 either in or out. If scale is >=5, it will refuse to zoom in, and if it is <=0.25, it will refuse to zoom out, because overdoing it made my output glitchy and started killing windows. Change $mod+5 to your own key, and put this in ~/.config/sway/config:

# zoom in/out
bindsym --inhibited $mod+5       output * scale 1
bindsym --inhibited $mod+Shift+5 exec set -euo pipefail && scale=$(bc -l <<< $(swaymsg -t get_outputs | jq -r '.. | select(.focused?) | .scale')+.1) && [[ $(bc -l <<< "${scale} < 5"  ) == 1 ]] && swaymsg "output * scale ${scale}"
bindsym --inhibited $mod+Ctrl+5  exec set -euo pipefail && scale=$(bc -l <<< $(swaymsg -t get_outputs | jq -r '.. | select(.focused?) | .scale')-.1) && [[ $(bc -l <<< "${scale} > .25") == 1 ]] && swaymsg "output * scale ${scale}"

[vishalpaudel]

👀

any updates? the above command from @mooreye doesn't seem to work for me, pipefail doesn't seem like an option for me.

[mooreye]

👀

any updates? the above command from @mooreye doesn't seem to work for me, pipefail doesn't seem like an option for me.

I guess your sh command corresponds to a different shell than bash where there is no set -o pipefail option? In any case, try pasting these exec ... commands into a file with #!/bin/bash as the first line, make it executable, and put path to this file as a command.

[sertonix]

You can also remove o pipefail since it isn't used.

[bobblkabb]

bindte = CTRL SHIFT, mouse_down, exec, hyprctl keyword cursor:zoom_factor "$(hyprctl getoption cursor:zoom_factor | grep float | awk '{print $2 + 0.05}')"
bindte = CTRL SHIFT, mouse_up, exec, hyprctl keyword cursor:zoom_factor "$(hyprctl getoption cursor:zoom_factor | grep float | awk '{print $2 - 0.05}')"

[vishalpaudel]

ya, the command works using bash, but doesn't really do what I needed, a workaround I have is to

1. use grimshot save screen
2. open the saved image in fullscreen in firefox
3. zoom using the firefox image viewer

I could maybe do something like:

zoomfile=/tmp/zoomimage.png grimshot save screen $zoomfile | xargs firefox --new-tab

[telychko]

All of that approaches is a workaround. It should be implemented in compositor (of course if it's not against it's philosophy).

That's my workarounds:

SCALE="$(swaymsg -t get_outputs | jq ".[] | select(.focused == true) | .scale" | awk -vv="$1" '{print($1+v)}')"
swaymsg "output - scale $SCALE"

Where $1 above is the scale factor