Is it possible with I3Wm to populate an entire workspace with determined size, position and commands for each window?
I know I can do i3-msg "exec xterm -e 'ls; bash'" to create a new window, but I can't specify his position and size.
Maybe there is also an alternative by declaring via JSON the layout or something like that?
Since version 4.8, something like that is part of i3 and there's a detailed guide on the website, but here's a short version:
Once you've set up a workspace like you want it to be, save its layout with
i3-save-tree --workspace <whichever workspace you want> > ~/.i3/layout-ws-<xyz>.json
into the file ~/.i3/layout-ws-xyz.json. You'll then need to edit that file to enable criteria that match windows in the layout.
After that, you can restore that layout with
i3-msg "workspace <your workspace>; append_layout ~/.i3/layout-ws--<xyz>.json"
This will open placeholder windows on that workspace and when a window matching the criteria enabled in the layout file appears, it will be placed in the corresponding placeholder window.
class="^Google-chrome$", you still need to start an application whose window has that specific class; the application will not be started automatically.
i3-msg "workspace 1; append_layout /path/my/layout.json; [class='xterm'] exec xterm and worked like a charm. This JSON declaration is definitely an awesome feature, thank you!
-geometry=WxH+X+Yswitch toxterm. The W and H are in characters, the X and Y are in pixels. Note you could also use the snazzier terminal from (e.g.) XFCE stand-alone if you want, which uses the same stylegeometryspec. The GNOME terminal may be portable too; KDE'skonsoledefinitely is but does not allow you to dictate the geometry.