fix(tiling): Windows launching onto window that isn't focused

[mmstick]

Closes #1166

[jacobgkau]

The wording in #1137 seems to imply that windows should quarter-tile first. After this change, I am now seeing the "incorrect" behavior of new windows continuing down the same side of a fork instead of alternating back to quarter tile:

simplescreenrecorder-2021-09-10_09.30.41.mp4

This behavior does seem logical, but we need clarification on what the expected behavior is.

[mmstick]

Windows should always launch onto the window that is focused, so you can expect to know where the window is tiled.

[jacobgkau]

I understand, #1137 is just referring to the split happening horizontally instead of vertically.

[jackpot51]

@jacobgkau this behavior in this PR is the correct behavior as far as I know. A new window should always halve the focused window, or join the focused window's stack.

[jacobgkau]

I'm seeing cases across multiple displays where a new window is not joining a focused window:

Screencast.from.09-10-2021.10.15.20.AM.mp4

I believe the key to recreating this is switching between several stacked windows just before switching focus to another display and opening a new one.

[jacobgkau]

The stacking case from before is fixed. However, I'm still seeing new windows appear on the non-focused display if the mouse cursor is on the non-focused display. (Basically, the cursor seems to override focus for choosing which display to use.)

simplescreenrecorder-2021-09-14_08.50.12.mp4

Is this how it's supposed to work? It seems incorrect based on the description of "should always launch onto the window that is focused."

[mmstick]

It should be the active window that matters more than the mouse position. Will look

[jacobgkau]

That commit fixed the remaining issue with window opening in tiled mode. Windows now always open on the focused window/stack, regardless of cursor position.

However, it introduced a change of behavior when entering tiling mode; all windows now tile onto the primary display. Before:

simplescreenrecorder-2021-09-14_10.19.41.mp4

After:

simplescreenrecorder-2021-09-14_10.20.12.mp4

Can existing windows be tiled onto their current display when entering tiling mode, without changing the behavior for opening new windows?

[mmstick]

Sure. Done.

[jacobgkau]

Everything looks good now. Regression testing passed:
shell-pr1171-hirsute.txt
shell-pr1171-focal.txt