A missing layout option: split-empty-space-evenly ?

[magthe]

I tried out niri a few months ago, but didn't make the switch. Now I've come back and found the option always-center-single-columns. I'm using it together with center-focus-column "never" and liking it... though I've realised I don't love it. I think the current behaviour favours leaving windows where they are, and I can appreciate that's something some people like, but personally I'd like a behaviour that favours distributing empty space evenly on both edges of the screen (which will make all columns visible when possible). I'll try to illustrate what I mean.

Setup

I have a config where I cycle between column widths of 1/3, 1/2, and 2/3s of my screen. My layout contains

layout {
    center-focused-column "never"
    always-center-single-column
    ...
}

Scenario α

1. open 1st window
2. open 2nd window

Current behaviour

---------------------------------------------
|              | window0      |             |
|              |              |             |
|   empty      |              |   empty     |
|              |              |             |
|   1/3        |    1/3       |   1/3       |
|              |              |             |
---------------------------------------------

---------------------------------------------
|              | window0      | window1     |
|              |              |             |
|   empty      |              |             |
|              |              |             |
|   1/3        |    1/3       |     1/3     |
|              |              |             |
---------------------------------------------

All the empty space is on the left.

Suggested behaviour

---------------------------------------------
|              | window0      |             |
|              |              |             |
|   empty      |              |   empty     |
|              |              |             |
|   1/3        |    1/3       |   1/3       |
|              |              |             |
---------------------------------------------

---------------------------------------------
|  e   | window0      | window1      |  e   |
|  m   |              |              |  m   |
|  p   |    1/3       |    1/3       |  p   |
|  t   |              |              |  t   |
|  y   |              |              |  y   |
| 1/6  |              |              | 1/6  |
---------------------------------------------

There's equal amounts of empty space outside the columns.

Scenario β

1. open 1st window
2. open 2nd window
3. open 3rd window
4. resize 3rd window to 2/3 size
5. close 3rd window

Current behaviour

---------------------------------------------
|              | window0      |             |
|              |              |             |
|   empty      |              |   empty     |
|              |              |             |
|   1/3        |    1/3       |   1/3       |
|              |              |             |
---------------------------------------------

---------------------------------------------
|              | window0      | window1     |
|              |              |             |
|   empty      |              |             |
|              |              |             |
|   1/3        |    1/3       |     1/3     |
|              |              |             |
---------------------------------------------

All the empty space is on the left.

---------------------------------------------
| window0      | window1      | window2     |
|              |              |             |
|              |              |             |
|              |              |             |
|   1/3        |    1/3       |     1/3     |
|              |              |             |
---------------------------------------------

---------------------------------------------
| window1      | window2                    |
|              |                            |
|              |                            |
|              |                            |
|   1/3        |    2/3                     |
|              |                            |
---------------------------------------------

---------------------------------------------
| window1      |                            |
|              |                            |
|              |    empty                   |
|              |                            |
|   1/3        |    2/3                     |
|              |                            |
---------------------------------------------

The column with window0 is outside the screen, and all the empty space is on the right.

Suggested behaviour

---------------------------------------------
|              | window0      |             |
|              |              |             |
|   empty      |              |   empty     |
|              |              |             |
|   1/3        |    1/3       |   1/3       |
|              |              |             |
---------------------------------------------

---------------------------------------------
|  e   | window0      | window1      |  e   |
|  m   |              |              |  m   |
|  p   |    1/3       |    1/3       |  p   |
|  t   |              |              |  t   |
|  y   |              |              |  y   |
| 1/6  |              |              | 1/6  |
---------------------------------------------

There's equal amounts of empty space outside the columns.

---------------------------------------------
| window0      | window1      | window2     |
|              |              |             |
|              |              |             |
|              |              |             |
|   1/3        |    1/3       |     1/3     |
|              |              |             |
---------------------------------------------

---------------------------------------------
| window1      | window2                    |
|              |                            |
|              |                            |
|              |                            |
|   1/3        |    2/3                     |
|              |                            |
---------------------------------------------

---------------------------------------------
|  e   | window0      | window1      |  e   |
|  m   |              |              |  m   |
|  p   |    1/3       |    1/3       |  p   |
|  t   |              |              |  t   |
|  y   |              |              |  y   |
| 1/6  |              |              | 1/6  |
---------------------------------------------

There's equal amounts of empty space outside the columns, and both columns are visible.

Consequences

• Centring the focused column doesn't always have any effect as there has to be enough non-empty space on both sides.

[YaLTeR]

Yeah, this makes sense. PaperWM works this way, too.

One of the problems however is how to do interactive resize nicely. Currently in always-centered mode, it will resize twice as fast and remain centered. In this case however I'm afraid we may have to make do with stationary resizing followed by windows moving into place.

[magthe]

I think that's more than fair...TBH I have a suspicion it'd be slightly confusing if the window I'm interactively resizing is moving around at the same time.

Anyway, I'm happy to hear you think it makes sense... I'm eager to try it out when it lands in a release 🙏