resize-window doesn't apply given increment accurately

[xeyownt]

Describe the bug I'm using remote-control and resize-window to build a tab layout with window of given size (using layout splits). When applying the resize-window the new window sizes are not the one expected.

To Reproduce Steps to reproduce the behavior:

1. Run the following script in a kitty --config NONE -o allow_remote_control=yes window:

   
   #! /bin/bash

function do-resize() { INCREMENT=$1 L1=$(kitty @ ls | jq '.[].tabs[].windows[] | select( .title == "left" ) | .columns') R1=$(kitty @ ls | jq '.[].tabs[].windows[] | select( .title == "right" ) | .columns') kitty @ resize-window --match title:left --increment $INCREMENT --axis horizontal L2=$(kitty @ ls | jq '.[].tabs[].windows[] | select( .title == "left" ) | .columns') R2=$(kitty @ ls | jq '.[].tabs[].windows[] | select( .title == "right" ) | .columns') echo "Left: $L1 -> $L2 [$((L2 - L1))] Right: $R1 -> $R2 [$((R2 - R1))]" } kitty @ launch --type tab --title "left" --tab-title "first" > /dev/null kitty @ goto-layout --match title:first splits kitty @ launch --match title:first --location vsplit --title "right" --keep-focus > /dev/null do-resize 2 do-resize 2 do-resize 2 do-resize 2 do-resize 2

2. This gives the output below. We see that we sometimes get a wrong increment, and sometimes the increment on the left and right window is different.

Left: 106 -> 108 [2] Right: 106 -> 104 [-2] Left: 108 -> 110 [2] Right: 104 -> 102 [-2] Left: 110 -> 113 [3] Right: 102 -> 100 [-2] Left: 113 -> 115 [2] Right: 100 -> 97 [-3] Left: 115 -> 117 [2] Right: 97 -> 95 [-2]

3. Using an increment of `10`, we get the following output, where the increment is always wrong. In fact the bigger the increment the bigger the difference.

Left: 106 -> 117 [11] Right: 106 -> 95 [-11] Left: 117 -> 128 [11] Right: 95 -> 84 [-11] Left: 128 -> 139 [11] Right: 84 -> 73 [-11] Left: 139 -> 151 [12] Right: 73 -> 62 [-11] Left: 151 -> 162 [11] Right: 62 -> 51 [-11]

4. The same applies for `hsplit` and `--axis vertical`.

**Environment details**

kitty 0.29.1 (a0341af3f8) created by Kovid Goyal Linux zavcxl0007 6.1.0-6-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.15-1 (2023-03-05) x86_64 Debian GNU/Linux bookworm/sid zavcxl0007 /dev/tty

Running under: X11 Frozen: True Paths: kitty: /home/peetersm/.local/kitty.app/bin/kitty base dir: /home/peetersm/.local/kitty.app/lib/kitty extensions dir: /home/peetersm/.local/kitty.app/lib/kitty-extensions system shell: /bin/bash Loaded config overrides: allow_remote_control yes

Config options different from defaults: allow_remote_control yes

Important environment variables seen by the kitty process: PATH /home/peetersm/bin/local:/home/peetersm/bin:/home/peetersm/.local/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/peetersm/.fzf/bin LANG en_US.UTF-8 EDITOR vim SHELL /bin/bash DISPLAY :0 USER peetersm XDG_MENU_PREFIX gnome- LC_MONETARY en_DK.UTF-8 XDG_SESSION_DESKTOP gnome-xorg XDG_SESSION_TYPE x11 LC_PAPER en_DK.UTF-8 XDG_CURRENT_DESKTOP GNOME XDG_SESSION_CLASS user LC_MEASUREMENT en_DK.UTF-8 XDG_RUNTIME_DIR /run/user/1000 LC_TIME en_DK.UTF-8 XDG_DATA_DIRS /usr/share/gnome:/usr/local/share/:/usr/share/ LC_NUMERIC en_DK.UTF-8

[kovidgoyal]

windows sizes in kitty are based on biases not cell sizes so when you resize in cells you will get a bias that comes close to the asked for size but there is no guarantee it will be exact. That said I am sure the bias calculations could be improved for better consistency, patches are welcome, relevant code is in the layout folder.

[iacore]

@kovidgoyal this command changes the window size on vertical split: kitty @ resize-window --increment=0

[kovidgoyal]

That's completely unrelated: https://github.com/kovidgoyal/kitty/commit/15dd95d420148720efce8dee9731a192903c03fb