sixels printed inside terminal emulator does not get cleared

[shadow-absorber]

1. Graphical issue inside a terminal pane (eg. something does not look as it should)

1. Delete the contents of /tmp/zellij-1000/zellij-log, ie with cd /tmp/zellij-1000/ and rm -fr zellij-log/ (/tmp/ is $TMPDIR/ on OSX)
2. Run zellij --debug
3. Run stty size, copy the result and attach it in the bug report
4. Recreate your issue.
5. Quit Zellij immediately with ctrl-q (your bug should ideally still be visible on screen)

Please attach the files that were created in /tmp/zellij-1000/zellij-log/ to the extent you are comfortable with.

Basic information

zellij --version: zellij 0.39.2

stty size: 52 208

uname -av or ver(Windows): Linux sam-computer 6.7.6-arch1-1 #1 SMP PREEMPT_DYNAMIC Fri, 23 Feb 2024 16:31:48 +0000 x86_64 GNU/Linux

Further information

Reproduction steps, noticeable behavior, related issues, etc

after running img2sixel /path/to/png.png and then running the clear command the image does not get cleared from the screen
this is in the alacritty graphics branch that is working flawlessly outside of zellij

zellij.log

[shadow-absorber]

just tested with xterm too and same issue with sixels not getting cleared when running clear command

[manueldeprada]

As @Zettexe pointed out in #3372 , this is probably a consequence of sixel images being rendered with twice the height they should. Example:

link to the test image

[lypanov]

As @Zettexe pointed out in #3372 , this is probably a consequence of sixel images being rendered with twice the height they should. Example:

link to the test image

Nice test case. I'll look into this issue next as it's breaking my sixel based workflow.

[manueldeprada]

Weirdly enough, I recently switched to a branch of Alacritty with sixel support and there zellij's sixel are correct...

next week I got some time, I will investigate

[lypanov]

This may be the key - foot supports aspect ratios and defaults to 2:1. I'll look into this part of the zellij code this coming week.

…

On Sat, Jul 20, 2024, at 21:12, Manuel de Prada Corral wrote: Weirdly enough, I recently switched to a branch of Alacritty with sixel support <alacritty/alacritty#4763> and there zellij's sixel are correct... image.png (view on web) <https://github.com/user-attachments/assets/3aa357f8-9ae5-459d-97b1-c38c5cdbd7a4> next week I got some time, I will investigate — Reply to this email directly, view it on GitHub <#3173 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAACN4JNHXVQUH6IXLVJ7DZNKZDVAVCNFSM6AAAAABEAWJTWKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDENBRGI3DKNBWHE>. You are receiving this because you commented.Message ID: ***@***.***>

[lypanov]

Yeah that's it, I was able to use wezterm record to show that zellij is not passing through the raster attributes needed to fix the default 2:1 ratio (spec default) that foot uses and other terminal emulators fail to correctly default to. Comment from Aram on the line in question: // we ignore pan/pad because (reportedly) no-one uses them. Alas some emulators are trying to get to spec on this. I'll look into writing a patch to pass this through from the tokenizer.

[lypanov]

Okay verified the theory by hacking sixel-image to always spew a hardcoded override to 1:1 ratio. Foot now renders your test case correctly. Next up will be to understand enough of the spec to add pan/pad roundtripping and understand how that fits into Aram's concerns.