GUI applications (evince) stuck in top-left corner and not scaling to --virtual-monitor-size

[YqI777]

Environment:

OS: Linux (Remote Cluster / Login Node)

Terminal: Windows Terminal (supporting Sixel)

Version: term.everything v0.7.6

The Issue: I am trying to view a PDF file using evince inside term.everything. Despite setting a large --virtual-monitor-size (e.g., 1600x1000 or 7000x4500), the application window remains fixed at its default minimum size in the top-left corner of the terminal canvas.

What I've tried:

Used --virtual-monitor-size with various resolutions.

Used --support-old-apps to trigger the window manager, but the app still doesn't maximize to fill the canvas.

Tried evince --fullscreen, but it only fills the small sub-window in the corner, not the entire terminal display area.

Verified TERM_EVERYTHING_PIXEL_MODE=SIXELS is working as images are visible, just incorrectly scaled/positioned.

Expected Behavior: The GUI application should automatically maximize or fill the entire area defined by --virtual-monitor-size, especially when using --support-old-apps.

Screenshots:

[j4james]

I suspect term.everything is relying on a TIOCGWINSZ syscall to determine the screen size, and Windows doesn't have anything like that. So when you connect to a Linux box with ssh, the ssh client tries to pass along some values that the server can initialize TIOCSWINSZ with, but this will usually only include ws_row and ws_col (it won't know the pixel dimensions, and they aren't technically standard anyway). If you're using win32-openssh it's even worse, because that's been known to fill in completely fake pixel values (something like 640x480 if I remember correctly).

So if an app needs to reliably determine the pixel dimensions of a terminal, it should really be using one or more of the XTWINOPS escape sequences:

• CSI 14 t reports the window size in pixels
• CSI 16 t reports the cell size in pixels

Assuming you already know the number of rows and columns in the terminal, you can easily determine the window size from the cell size, or vice versa, with a simple multiplication or division, so you only need one of those.

However, it's worth noting that the window size is not a very well defined concept (this actually applies to the pixels dimensions returned by TIOCGWINSZ too). Some terminals will return the size of the full terminal window (potentially including things like the scrollbar, menu bar, and window borders). Others will report just the text area of the terminal.

So CSI 16 t is the most accurate, but CSI 14 t is a little more widely supported, so it's best to try 16 first with a fallback to 14.

[mmulet]

Thanks for the issue, and thanks to @j4james for the fix. I'll implement it in the next update, which I'm hoping to get done this week/weekend.