Terminal: Incorrect rendering for Gorched terminal-based game.

[oising]

Another render canary for you, @miniksa: Gorched (scorched earth game, terminal version.) It even has a Windows installer, so I'm guessing it was tested on alacritty or something.

From: https://github.com/zladovan/gorched

It should look like:

But actually looks like (with default options):

When I run with "safe" options, gorched --low-color --ascii-only I see:

No matter what width I set, I couldn't get it to align. Additionally, it seems there's some persistent glitching after the game is quit (ctrl+c) with margins and wrapping.

[oising]

I had a look at the underlying go library that the game is built on, termloop. It seems none of the examples there render correctly either, but they are significantly simpler. Maybe that would be easier to debug. I set up the environment like so:

scoop install go
go get -u github.com/JoelOtter/termloop
git clone https://github.com/JoelOtter/termloop

Then I ran some of the examples in: /tree/master/_examples -- they all render messed up, or don't work at all. I wonder what it's doing that's so wacky.

[DHowett]

Termbox, the library Termloop builds on, notoriously (at least, they're notorious to me :smile:) tries to be clever about interacting with the Windows console instead of using our VT support. I wonder what _they're_ doing.

This is probably something "conhost recording" would help with. . . :smile:

Thanks for looking at this, @oising!

[j4james]

This is essentially a duplicate of #4363. The game uses console API calls to write to the screen buffer, and it looks like a lot of the blank areas of the background are actually the zero codepoint. Ideally conpty should be translating those to something like a space or non-breaking space, but it's just passing them through as a null control, which then ends up getting ignored.

[oising]

Oh, lordy. I didn't look _that_ closely. I just presumed it was VT all the way ... look what I've become! Close as a dup if you see fit, guys.

[j4james]

I should mention the colors also don't work (i.e. some elements will be invisible) unless you've used the --low-color option, because obviously the console APIs can only handle 16 colors.

That said, you can actually run the Linux build in WSL, and that works perfectly (as far as I can tell), because it's then using actual VT sequences.