Neovide: Text is not rendered vertically centered on each line, but is rendered too high up

[Hubro]

Describe the bug

Text is not rendered at the vertical center of each line, but is instead rendered near the top:

Here's how it looks in xfce4-terminal:

Font used in both pictures: Liberation Mono (size 10 in terminal, h14 in Neovide)

Desktop (please complete the following information):

• OS: Arch Linux
• Neovide Version: main branch (b0222d206e6c0775d0f75a470bdca355251e7713)
• Neovim Version master branch (v0.5.0-dev+1459-g384f9870f)

Please run neovide --log and paste the contents of the .log file here:

https://gist.githubusercontent.com/Hubro/d53c69b04bb71035accc021790ffe1db/raw/066de6b886f69fa1bac5642660787bee5bfcb8f8/neovide_rCURRENT.log

[Kethku]

This is a known issue. I haven't quite figured out what combination of metrics gets the desired effect from swash.

[Kethku]

https://github.com/Kethku/neovide/pull/795 Could folks try this branch? It seems to act closer to what I expect, but I'm not sure if its the right fix.

[clason]

Yes, that is much better but not perfect yet:

(Look at the parentheses)

[Kethku]

Can you grab a comparison screen cap? It's hard to tell what the difference is

[clason]

Yeah, the difference is smaller than I made it out to be ;) But at least the top of the parentheses no longer touch the border of the cell. Here's the same on main:

[Kethku]

Ah sorry I meant a comparison to a terminal ground truth

[Hubro]

@Kethku

Terminal ground truth (Alacritty, Liberation Mono 10pt):

Neovide gd2e33b8 (Liberation Mono h14):

Seems to consistently draw everything 1px too high up on the line.

Neovide vertical-positioning-fix (Liberation Mono h14):

Neovide now draws the text positioned more or less identically to Alacritty! I tested this and got the same results with Roboto Mono and Source Code Pro as well. It definitely seems to me like this patch fixes the vertical positioning issue.

[Kethku]

This is merged, so I think this is fixed.