Conhost replication - Consolas font-size off by one pixel?

[jojje]

I've been considering windows terminal for years, but the inability of it to provide sharp text like cmd.exe was a non-starter. In the latest version (1.23.250314002-preview) it seems the terminal is now very close, but still not there.

The row height (line height) is now aligned with conhost when using Consolas, with font size 10 in Windows Terminal and font size 16 in conhost, but the rendered glyphs seem to be one pixel smaller than in conhost. This makes the text smaller than conhost, less sharp and thus harder to read.

The conhost font seems to make an optimal trade-off between readable text and wasted screen real-estate, and it would be great if this same ergonomic could be obtained in Windows Terminal as well.

Question: Is there anything in the settings.json that can be set to address this issue?

---

System details:

• Windows Terminal version: 1.23.250314002-preview (from github releases page)
• Windows version: 10.0.19045.5247
• Graphics card: RTX 4090 with nVidia driver version 566.14

Below are two screenshots comparing Windows Terminal and conhost cmd.exe side by side, to make this rendering issue clear. The second screenshot is a zoomed in view from photoshop with the 1-pixel glyph size difference framed.

settings.json file used.

{
    "$help": "https://aka.ms/terminal-documentation",
    "$schema": "https://aka.ms/terminal-profiles-schema-preview",
    "actions": [],
    "copyFormatting": "none",
    "copyOnSelect": false,
    "defaultProfile": "{0caa0dad-35be-5f56-a8ff-afceeeaa6101}",
    "keybindings": 
    [
        {
            "id": "Terminal.CopyToClipboard",
            "keys": "ctrl+c"
        },
        {
            "id": "Terminal.PasteFromClipboard",
            "keys": "ctrl+v"
        },
        {
            "id": "Terminal.DuplicatePaneAuto",
            "keys": "alt+shift+d"
        }
    ],
    "newTabMenu": 
    [
        {
            "type": "remainingProfiles"
        }
    ],
    "profiles": 
    {
        "defaults": { "antialiasingMode": "cleartype" },
        "list": 
        [
            {
                "commandline": "%SystemRoot%\\System32\\cmd.exe",
                "font": 
                {
                    "face": "Consolas",
                    "size": 10
                },
                "guid": "{0caa0dad-35be-5f56-a8ff-afceeeaa6101}",
                "hidden": false,
                "name": "Command Prompt"
            }
        ]
    },
    "schemes": [],
    "themes": []
}

[DHowett]

Thanks for asking! This is a topic near and dear to Leonard!

It's currently Sunday, so I'm not able to write up a more comprehensive reply... but I did want to point out one thing:

The colored pixels you are seeing on every stroke of every glyph is ClearType.

Grayscale antialiasing would not use colors, but rather shades of gray. Aliased rendering would not use either. :)

[lhecker]

I wrote about this topic in this issue here: #14165 (comment)
Edit: It seems you already found that comment before.

tl;dr: First, enable ClearType in the advanced settings of the default profile. Then, to convert Consolas font sizes in conhost into font sizes in Windows Terminal, divide the size by 1.561197917. For instance, the default conhost size 16 is 10.248540448 in Windows Terminal. This should then match almost perfectly.

[jojje]

Thanks a million Leonard (@lhecker) !
Worked perfectly. I can now finally start using windows terminal :)

PS, about cleartype, I assume you commented on my initial post which I then edited after having verified the effect of the cleartype setting, so that only the question about the font size remained. But I think this example above is good for others who notice cleartype isn't enabled by default, and must be explicitly set in the settings.