RE: Ways to show Unicode contents on Windows?

From: Peter Constable <>
Date: Sat, 13 Jul 2013 07:16:00 +0000

The font fallback mechanisms built into _Windows_ generally aren't designed to be user-configurable. But not everything necessarily relies on these Windows mechanisms. E.g., Office apps have their own mechanisms, and it's not clear to me if or when a Windows fallback mechanism might have effect when using an Office app.

Within Windows, there are multiple mechanisms, created in different eras for different purposes and used in different contexts. A few in the GDI stack can interact; in particular, there's a "font fallback" mechanism in Uniscribe (used in the GDI text stack) that interacts with a "font linking" mechanism in a (mostly) complementary way. Font linking is driven by registry entries, which a brave admin could try tweaking. (Note: these are tailored by the system locale setting, and if you change the system locale setting, any tweaks will get overwritten.)

Some things in Windows use the RichEdit control, which has some of its own font handling logic. It has default font behaviours, but it also exposes APIs that allow a desktop app to control font binding behaviours. (I don't think these are exposed via WinRT APIs in Windows 8, though.)

DirectWrite has fallback data that is not read from the registry or in any way configurable. In Windows 8.1, though, APIs have been introduced that allow an app to specify its own fallback. (It's similar to the WPF APIs for creating a composite font definition.)

I'm not well versed in IE's font handling, though I know that it has a registry entries that get used to specify fonts for fallbacks for different scripts. There's UI that allows the user to configure this to some extent (the Fonts dialog in Internet Options). The mechanisms were not improved for several versions, but I know there are some updates that have been made for IE 11.


-----Original Message-----
From: Christopher Fynn []
Sent: 12 July 2013 09:41 PM
To: Peter Constable
Cc: Unicode List
Subject: Re: Ways to show Unicode contents on Windows?


I'm wondering how do you change the fonts selected by the built-in font fall back in various versions of Windows? I've found that the rendering for certain scripts is less than ideal with some of these fonts. Also the fallback font sometimes overides the font selected by the user in Office and other applications even when the selected font is available.

The only way round this that I've found is to remove the offending fallback font from the system (not always easy)

- Chris

On 11/07/2013, Peter Constable <> wrote:
> For simple scripts that do not require shaping that are not yet
> supported, if you have the font and can select the font in your app,
> then text in those scripts can be displayed. Of course, we don't have
> built-in font fallback for such scripts.
> Peter
Received on Sat Jul 13 2013 - 02:20:28 CDT

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