How to programmatically check if there will be tofu instead of a character, taking into account font substitution?

Question

Qt

How to check (on WinAPI, Qt or some other library) whether there is support for a particular character in the system? And if so, what font?
OS - Windows. You need it character by character: for example, Windows has several fonts that support Devanagari, one has all the characters in the Vedic Extensions range, except for one, and the other has only a part, and those are clumsy.

Answer 1

One can check for the presence of a character in a font https://stackoverflow.com/questions/34278340/easy-...
A list of fonts can also be obtained from https://stackoverflow.com/questions/2702157/get-li...