On iOS, can I access the system-provided font's TTF file

Question

I'm trying out FTGLES to dynamically display text in arbitrary fonts on OpenGL-ES on iOS (cf. my SO question here). That library seems to require direct access to the TTF file to use the font. Using kosher methods, can one directly access -- by path -- the system font files on iOS? I've RTFM'd and couldn't find anything.

Barring that, does anyone know if it is Apple-approved to copy the system fonts into your app (before submission).

Answer 1

My solution was inspired by skia.

Though cannot access system built-in font files directly, we still have an indirect way:

Create a CGFont with your wanted font name, all contents of SFNT table of this CGFont can be accessed by simply calling CGFontCopyTableTags() and CGFontCopyTableForTag().

A ttf/otf font data can then be constructed by using these tables, save the new created font to disk, you can use it in FTGL ES later.