Add support for character-ID-keyed fonts

[evilpie]

I tried to use this crate for handling DefineFont4 tags, which are OTF fonts, in Adobe Flash SWF files when emulating with ruffle. The current feature set seems almost perfect for us.

However I currently can't use it for drawing, because I get the error "found a character-ID-keyed font, which is not supported yet" from

font/src/formats/opentype/postscript.rs

Line 57 in b1f59a1

_ => raise!("found a character-ID-keyed font, which is not supported yet"),

. It would be nice to use pure rust library for font-parsing, so I would be curious if that is something that might be fixed. I don't really know anything about PostScript yet, so I can't really make sense of this myself.

[IvanUkhov]

Hello, do you have an example of a free font that behaves that way, so one can use it for developing?

[evilpie]

I extracted that font from the flash game MegaMiner using the tool JPEXS. (Under fonts > DefineFont4 (1: MegaMiner...)

It seems to be a modified version of Silkscreen

Note: I now switched to using ttf_parser, so this isn't actually blocking me.