Substitute glyphs

The font we have for our local script is quite nice but the English letters, numbers, and punctuation are not. Are there XeTeX commands I can add to ptxprint-premods.tex or ptxprint-mods.tex to substitute glyphs? I want to set the font for most of the text to Font A but use the glyphs in Font B for numbers and a few punctuation marks.

I tried using a Fallback Font and adding “0 1 2 3 4 5 6 7 8 9” in the missing characters textbox. But PTXprint fails with a generic “Failed to create” error.

I don’t think you can/should use the fallback-font method, as it does nasty things to all digits, and you don’t want to break s1, q1, etc. I think I’d instead suggest a multi-stage approach:

  1. Specify a different font that does digits nicely for chapters, verses, etc and apply to those styles.
  2. Create a custom character style that specifies that font for in-text numbers.
    e.g. so you get good results for
\s1 The feeding of the \+znum 5000\+znum*
  1. Come up with some changes rules that don’t wrap verse chapter / verse numbers, etc. with \+znum \+znum*, but do wrap other numbers.
  2. I’ve probably forgotten something…