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ufomerge

This command line utility and Python library merges together two UFO source format fonts into a single file. It can be used to include glyphs from one font into another font. It takes care of handling:

  • Glyph outlines and information
  • Kerning
  • lib entries
  • Including any needed components
  • "Subsetting" and merging layout rules

Usage

To merge the glyphs of font-b.ufo into font-a.ufo and save as merged.ufo:

$ ufomerge --output merged.ufo font-a.ufo font-b.ufo

To include particular glyphs:

$ ufomerge --output merged.ufo --glyphs alpha,beta,gamma font-a.ufo font-b.ufo

To include glyphs referencing particular Unicode codepoints:

$ ufomerge --output merged.ufo --unicodes 0x03B1,0x03B2,0x03B3 font-a.ufo font-b.ufo

Other useful command line parameters:

  • -G/--glyphs-file: Read the glyphs from a file containing one glyph per line.
  • -U/--codepoints-file: Read the Unicode codepoints from a file containing one codepoint per line.
  • -x/--exclude-glyphs: Stop the given glyphs from being included.
  • -v/--verbose: Be noisier.

What to do about existing glyphs:

  • --skip-existing (the default): If a glyph from font-b already exists in font-a, nothing happens.
  • --replace-existing: If a glyph from font-b already exists in font-a, the new glyph replaces the old one.

What do to about OpenType layout (features.fea). Suppose there is a rule sub A B by C;, and the incoming glyphs are A and B:

  • --subset-layout (the default): the rule is dropped, because C is not part of the target glyphset. The ligature stops working.
  • --layout-closure: C is added to the target glyphset and merged into font-a so the ligature continues to work.
  • --ignore-layout: No layout rules are copied from font-b at all.

Usage as a Python library

ufomerge provides two functions, merge_ufos and subset_ufo. Both take ufoLib2.Font objects, and are documented in their docstrings.

License

This software is licensed under the Apache license. See LICENSE.