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A bridge between UFOs and FontTools.

Project description

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ufo2ft (“UFO to FontTools”) is a fork of ufo2fdk whose goal is to generate OpenType font binaries from UFOs without the FDK dependency.

The library provides two functions, compileOTF and compileTTF, which work exactly the same way:

from defcon import Font
from ufo2ft import compileOTF
ufo = Font('MyFont-Regular.ufo')
otf = compileOTF(ufo)'MyFont-Regular.otf')

In most cases, the behavior of ufo2ft should match that of ufo2fdk, whose documentation is retained below (and hopefully is still accurate).

Naming Data

As with any OpenType compiler, you have to set the font naming data to a particular standard for your naming to be set correctly. In ufo2fdk, you can get away with setting two naming attributes in your object for simple fonts:

  • familyName: The name for your family. For example, “My Garamond”.
  • styleName: The style name for this particular font. For example, “Display Light Italic”

ufo2fdk will create all of the other naming data based on thse two fields. If you want to use the fully automatic naming system, all of the other name attributes should be set to None in your font. However, if you want to override the automated system at any level, you can specify particular naming attributes and ufo2fdk will honor your settings. You don’t have to set all of the attributes, just the ones you don’t want to be automated. For example, in the family “My Garamond” you have eight weights. It would be nice to style map the italics to the romans for each weight. To do this, in the individual romans and italics, you need to set the style mapping data. This is done through the styleMapFamilyName and styleMapStyleName attributes. In each of your roman and italic pairs you would do this:

My Garamond-Light.ufo

  • familyName = “My Garamond”
  • styleName = “Light”
  • styleMapFamilyName = “My Garamond Display Light”
  • styleMapStyleName = “regular”

My Garamond-Light Italic.ufo

  • familyName = “My Garamond”
  • styleName = “Display Light Italic”
  • styleMapFamilyName = “My Garamond Display Light”
  • styleMapStyleName = “italic”

My Garamond-Book.ufo

  • familyName = “My Garamond”
  • styleName = “Book”
  • styleMapFamilyName = “My Garamond Display Book”
  • styleMapStyleName = “regular”

My Garamond-Book Italic.ufo

  • familyName = “My Garamond”
  • styleName = “Display Book Italic”
  • styleMapFamilyName = “My Garamond Display Book”
  • styleMapStyleName = “italic”


Additionally, if you have defined any naming data, or any data for that matter, in table definitions within your font’s features that data will be honored.

Feature generation

If your font’s features do not contain kerning/mark/mkmk features, ufo2ft will create them based on your font’s kerning/anchor data.

In addition to Adobe OpenType feature files, ufo2ft also supports the MTI/Monotype format. For example, a GPOS table in this format would be stored within the UFO at data/com.github.googlei18n.ufo2ft.mtiFeatures/GPOS.mti.


Most of the fallbacks have static values. To see what is set for these, look at in the source code.

In some cases, the fallback values are dynamically generated from other data in the info object. These are handled internally with functions.

Merging TTX

If the UFO data directory has a com.github.fonttools.ttx folder with TTX files ending with .ttx, these will be merged in the generated font. The index TTX (generated when using using ttx -s) is not required.

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Files for ufo2ft, version 2.24.0
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Filename, size ufo2ft-2.24.0-py2.py3-none-any.whl (86.9 kB) File type Wheel Python version py2.py3 Upload date Hashes View
Filename, size (334.4 kB) File type Source Python version None Upload date Hashes View

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