Merge pull request #2027 from simoncozens/mtilib-docs

Document mtiLib library

Doc/source/mtiLib.rst

@@ -1,8 +1,14 @@
-######
-mtiLib
-######
+###########################################
+mtiLib: Read Monotype FontDame source files
+###########################################
+
+FontTools provides support for reading the OpenType layout tables produced by
+Monotype's FontDame and Font Chef font editors. These tables are written in a
+simple textual format. The ``mtiLib`` library parses these text files and creates
+table objects representing their contents.
+
+Additionally, ``fonttools mtiLib`` will convert a text file to TTX XML.
+
 
 .. automodule:: fontTools.mtiLib
-   :inherited-members:
-   :members:
-   :undoc-members:
+   :members: build, main

Lib/fontTools/mtiLib/__init__.py

@@ -1146,12 +1146,33 @@ class Tokenizer(object):
 		return line
 
 def build(f, font, tableTag=None):
+	"""Convert a Monotype font layout file to an OpenType layout object
+
+	A font object must be passed, but this may be a "dummy" font; it is only
+	used for sorting glyph sets when making coverage tables and to hold the
+	OpenType layout table while it is being built.
+
+	Args:
+		f: A file object.
+		font (TTFont): A font object.
+		tableTag (string): If provided, asserts that the file contains data for the
+			given OpenType table.
+
+	Returns:
+		An object representing the table. (e.g. ``table_G_S_U_B_``)
+	"""
 	lines = Tokenizer(f)
 	return parseTable(lines, font, tableTag=tableTag)
 
 
 def main(args=None, font=None):
-	"""Convert a FontDame OTL file to TTX XML"""
+	"""Convert a FontDame OTL file to TTX XML.
+
+	Writes XML output to stdout.
+
+	Args:
+		args: Command line arguments (``--font``, ``--table``, input files).
+	"""
 	import sys
 	from fontTools import configLogger
 	from fontTools.misc.testTools import MockFont