Add some notes to the readme.

Lib/ufoProcessor/__init__.py

@@ -111,6 +111,9 @@ def getUFOVersion(ufoPath):
     return p.get('formatVersion')
 
 def swapGlyphNames(font, oldName, newName, swapNameExtension = "_______________swap"):
+    # In font swap the glyphs oldName and newName.
+    # Also swap the names in components in order to preserve appearance.
+    # Also swap the names in font groups. 
     if not oldName in font or not newName in font:
         return None
     swapName = oldName + swapNameExtension
@@ -123,7 +126,6 @@ def swapGlyphNames(font, oldName, newName, swapNameExtension = "_______________s
     font[oldName].drawPoints(p)
     font[swapName].width = font[oldName].width
     # lib?
-
     font[oldName].clear()
     p = font[oldName].getPointPen()
     font[newName].drawPoints(p)
@@ -186,6 +188,7 @@ def swapGlyphNames(font, oldName, newName, swapNameExtension = "_______________s
     for r in remove:
         del font[r]
 
+
 class DecomposePointPen(object):
 
     def __init__(self, glyphSet, outPointPen):

README.md

@@ -1,5 +1,19 @@
 # ufoProcessor
-Python package based on the **designSpaceDocument** (now fontTools.designSpaceLib) specifically to process and generate UFO files.
+Python package based on the **designSpaceDocument** (now [fontTools.designspaceLib](https://github.com/fonttools/fonttools/tree/master/Lib/fontTools/designspaceLib)) specifically to process and generate UFO files.
 
-When the dust of the move has settled I'll make the remove `designSpaceDocument.py` and point to the current file at fontTools. In the mean time and for the sake of continuity (and keeping some things running) it is here.
+* Collect source materials
+* Provide Mutators for specific glyphs, font info, kerning so that other tools can generate partial instances.
+* Generate actual UFO instances in formats 2 and 3.
+* Round geometry as requested
+* Try to stay up to date with fontTools
+* 
+
+## Usage
+The easiest way to use ufoProcessor is to call `build(designspacePath)`
+
+* documentPath: path to the designspace file.
+* outputUFOFormatVersion: integer, 2, 3. Format for generated UFOs. Note: can be different from source UFO format.
+* roundGeometry: bool, if the geometry needs to be rounded to whole integers.
+* processRules: bool, execute designspace rules as swaps.
+* logger: optional logger object.