[cffLib] Recalc CFF's FontBBox when compiling

Lib/fontTools/cffLib/__init__.py

@@ -4,6 +4,7 @@ from __future__ import print_function, division, absolute_import
 from fontTools.misc.py23 import *
 from fontTools.misc import sstruct
 from fontTools.misc import psCharStrings
+from fontTools.misc.arrayTools import unionRect
 from fontTools.misc.textTools import safeEval
 from fontTools.ttLib import TTFont
 from fontTools.ttLib.tables.otBase import OTTableWriter
@@ -101,6 +102,11 @@ class CFFFontSet(object):
 			# use current 'major' value to determine output format
 			assert self.major in (1, 2), "Unknown CFF format"
 			isCFF2 = self.major == 2
+
+		if otFont.recalcBBoxes and not isCFF2:
+			for topDict in self.topDictIndex:
+				topDict.recalcFontBBox()
+
 		if not isCFF2:
 			strings = IndexedStrings()
 		else:
@@ -2313,6 +2319,20 @@ class TopDict(BaseDict):
 				progress.increment(0)  # update
 			i = i + 1
 
+	def recalcFontBBox(self):
+		initialBounds = (float('inf'), float('inf'), float('-inf'), float('-inf'))
+		bounds = initialBounds
+		for charString in self.CharStrings.values():
+			if not hasattr(charString, 'bounds'):
+				charString.recalcBounds()
+			if charString.bounds is not None:
+				bounds = unionRect(bounds, charString.bounds)
+
+		if bounds == initialBounds:
+			self.FontBBox = self.defaults['FontBBox'][:]
+		else:
+			self.FontBBox = [round(v) for v in bounds]
+
 
 class FontDict(BaseDict):
 	#

Tests/cffLib/cffLib_test.py

@@ -0,0 +1,48 @@
+from __future__ import print_function, division, absolute_import
+from fontTools.cffLib import TopDict, PrivateDict, CharStrings
+from fontTools.misc.testTools import parseXML
+import unittest
+
+
+class TopDictTest(unittest.TestCase):
+
+    def test_recalcFontBBox(self):
+        topDict = TopDict()
+        topDict.CharStrings = CharStrings(None, None, None, PrivateDict(), None, None)
+        topDict.CharStrings.fromXML(None, None, parseXML("""
+            <CharString name=".notdef">
+              endchar
+            </CharString>
+            <CharString name="foo"><!-- [100, -100, 300, 100] -->
+              100 -100 rmoveto 200 hlineto 200 vlineto -200 hlineto endchar
+            </CharString>
+            <CharString name="bar"><!-- [0, 0, 200, 200] -->
+              0 0 rmoveto 200 hlineto 200 vlineto -200 hlineto endchar
+            </CharString>
+            <CharString name="baz"><!-- [-55.5, -55.5, 55.5, 55.5] -->
+              -55.5 -55.5 rmoveto 111 hlineto 111 vlineto -111 hlineto endchar
+            </CharString>
+        """))
+
+        topDict.recalcFontBBox()
+        self.assertEqual(topDict.FontBBox, [-56, -100, 300, 200])
+
+    def test_recalcFontBBox_empty(self):
+        topDict = TopDict()
+        topDict.CharStrings = CharStrings(None, None, None, PrivateDict(), None, None)
+        topDict.CharStrings.fromXML(None, None, parseXML("""
+            <CharString name=".notdef">
+              endchar
+            </CharString>
+            <CharString name="space">
+              123 endchar
+            </CharString>
+        """))
+
+        topDict.recalcFontBBox()
+        self.assertEqual(topDict.FontBBox, [0, 0, 0, 0])
+
+
+if __name__ == "__main__":
+    import sys
+    sys.exit(unittest.main())