Merge pull request #970 from mashabow/cff-bounds-recalc

CFF bounds recalculation

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, intRect
 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 +2319,21 @@ class TopDict(BaseDict):
 				progress.increment(0)  # update
 			i = i + 1
 
+	def recalcFontBBox(self):
+		fontBBox = None
+		for charString in self.CharStrings.values():
+			bounds = charString.calcBounds()
+			if bounds is not None:
+				if fontBBox is not None:
+					fontBBox = unionRect(fontBBox, bounds)
+				else:
+					fontBBox = bounds
+
+		if fontBBox is None:
+			self.FontBBox = self.defaults['FontBBox'][:]
+		else:
+			self.FontBBox = list(intRect(fontBBox))
+
 
 class FontDict(BaseDict):
 	#

Lib/fontTools/misc/psCharStrings.py

@@ -5,6 +5,7 @@ CFF dictionary data and Type1/Type2 CharStrings.
 from __future__ import print_function, division, absolute_import
 from fontTools.misc.py23 import *
 from fontTools.misc.fixedTools import fixedToFloat
+from fontTools.pens.boundsPen import BoundsPen
 import struct
 import logging
 
@@ -977,6 +978,11 @@ class T2CharString(object):
 		extractor.execute(self)
 		self.width = extractor.width
 
+	def calcBounds(self):
+		boundsPen = BoundsPen(None)
+		self.draw(boundsPen)
+		return boundsPen.bounds
+
 	def check_program(self, program, isCFF2=False):
 		if isCFF2:
 			if self.program:

Lib/fontTools/ttLib/__init__.py

@@ -90,9 +90,11 @@ class TTFont(object):
 
 		If the recalcBBoxes argument is false, a number of things will *not*
 		be recalculated upon save/compile:
-			1) glyph bounding boxes
+			1) 'glyf' glyph bounding boxes
-			2) maxp font bounding box
+			2) 'CFF ' font bounding box
-			3) hhea min/max values
+			3) 'head' font bounding box
+			4) 'hhea' min/max values
+			5) 'vhea' min/max values
 		(1) is needed for certain kinds of CJK fonts (ask Werner Lemberg ;-).
 		Additionally, upon importing an TTX file, this option cause glyphs
 		to be compiled right away. This should reduce memory consumption

Lib/fontTools/ttLib/tables/_h_e_a_d.py

@@ -33,7 +33,7 @@ headFormat = """
 
 class table__h_e_a_d(DefaultTable.DefaultTable):
 
-	dependencies = ['maxp', 'loca']
+	dependencies = ['maxp', 'loca', 'CFF ']
 
 	def decompile(self, data, ttFont):
 		dummy, rest = sstruct.unpack2(headFormat, data, self)
@@ -59,6 +59,11 @@ class table__h_e_a_d(DefaultTable.DefaultTable):
 				setattr(self, stamp, value)
 
 	def compile(self, ttFont):
+		if ttFont.recalcBBoxes:
+			# For TT-flavored fonts, xMin, yMin, xMax and yMax are set in table__m_a_x_p.recalc().
+			if 'CFF ' in ttFont:
+				topDict = ttFont['CFF '].cff.topDictIndex[0]
+				self.xMin, self.yMin, self.xMax, self.yMax = topDict.FontBBox
 		if ttFont.recalcTimestamp:
 			self.modified = timestampNow()
 		data = sstruct.pack(headFormat, self)

Lib/fontTools/ttLib/tables/_h_h_e_a.py

@@ -5,6 +5,8 @@ from fontTools.misc.textTools import safeEval
 from fontTools.misc.fixedTools import (
 	ensureVersionIsLong as fi2ve, versionToFixed as ve2fi)
 from . import DefaultTable
+import math
+
 
 hheaFormat = """
 		>  # big endian
@@ -32,30 +34,25 @@ class table__h_h_e_a(DefaultTable.DefaultTable):
 
 	# Note: Keep in sync with table__v_h_e_a
 
-	dependencies = ['hmtx', 'glyf']
+	dependencies = ['hmtx', 'glyf', 'CFF ']
 
 	def decompile(self, data, ttFont):
 		sstruct.unpack(hheaFormat, data, self)
 
 	def compile(self, ttFont):
-		if ttFont.isLoaded('glyf') and ttFont.recalcBBoxes:
+		if ttFont.recalcBBoxes and (ttFont.isLoaded('glyf') or ttFont.isLoaded('CFF ')):
 			self.recalc(ttFont)
 		self.tableVersion = fi2ve(self.tableVersion)
 		return sstruct.pack(hheaFormat, self)
 
 	def recalc(self, ttFont):
 		hmtxTable = ttFont['hmtx']
+		self.advanceWidthMax = max(adv for adv, _ in hmtxTable.metrics.values())
+
+		boundsWidthDict = {}
 		if 'glyf' in ttFont:
 			glyfTable = ttFont['glyf']
-			INFINITY = 100000
-			advanceWidthMax = 0
-			minLeftSideBearing = +INFINITY  # arbitrary big number
-			minRightSideBearing = +INFINITY # arbitrary big number
-			xMaxExtent = -INFINITY          # arbitrary big negative number
-
 			for name in ttFont.getGlyphOrder():
-				width, lsb = hmtxTable[name]
-				advanceWidthMax = max(advanceWidthMax, width)
 				g = glyfTable[name]
 				if g.numberOfContours == 0:
 					continue
@@ -63,25 +60,34 @@ class table__h_h_e_a(DefaultTable.DefaultTable):
 					# Composite glyph without extents set.
 					# Calculate those.
 					g.recalcBounds(glyfTable)
+				boundsWidthDict[name] = g.xMax - g.xMin
+		elif 'CFF ' in ttFont:
+			topDict = ttFont['CFF '].cff.topDictIndex[0]
+			for name in ttFont.getGlyphOrder():
+				cs = topDict.CharStrings[name]
+				bounds = cs.calcBounds()
+				if bounds is not None:
+					boundsWidthDict[name] = math.ceil(bounds[2]) - math.floor(bounds[0])
+
+		if boundsWidthDict:
+			minLeftSideBearing = float('inf')
+			minRightSideBearing = float('inf')
+			xMaxExtent = -float('inf')
+			for name, boundsWidth in boundsWidthDict.items():
+				advanceWidth, lsb = hmtxTable[name]
+				rsb = advanceWidth - lsb - boundsWidth
+				extent = lsb + boundsWidth
 				minLeftSideBearing = min(minLeftSideBearing, lsb)
-				rsb = width - lsb - (g.xMax - g.xMin)
 				minRightSideBearing = min(minRightSideBearing, rsb)
-				extent = lsb + (g.xMax - g.xMin)
 				xMaxExtent = max(xMaxExtent, extent)
-
-			if xMaxExtent == -INFINITY:
-				# No glyph has outlines.
-				minLeftSideBearing = 0
-				minRightSideBearing = 0
-				xMaxExtent = 0
-
-			self.advanceWidthMax = advanceWidthMax
 			self.minLeftSideBearing = minLeftSideBearing
 			self.minRightSideBearing = minRightSideBearing
 			self.xMaxExtent = xMaxExtent
-		else:
+
-			# XXX CFF recalc...
+		else:  # No glyph has outlines.
-			pass
+			self.minLeftSideBearing = 0
+			self.minRightSideBearing = 0
+			self.xMaxExtent = 0
 
 	def toXML(self, writer, ttFont):
 		formatstring, names, fixes = sstruct.getformat(hheaFormat)

Lib/fontTools/ttLib/tables/_v_h_e_a.py

@@ -5,6 +5,8 @@ from fontTools.misc.textTools import safeEval
 from fontTools.misc.fixedTools import (
 	ensureVersionIsLong as fi2ve, versionToFixed as ve2fi)
 from . import DefaultTable
+import math
+
 
 vheaFormat = """
 		>	# big endian
@@ -31,30 +33,25 @@ class table__v_h_e_a(DefaultTable.DefaultTable):
 
 	# Note: Keep in sync with table__h_h_e_a
 
-	dependencies = ['vmtx', 'glyf']
+	dependencies = ['vmtx', 'glyf', 'CFF ']
 
 	def decompile(self, data, ttFont):
 		sstruct.unpack(vheaFormat, data, self)
 
 	def compile(self, ttFont):
-		if ttFont.isLoaded('glyf') and ttFont.recalcBBoxes:
+		if ttFont.recalcBBoxes and (ttFont.isLoaded('glyf') or ttFont.isLoaded('CFF ')):
 			self.recalc(ttFont)
 		self.tableVersion = fi2ve(self.tableVersion)
 		return sstruct.pack(vheaFormat, self)
 
 	def recalc(self, ttFont):
-		vtmxTable = ttFont['vmtx']
+		vmtxTable = ttFont['vmtx']
+		self.advanceHeightMax = max(adv for adv, _ in vmtxTable.metrics.values())
+
+		boundsHeightDict = {}
 		if 'glyf' in ttFont:
 			glyfTable = ttFont['glyf']
-			INFINITY = 100000
-			advanceHeightMax = 0
-			minTopSideBearing = +INFINITY    # arbitrary big number
-			minBottomSideBearing = +INFINITY # arbitrary big number
-			yMaxExtent = -INFINITY           # arbitrary big negative number
-
 			for name in ttFont.getGlyphOrder():
-				height, tsb = vtmxTable[name]
-				advanceHeightMax = max(advanceHeightMax, height)
 				g = glyfTable[name]
 				if g.numberOfContours == 0:
 					continue
@@ -62,25 +59,34 @@ class table__v_h_e_a(DefaultTable.DefaultTable):
 					# Composite glyph without extents set.
 					# Calculate those.
 					g.recalcBounds(glyfTable)
+				boundsHeightDict[name] = g.yMax - g.yMin
+		elif 'CFF ' in ttFont:
+			topDict = ttFont['CFF '].cff.topDictIndex[0]
+			for name in ttFont.getGlyphOrder():
+				cs = topDict.CharStrings[name]
+				bounds = cs.calcBounds()
+				if bounds is not None:
+					boundsHeightDict[name] = math.ceil(bounds[3]) - math.floor(bounds[1])
+
+		if boundsHeightDict:
+			minTopSideBearing = float('inf')
+			minBottomSideBearing = float('inf')
+			yMaxExtent = -float('inf')
+			for name, boundsHeight in boundsHeightDict.items():
+				advanceHeight, tsb = vmtxTable[name]
+				bsb = advanceHeight - tsb - boundsHeight
+				extent = tsb + boundsHeight
 				minTopSideBearing = min(minTopSideBearing, tsb)
-				bsb = height - tsb - (g.yMax - g.yMin)
 				minBottomSideBearing = min(minBottomSideBearing, bsb)
-				extent = tsb + (g.yMax - g.yMin)
 				yMaxExtent = max(yMaxExtent, extent)
-
-			if yMaxExtent == -INFINITY:
-				# No glyph has outlines.
-				minTopSideBearing = 0
-				minBottomSideBearing = 0
-				yMaxExtent = 0
-
-			self.advanceHeightMax = advanceHeightMax
 			self.minTopSideBearing = minTopSideBearing
 			self.minBottomSideBearing = minBottomSideBearing
 			self.yMaxExtent = yMaxExtent
-		else:
+
-			# XXX CFF recalc...
+		else:  # No glyph has outlines.
-			pass
+			self.minTopSideBearing = 0
+			self.minBottomSideBearing = 0
+			self.yMaxExtent = 0
 
 	def toXML(self, writer, ttFont):
 		formatstring, names, fixes = sstruct.getformat(vheaFormat)

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"><!-- [-55.1, -55.1, 55.1, 55.1] -->
+              -55.1 -55.1 rmoveto 110.2 hlineto 110.2 vlineto -110.2 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())

Tests/misc/psCharStrings_test.py

@@ -0,0 +1,32 @@
+from __future__ import print_function, division, absolute_import
+from fontTools.cffLib import PrivateDict
+from fontTools.cffLib.specializer import stringToProgram
+from fontTools.misc.psCharStrings import T2CharString
+import unittest
+
+
+class T2CharStringTest(unittest.TestCase):
+
+    @classmethod
+    def stringToT2CharString(cls, string):
+        return T2CharString(program=stringToProgram(string), private=PrivateDict())
+
+    def test_calcBounds_empty(self):
+        cs = self.stringToT2CharString("endchar")
+        bounds = cs.calcBounds()
+        self.assertEqual(bounds, None)
+
+    def test_calcBounds_line(self):
+        cs = self.stringToT2CharString("100 100 rmoveto 40 10 rlineto -20 50 rlineto endchar")
+        bounds = cs.calcBounds()
+        self.assertEqual(bounds, (100, 100, 140, 160))
+
+    def test_calcBounds_curve(self):
+        cs = self.stringToT2CharString("100 100 rmoveto -50 -150 200 0 -50 150 rrcurveto endchar")
+        bounds = cs.calcBounds()
+        self.assertEqual(bounds, (91.90524980688875, -12.5, 208.09475019311125, 100))
+
+
+if __name__ == "__main__":
+    import sys
+    sys.exit(unittest.main())

Tests/ttLib/tables/_h_h_e_a_test.py

@@ -5,8 +5,13 @@ from fontTools.misc.testTools import parseXML, getXML
 from fontTools.misc.textTools import deHexStr
 from fontTools.ttLib import TTFont, newTable
 from fontTools.misc.fixedTools import log
+import os
 import unittest
 
+
+CURR_DIR = os.path.abspath(os.path.dirname(os.path.realpath(__file__)))
+DATA_DIR = os.path.join(CURR_DIR, 'data')
+
 HHEA_DATA = deHexStr(
     '0001 0000 '  # 1.0   version
     '02EE '       # 750   ascent
@@ -155,6 +160,39 @@ class HheaDecompileOrFromXMLTest(unittest.TestCase):
             self.assertEqual(getattr(hhea, key), HHEA_AS_DICT[key])
 
 
+class HheaRecalcTest(unittest.TestCase):
+
+    def test_recalc_TTF(self):
+        font = TTFont()
+        font.importXML(os.path.join(DATA_DIR, '_h_h_e_a_recalc_TTF.ttx'))
+        hhea = font['hhea']
+        hhea.recalc(font)
+        self.assertEqual(hhea.advanceWidthMax, 600)
+        self.assertEqual(hhea.minLeftSideBearing, -56)
+        self.assertEqual(hhea.minRightSideBearing, 100)
+        self.assertEqual(hhea.xMaxExtent, 400)
+
+    def test_recalc_OTF(self):
+        font = TTFont()
+        font.importXML(os.path.join(DATA_DIR, '_h_h_e_a_recalc_OTF.ttx'))
+        hhea = font['hhea']
+        hhea.recalc(font)
+        self.assertEqual(hhea.advanceWidthMax, 600)
+        self.assertEqual(hhea.minLeftSideBearing, -56)
+        self.assertEqual(hhea.minRightSideBearing, 100)
+        self.assertEqual(hhea.xMaxExtent, 400)
+
+    def test_recalc_empty(self):
+        font = TTFont()
+        font.importXML(os.path.join(DATA_DIR, '_h_h_e_a_recalc_empty.ttx'))
+        hhea = font['hhea']
+        hhea.recalc(font)
+        self.assertEqual(hhea.advanceWidthMax, 600)
+        self.assertEqual(hhea.minLeftSideBearing, 0)
+        self.assertEqual(hhea.minRightSideBearing, 0)
+        self.assertEqual(hhea.xMaxExtent, 0)
+
+
 if __name__ == "__main__":
     import sys
     sys.exit(unittest.main())

Tests/ttLib/tables/_v_h_e_a_test.py

@@ -5,8 +5,13 @@ from fontTools.misc.testTools import parseXML, getXML
 from fontTools.misc.textTools import deHexStr
 from fontTools.ttLib import TTFont, newTable
 from fontTools.misc.fixedTools import log
+import os
 import unittest
 
+
+CURR_DIR = os.path.abspath(os.path.dirname(os.path.realpath(__file__)))
+DATA_DIR = os.path.join(CURR_DIR, 'data')
+
 VHEA_DATA_VERSION_11 = deHexStr(
     '0001 1000 '  # 1.1   version
     '01F4 '       # 500   ascent
@@ -232,6 +237,39 @@ class VheaDecompileOrFromXMLTest(unittest.TestCase):
             self.assertEqual(getattr(vhea, key), VHEA_VERSION_11_AS_DICT[key])
 
 
+class VheaRecalcTest(unittest.TestCase):
+
+    def test_recalc_TTF(self):
+        font = TTFont()
+        font.importXML(os.path.join(DATA_DIR, '_v_h_e_a_recalc_TTF.ttx'))
+        vhea = font['vhea']
+        vhea.recalc(font)
+        self.assertEqual(vhea.advanceHeightMax, 900)
+        self.assertEqual(vhea.minTopSideBearing, 200)
+        self.assertEqual(vhea.minBottomSideBearing, 377)
+        self.assertEqual(vhea.yMaxExtent, 312)
+
+    def test_recalc_OTF(self):
+        font = TTFont()
+        font.importXML(os.path.join(DATA_DIR, '_v_h_e_a_recalc_OTF.ttx'))
+        vhea = font['vhea']
+        vhea.recalc(font)
+        self.assertEqual(vhea.advanceHeightMax, 900)
+        self.assertEqual(vhea.minTopSideBearing, 200)
+        self.assertEqual(vhea.minBottomSideBearing, 377)
+        self.assertEqual(vhea.yMaxExtent, 312)
+
+    def test_recalc_empty(self):
+        font = TTFont()
+        font.importXML(os.path.join(DATA_DIR, '_v_h_e_a_recalc_empty.ttx'))
+        vhea = font['vhea']
+        vhea.recalc(font)
+        self.assertEqual(vhea.advanceHeightMax, 900)
+        self.assertEqual(vhea.minTopSideBearing, 0)
+        self.assertEqual(vhea.minBottomSideBearing, 0)
+        self.assertEqual(vhea.yMaxExtent, 0)
+
+
 if __name__ == "__main__":
     import sys
     sys.exit(unittest.main())

Tests/ttLib/tables/data/_h_h_e_a_recalc_OTF.ttx

@@ -0,0 +1,72 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ttFont sfntVersion="OTTO" ttLibVersion="3.12">
+
+  <GlyphOrder>
+    <!-- The 'id' attribute is only for humans; it is ignored when parsed. -->
+    <GlyphID id="0" name=".notdef"/>
+    <GlyphID id="1" name="A"/>
+    <GlyphID id="2" name="B"/>
+    <GlyphID id="3" name="C"/>
+  </GlyphOrder>
+
+  <hhea>
+    <tableVersion value="0x00010000"/>
+    <ascent value="800"/>
+    <descent value="-200"/>
+    <lineGap value="0"/>
+    <advanceWidthMax value="999"/>
+    <minLeftSideBearing value="99"/>
+    <minRightSideBearing value="99"/>
+    <xMaxExtent value="99"/>
+    <caretSlopeRise value="1"/>
+    <caretSlopeRun value="0"/>
+    <caretOffset value="0"/>
+    <reserved0 value="0"/>
+    <reserved1 value="0"/>
+    <reserved2 value="0"/>
+    <reserved3 value="0"/>
+    <metricDataFormat value="0"/>
+    <numberOfHMetrics value="4"/>
+  </hhea>
+
+  <CFF>
+    <major value="1"/>
+    <minor value="0"/>
+    <CFFFont name="Test">
+      <Private>
+      </Private>
+      <CharStrings>
+        <CharString name=".notdef">
+          300
+          0 0 rmoveto
+          1 1 rlineto
+          endchar
+        </CharString>
+        <CharString name="A">
+          400
+          -55.2 -55.2 rmoveto
+          110.4 110.4 rlineto
+          endchar
+        </CharString>
+        <CharString name="B">
+          500
+          100 0 rmoveto
+          300 0 rlineto
+          endchar
+        </CharString>
+        <CharString name="C">
+          600
+          endchar
+        </CharString>
+      </CharStrings>
+    </CFFFont>
+  </CFF>
+
+  <hmtx>
+    <mtx name=".notdef" width="300" lsb="0"/>
+    <mtx name="A" width="400" lsb="-56"/>
+    <mtx name="B" width="500" lsb="100"/>
+    <mtx name="C" width="600" lsb="0"/>
+  </hmtx>
+
+</ttFont>

Tests/ttLib/tables/data/_h_h_e_a_recalc_TTF.ttx

@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ttFont sfntVersion="\x00\x01\x00\x00" ttLibVersion="3.12">
+
+  <GlyphOrder>
+    <!-- The 'id' attribute is only for humans; it is ignored when parsed. -->
+    <GlyphID id="0" name=".notdef"/>
+    <GlyphID id="1" name="A"/>
+    <GlyphID id="2" name="B"/>
+    <GlyphID id="3" name="C"/>
+  </GlyphOrder>
+
+  <hhea>
+    <tableVersion value="0x00010000"/>
+    <ascent value="800"/>
+    <descent value="-200"/>
+    <lineGap value="0"/>
+    <advanceWidthMax value="999"/>
+    <minLeftSideBearing value="99"/>
+    <minRightSideBearing value="99"/>
+    <xMaxExtent value="99"/>
+    <caretSlopeRise value="1"/>
+    <caretSlopeRun value="0"/>
+    <caretOffset value="0"/>
+    <reserved0 value="0"/>
+    <reserved1 value="0"/>
+    <reserved2 value="0"/>
+    <reserved3 value="0"/>
+    <metricDataFormat value="0"/>
+    <numberOfHMetrics value="4"/>
+  </hhea>
+
+  <glyf>
+    <!-- The xMin, yMin, xMax and yMax values
+         will be recalculated by the compiler. -->
+    <TTGlyph name=".notdef" xMin="0" yMin="0" xMax="1" yMax="1">
+      <contour>
+        <pt x="0" y="0" on="1"/>
+        <pt x="1" y="1" on="1"/>
+      </contour>
+    </TTGlyph>
+    <TTGlyph name="A" xMin="-56" yMin="-56" xMax="56" yMax="56">
+      <contour>
+        <pt x="-56" y="-56" on="1"/>
+        <pt x="56" y="56" on="1"/>
+      </contour>
+    </TTGlyph>
+    <TTGlyph name="B" xMin="100" yMin="0" xMax="400" yMax="0">
+      <contour>
+        <pt x="100" y="0" on="1"/>
+        <pt x="400" y="0" on="1"/>
+      </contour>
+    </TTGlyph>
+    <TTGlyph name="C"/><!-- contains no outline data -->
+  </glyf>
+
+  <hmtx>
+    <mtx name=".notdef" width="300" lsb="0"/>
+    <mtx name="A" width="400" lsb="-56"/>
+    <mtx name="B" width="500" lsb="100"/>
+    <mtx name="C" width="600" lsb="0"/>
+  </hmtx>
+
+</ttFont>

Tests/ttLib/tables/data/_h_h_e_a_recalc_empty.ttx

@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ttFont sfntVersion="OTTO" ttLibVersion="3.12">
+
+  <GlyphOrder>
+    <!-- The 'id' attribute is only for humans; it is ignored when parsed. -->
+    <GlyphID id="0" name=".notdef"/>
+    <GlyphID id="1" name="A"/>
+    <GlyphID id="2" name="B"/>
+    <GlyphID id="3" name="C"/>
+  </GlyphOrder>
+
+  <hhea>
+    <tableVersion value="0x00010000"/>
+    <ascent value="800"/>
+    <descent value="-200"/>
+    <lineGap value="0"/>
+    <advanceWidthMax value="999"/>
+    <minLeftSideBearing value="99"/>
+    <minRightSideBearing value="99"/>
+    <xMaxExtent value="99"/>
+    <caretSlopeRise value="1"/>
+    <caretSlopeRun value="0"/>
+    <caretOffset value="0"/>
+    <reserved0 value="0"/>
+    <reserved1 value="0"/>
+    <reserved2 value="0"/>
+    <reserved3 value="0"/>
+    <metricDataFormat value="0"/>
+    <numberOfHMetrics value="4"/>
+  </hhea>
+
+  <CFF>
+    <major value="1"/>
+    <minor value="0"/>
+    <CFFFont name="Test">
+      <Private>
+      </Private>
+      <CharStrings>
+        <CharString name=".notdef">
+          300 endchar
+        </CharString>
+        <CharString name="A">
+          400 endchar
+        </CharString>
+        <CharString name="B">
+          500 endchar
+        </CharString>
+        <CharString name="C">
+          600 endchar
+        </CharString>
+      </CharStrings>
+    </CFFFont>
+  </CFF>
+
+  <hmtx>
+    <mtx name=".notdef" width="300" lsb="0"/>
+    <mtx name="A" width="400" lsb="0"/>
+    <mtx name="B" width="500" lsb="0"/>
+    <mtx name="C" width="600" lsb="0"/>
+  </hmtx>
+
+</ttFont>

Tests/ttLib/tables/data/_v_h_e_a_recalc_OTF.ttx

@@ -0,0 +1,72 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ttFont sfntVersion="OTTO" ttLibVersion="3.12">
+
+  <GlyphOrder>
+    <!-- The 'id' attribute is only for humans; it is ignored when parsed. -->
+    <GlyphID id="0" name=".notdef"/>
+    <GlyphID id="1" name="A"/>
+    <GlyphID id="2" name="B"/>
+    <GlyphID id="3" name="C"/>
+  </GlyphOrder>
+
+  <vhea>
+    <tableVersion value="0x00011000"/>
+    <ascent value="500"/>
+    <descent value="-500"/>
+    <lineGap value="0"/>
+    <advanceHeightMax value="999"/>
+    <minTopSideBearing value="99"/>
+    <minBottomSideBearing value="99"/>
+    <yMaxExtent value="99"/>
+    <caretSlopeRise value="0"/>
+    <caretSlopeRun value="1"/>
+    <caretOffset value="0"/>
+    <reserved1 value="0"/>
+    <reserved2 value="0"/>
+    <reserved3 value="0"/>
+    <reserved4 value="0"/>
+    <metricDataFormat value="0"/>
+    <numberOfVMetrics value="4"/>
+  </vhea>
+
+  <CFF>
+    <major value="1"/>
+    <minor value="0"/>
+    <CFFFont name="Test">
+      <Private>
+      </Private>
+      <CharStrings>
+        <CharString name=".notdef">
+          300
+          0 0 rmoveto
+          1 1 rlineto
+          endchar
+        </CharString>
+        <CharString name="A">
+          400
+          -55.2 -55.2 rmoveto
+          110.4 110.4 rlineto
+          endchar
+        </CharString>
+        <CharString name="B">
+          500
+          100 0 rmoveto
+          300 0 rlineto
+          endchar
+        </CharString>
+        <CharString name="C">
+          600
+          endchar
+        </CharString>
+      </CharStrings>
+    </CFFFont>
+  </CFF>
+
+  <vmtx>
+    <mtx name=".notdef" height="600" tsb="222"/>
+    <mtx name="A" height="700" tsb="200"/>
+    <mtx name="B" height="800" tsb="300"/>
+    <mtx name="C" height="900" tsb="0"/>
+  </vmtx>
+
+</ttFont>

Tests/ttLib/tables/data/_v_h_e_a_recalc_TTF.ttx

@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ttFont sfntVersion="\x00\x01\x00\x00" ttLibVersion="3.12">
+
+  <GlyphOrder>
+    <!-- The 'id' attribute is only for humans; it is ignored when parsed. -->
+    <GlyphID id="0" name=".notdef"/>
+    <GlyphID id="1" name="A"/>
+    <GlyphID id="2" name="B"/>
+    <GlyphID id="3" name="C"/>
+  </GlyphOrder>
+
+  <vhea>
+    <tableVersion value="0x00011000"/>
+    <ascent value="500"/>
+    <descent value="-500"/>
+    <lineGap value="0"/>
+    <advanceHeightMax value="999"/>
+    <minTopSideBearing value="99"/>
+    <minBottomSideBearing value="99"/>
+    <yMaxExtent value="99"/>
+    <caretSlopeRise value="0"/>
+    <caretSlopeRun value="1"/>
+    <caretOffset value="0"/>
+    <reserved1 value="0"/>
+    <reserved2 value="0"/>
+    <reserved3 value="0"/>
+    <reserved4 value="0"/>
+    <metricDataFormat value="0"/>
+    <numberOfVMetrics value="4"/>
+  </vhea>
+
+  <glyf>
+    <!-- The xMin, yMin, xMax and yMax values
+         will be recalculated by the compiler. -->
+    <TTGlyph name=".notdef" xMin="0" yMin="0" xMax="1" yMax="1">
+      <contour>
+        <pt x="0" y="0" on="1"/>
+        <pt x="1" y="1" on="1"/>
+      </contour>
+    </TTGlyph>
+    <TTGlyph name="A" xMin="-56" yMin="-56" xMax="56" yMax="56">
+      <contour>
+        <pt x="-56" y="-56" on="1"/>
+        <pt x="56" y="56" on="1"/>
+      </contour>
+    </TTGlyph>
+    <TTGlyph name="B" xMin="100" yMin="0" xMax="400" yMax="0">
+      <contour>
+        <pt x="100" y="0" on="1"/>
+        <pt x="400" y="0" on="1"/>
+      </contour>
+    </TTGlyph>
+    <TTGlyph name="C"/><!-- contains no outline data -->
+  </glyf>
+
+  <vmtx>
+    <mtx name=".notdef" height="600" tsb="222"/>
+    <mtx name="A" height="700" tsb="200"/>
+    <mtx name="B" height="800" tsb="300"/>
+    <mtx name="C" height="900" tsb="0"/>
+  </vmtx>
+
+</ttFont>

Tests/ttLib/tables/data/_v_h_e_a_recalc_empty.ttx

@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ttFont sfntVersion="OTTO" ttLibVersion="3.12">
+
+  <GlyphOrder>
+    <!-- The 'id' attribute is only for humans; it is ignored when parsed. -->
+    <GlyphID id="0" name=".notdef"/>
+    <GlyphID id="1" name="A"/>
+    <GlyphID id="2" name="B"/>
+    <GlyphID id="3" name="C"/>
+  </GlyphOrder>
+
+  <vhea>
+    <tableVersion value="0x00011000"/>
+    <ascent value="500"/>
+    <descent value="-500"/>
+    <lineGap value="0"/>
+    <advanceHeightMax value="999"/>
+    <minTopSideBearing value="99"/>
+    <minBottomSideBearing value="99"/>
+    <yMaxExtent value="99"/>
+    <caretSlopeRise value="0"/>
+    <caretSlopeRun value="1"/>
+    <caretOffset value="0"/>
+    <reserved1 value="0"/>
+    <reserved2 value="0"/>
+    <reserved3 value="0"/>
+    <reserved4 value="0"/>
+    <metricDataFormat value="0"/>
+    <numberOfVMetrics value="4"/>
+  </vhea>
+
+  <CFF>
+    <major value="1"/>
+    <minor value="0"/>
+    <CFFFont name="Test">
+      <Private>
+      </Private>
+      <CharStrings>
+        <CharString name=".notdef">
+          300 endchar
+        </CharString>
+        <CharString name="A">
+          400 endchar
+        </CharString>
+        <CharString name="B">
+          500 endchar
+        </CharString>
+        <CharString name="C">
+          600 endchar
+        </CharString>
+      </CharStrings>
+    </CFFFont>
+  </CFF>
+
+  <vmtx>
+    <mtx name=".notdef" height="600" tsb="0"/>
+    <mtx name="A" height="700" tsb="0"/>
+    <mtx name="B" height="800" tsb="0"/>
+    <mtx name="C" height="900" tsb="0"/>
+  </vmtx>
+
+</ttFont>