no-renumber-glyphs.patch

diff --git a/Lib/fontTools/subset/__init__.py b/Lib/fontTools/subset/__init__.py
index 2ed17cc9..22d1e371 100644
--- a/Lib/fontTools/subset/__init__.py
+++ b/Lib/fontTools/subset/__init__.py
@@ -1719,6 +1719,8 @@ def subset_glyphs(self, s):
 @_add_method(ttLib.getTableClass('hmtx'))
 def subset_glyphs(self, s):
 	self.metrics = _dict_subset(self.metrics, s.glyphs)
+	for g in s.glyphs_emptied:
+		self.metrics[g] = (0,0)
 	return True # Required table
 
 @_add_method(ttLib.getTableClass('hdmx'))
@@ -2063,13 +2065,16 @@ def prune_pre_subset(self, font, options):
 @_add_method(ttLib.getTableClass('glyf'))
 def subset_glyphs(self, s):
 	self.glyphs = _dict_subset(self.glyphs, s.glyphs)
-	indices = [i for i,g in enumerate(self.glyphOrder) if g in s.glyphs]
-	for v in self.glyphs.values():
-		if hasattr(v, "data"):
-			v.remapComponentsFast(indices)
-		else:
-			pass	# No need
-	self.glyphOrder = [g for g in self.glyphOrder if g in s.glyphs]
+	if s.options.renumber_glyphs:
+		indices = [i for i,g in enumerate(self.glyphOrder) if g in s.glyphs]
+		for v in self.glyphs.values():
+			if hasattr(v, "data"):
+				v.remapComponentsFast(indices)
+	Glyph = ttLib.getTableModule('glyf').Glyph
+	for g in s.glyphs_emptied:
+		self.glyphs[g] = Glyph()
+		self.glyphs[g].data = ''
+	self.glyphOrder = [g for g in self.glyphOrder if g in s.glyphs or g in s.glyphs_emptied]
 	# Don't drop empty 'glyf' tables, otherwise 'loca' doesn't get subset.
 	return True
 
@@ -2275,6 +2280,7 @@ class Options(object):
 		self.name_legacy = False
 		self.name_languages = [0x0409] # English
 		self.obfuscate_names = False # to make webfont unusable as a system font
+		self.renumber_glyphs = True
 		self.notdef_glyph = True # gid0 for TrueType / .notdef for CFF
 		self.notdef_outline = False # No need for notdef to have an outline really
 		self.recommended_glyphs = False # gid1, gid2, gid3 for TrueType
@@ -2533,12 +2539,17 @@ class Subsetter(object):
 				log.glyphs(self.glyphs, font=font)
 		self.glyphs_cffed = frozenset(self.glyphs)
 
-		self.glyphs_all = frozenset(self.glyphs)
+		self.glyphs_retained = frozenset(self.glyphs)
+
+		self.glyphs_emptied = frozenset()
+		if not self.options.renumber_glyphs:
+			self.glyphs_emptied = realGlyphs - self.glyphs_retained
+			# TODO Drop empty glyphs at the end of GlyphOrder vector.
 
 		order = font.getReverseGlyphMap()
-		self.reverseOrigGlyphMap = {g:order[g] for g in self.glyphs_all}
+		self.reverseOrigGlyphMap = {g:order[g] for g in self.glyphs_retained}
 
-		log.info("Retaining %d glyphs", len(self.glyphs_all))
+		log.info("Retaining %d glyphs", len(self.glyphs_retained))
 
 		del self.glyphs
 
@@ -2551,7 +2562,7 @@ class Subsetter(object):
 			elif hasattr(clazz, 'subset_glyphs'):
 				with timer("subset '%s'" % tag):
 					table = font[tag]
-					self.glyphs = self.glyphs_all
+					self.glyphs = self.glyphs_retained
 					retain = table.subset_glyphs(self)
 					del self.glyphs
 				if not retain:
@@ -2565,11 +2576,12 @@ class Subsetter(object):
 				log.warning("%s NOT subset; don't know how to subset; dropped", tag)
 				del font[tag]
 
-		with timer("subset GlyphOrder"):
-			glyphOrder = font.getGlyphOrder()
-			glyphOrder = [g for g in glyphOrder if g in self.glyphs_all]
-			font.setGlyphOrder(glyphOrder)
-			font._buildReverseGlyphOrderDict()
+		if self.options.renumber_glyphs:
+			with timer("subset GlyphOrder"):
+				glyphOrder = font.getGlyphOrder()
+				glyphOrder = [g for g in glyphOrder if g in self.glyphs_retained]
+				font.setGlyphOrder(glyphOrder)
+				font._buildReverseGlyphOrderDict()
 
 	def _prune_post_subset(self, font):
 		for tag in font.keys():