Generate fallback Arabic shaping table

Not hooked up yet.

1 files changed, 158 insertions, 62 deletions

diff --git a/src/gen-arabic-table.py b/src/gen-arabic-table.py
index 32bf66cf..6549cb40 100755
--- a/src/gen-arabic-table.py
+++ b/src/gen-arabic-table.py
@@ -1,89 +1,185 @@
 #!/usr/bin/python
 
 import sys
+import os.path
 
-if len (sys.argv) < 2:
-	print >>sys.stderr, "usage: ./gen-arabic-table.py ArabicShaping.txt"
+if len (sys.argv) != 3:
+	print >>sys.stderr, "usage: ./gen-arabic-table.py ArabicShaping.txt UnicodeData.txt"
 	sys.exit (1)
 
-f = file (sys.argv[1])
+files = [file (x) for x in sys.argv[1:]]
 
-header = f.readline (), f.readline ()
-while f.readline ().find ('##################') < 0:
+headers = [[files[0].readline (), files[0].readline ()]]
+headers.append (["UnicodeData.txt does not have a header."])
+while files[0].readline ().find ('##################') < 0:
 	pass
 
 
+def print_joining_table(f):
+
+	print
+	print "static const uint8_t joining_table[] ="
+	print "{"
+
+	min_u = 0x110000
+	max_u = 0
+	num = 0
+	last = -1
+	block = ''
+	for line in f:
+
+		if line[0] == '#':
+			if line.find (" characters"):
+				block = line[2:].strip ()
+			continue
+
+		fields = [x.strip () for x in line.split (';')]
+		if len (fields) == 1:
+			continue
+
+		u = int (fields[0], 16)
+		if u == 0x200C or u == 0x200D:
+			continue
+		if u < last:
+			raise Exception ("Input data character not sorted", u)
+		min_u = min (min_u, u)
+		max_u = max (max_u, u)
+		num += 1
+
+		if block:
+			print "\n  /* %s */\n" % block
+			block = ''
+
+		if last != -1:
+			last += 1
+			while last < u:
+				print "  JOINING_TYPE_X, /* %04X */" % last
+				last += 1
+		else:
+			last = u
+
+		if fields[3] in ["ALAPH", "DALATH RISH"]:
+			value = "JOINING_GROUP_" + fields[3].replace(' ', '_')
+		else:
+			value = "JOINING_TYPE_" + fields[2]
+		print "  %s, /* %s */" % (value, '; '.join(fields))
+
+	print
+	print "};"
+	print
+	print "#define JOINING_TABLE_FIRST	0x%04X" % min_u
+	print "#define JOINING_TABLE_LAST	0x%04X" % max_u
+	print
+
+	occupancy = num * 100 / (max_u - min_u + 1)
+	# Maintain at least 40% occupancy in the table */
+	if occupancy < 40:
+		raise Exception ("Table too sparse, please investigate: ", occupancy)
+
+def print_shaping_table(f):
+
+	shapes = {}
+	ligatures = {}
+	names = {}
+	for line in f:
+
+		fields = [x.strip () for x in line.split (';')]
+		if fields[5][0:1] != '<':
+			continue
+
+		items = fields[5].split (' ')
+		shape, items = items[0][1:-1], tuple (int (x, 16) for x in items[1:])
+
+		if not shape in ['initial', 'medial', 'isolated', 'final']:
+			continue
+
+		c = int (fields[0], 16)
+		if len (items) != 1:
+			# We only care about lam-alef ligatures
+			if len (items) != 2 or items[0] != 0x0644 or items[1] not in [0x0622, 0x0623, 0x0625, 0x0627]:
+				continue
+
+			# Save ligature
+			names[c] = fields[1]
+			if items not in ligatures:
+				ligatures[items] = {}
+			ligatures[items][shape] = c
+			pass
+		else:
+			# Save shape
+			if items[0] not in names:
+				names[items[0]] = fields[1]
+			else:
+				names[items[0]] = os.path.commonprefix ([names[items[0]], fields[1]]).strip ()
+			if items[0] not in shapes:
+				shapes[items[0]] = {}
+			shapes[items[0]][shape] = c
+
+	print
+	print "static const uint16_t shaping_table[][4] ="
+	print "{"
+
+	keys = shapes.keys ()
+	min_u, max_u = min (keys), max (keys)
+	for u in range (min_u, max_u + 1):
+		s = [shapes[u][shape] if u in shapes and shape in shapes[u] else u
+		     for shape in  ['initial', 'medial', 'final', 'isolated']]
+		value = ', '.join ("0x%04X" % c for c in s)
+		print "  {%s}, /* U+%04X %s */" % (value, u, names[u] if u in names else "")
+
+	print "};"
+	print
+	print "#define SHAPING_TABLE_FIRST	0x%04X" % min_u
+	print "#define SHAPING_TABLE_LAST	0x%04X" % max_u
+	print
+
+	print
+	print "static const uint16_t ligature_table[][3] ="
+	print "{"
+
+	ligas = []
+	for pair in ligatures.keys ():
+		for shape in ligatures[pair]:
+			c = ligatures[pair][shape]
+			if shape == 'isolated':
+				liga = (shapes[pair[0]]['initial'], shapes[pair[1]]['final'])
+			elif shape == 'final':
+				liga = (shapes[pair[0]]['medial'], shapes[pair[1]]['final'])
+			else:
+				raise Exception ("Unexpected shape", shape)
+			ligas.append (liga + (c,))
+	ligas.sort ()
+	for liga in ligas:
+		value = ', '.join ("0x%04X" % c for c in liga)
+		print "  {%s}, /* U+%04X %s */" % (value, liga[2], names[liga[2]])
+
+	print "};"
+	print
+
+
+
 print "/* == Start of generated table == */"
 print "/*"
 print " * The following table is generated by running:"
 print " *"
-print " *   ./gen-arabic-table.py ArabicShaping.txt"
+print " *   ./gen-arabic-table.py ArabicShaping.txt UnicodeData.txt"
 print " *"
 print " * on files with these headers:"
 print " *"
-for line in header:
-	print " * %s" % (line.strip())
+for h in headers:
+	for l in h:
+		print " * %s" % (l.strip())
 print " */"
 print
 print "#ifndef HB_OT_SHAPE_COMPLEX_ARABIC_TABLE_HH"
 print "#define HB_OT_SHAPE_COMPLEX_ARABIC_TABLE_HH"
 print
-print "static const uint8_t joining_table[] ="
-print "{"
-
-min_u = 0x110000
-max_u = 0
-num = 0
-last = -1
-block = ''
-for line in f:
-
-	if line[0] == '#':
-		if line.find (" characters"):
-			block = line[2:].strip ()
-		continue
-
-	fields = [x.strip () for x in line.split (';')]
-	if len (fields) == 1:
-		continue
-
-	u = int (fields[0], 16)
-	if u == 0x200C or u == 0x200D:
-		continue
-	if u < last:
-		raise Exception ("Input data character not sorted", u)
-	min_u = min (min_u, u)
-	max_u = max (max_u, u)
-	num += 1
-
-	if block:
-		print "\n  /* %s */\n" % block
-		block = ''
-
-	if last != -1:
-		last += 1
-		while last < u:
-			print "  JOINING_TYPE_X, /* %04X */" % last
-			last += 1
-	else:
-		last = u
-
-	if fields[3] in ["ALAPH", "DALATH RISH"]:
-		value = "JOINING_GROUP_" + fields[3].replace(' ', '_')
-	else:
-		value = "JOINING_TYPE_" + fields[2]
-	print "  %s, /* %s */" % (value, '; '.join(fields))
-print
-print "};"
-print
-print "#define JOINING_TABLE_FIRST	0x%04X" % min_u
-print "#define JOINING_TABLE_LAST	0x%04X" % max_u
+
+print_joining_table (files[0])
+print_shaping_table (files[1])
+
 print
 print "#endif /* HB_OT_SHAPE_COMPLEX_ARABIC_TABLE_HH */"
 print
 print "/* == End of generated table == */"
 
-occupancy = num * 100 / (max_u - min_u + 1)
-# Maintain at least 40% occupancy in the table */
-if occupancy < 40:
-	raise Exception ("Table too sparse, please investigate: ", occupancy)