Optimized cmap format 4 compile function: now creates more compact binary. The code is horrible, but then again cmap format 4 is beyond horrible...
git-svn-id: svn://svn.code.sf.net/p/fonttools/code/trunk@281 4cde692c-a291-49d1-8350-778aa11640f8
This commit is contained in:
jvr
parent
7bd0d8cdc1
commit
542b9510e6
@ -160,7 +160,6 @@ class cmap_format_0(CmapSubtable):
|
||||
if name <> "map":
|
||||
continue
|
||||
self.cmap[safeEval(attrs["code"])] = attrs["name"]
|
||||
|
||||
|
||||
|
||||
class cmap_format_2(CmapSubtable):
|
||||
@ -183,6 +182,75 @@ cmap_format_4_format = ">7H"
|
||||
#uint16 idRangeOffset[segCount] # Offset in bytes to glyph indexArray, or 0
|
||||
#uint16 glyphIndexArray[variable] # Glyph index array
|
||||
|
||||
def splitRange(startCode, endCode, cmap):
|
||||
if startCode == endCode:
|
||||
return [], [endCode]
|
||||
|
||||
allGlyphs = [(startCode, cmap[startCode])] # XXX
|
||||
lastID = cmap[startCode]
|
||||
lastCode = startCode
|
||||
inOrder = None
|
||||
orderedBegin = None
|
||||
parts = []
|
||||
|
||||
for code in range(startCode + 1, endCode + 1):
|
||||
glyphID = cmap[code]
|
||||
allGlyphs.append((code, glyphID)) # XXX
|
||||
|
||||
if glyphID - 1 == lastID:
|
||||
if inOrder is None or not inOrder:
|
||||
inOrder = 1
|
||||
orderedBegin = lastCode
|
||||
else:
|
||||
if inOrder:
|
||||
inOrder = 0
|
||||
parts.append((orderedBegin, lastCode))
|
||||
orderedBegin = None
|
||||
|
||||
lastID = glyphID
|
||||
lastCode = code
|
||||
|
||||
if inOrder:
|
||||
parts.append((orderedBegin, lastCode))
|
||||
assert lastCode == endCode
|
||||
|
||||
newParts = []
|
||||
for b, e in parts:
|
||||
if b == startCode and e == endCode:
|
||||
break # the whole range, we're fine
|
||||
if b == startCode or e == endCode:
|
||||
threshold = 4 # split costs one more segment
|
||||
else:
|
||||
threshold = 8 # split costs two more segments
|
||||
if (e - b + 1) > threshold:
|
||||
newParts.append((b, e))
|
||||
parts = newParts
|
||||
|
||||
if not parts:
|
||||
return [], [endCode]
|
||||
|
||||
if parts[0][0] != startCode:
|
||||
parts.insert(0, (startCode, parts[0][0] - 1))
|
||||
if parts[-1][1] != endCode:
|
||||
parts.append((parts[-1][1] + 1, endCode))
|
||||
i = 1
|
||||
while i < len(parts):
|
||||
if parts[i-1][1] + 1 != parts[i][0]:
|
||||
parts.insert(i, (parts[i-1][1] + 1, parts[i][0] - 1))
|
||||
i = i + 1
|
||||
i = i + 1
|
||||
|
||||
start = []
|
||||
end = []
|
||||
for b, e in parts:
|
||||
start.append(b)
|
||||
end.append(e)
|
||||
start.pop(0)
|
||||
|
||||
assert len(start) + 1 == len(end)
|
||||
return start, end
|
||||
|
||||
|
||||
class cmap_format_4(CmapSubtable):
|
||||
|
||||
def decompile(self, data, ttFont):
|
||||
@ -190,24 +258,24 @@ class cmap_format_4(CmapSubtable):
|
||||
searchRange, entrySelector, rangeShift) = \
|
||||
struct.unpack(cmap_format_4_format, data[:14])
|
||||
assert len(data) == length, "corrupt cmap table (%d, %d)" % (len(data), length)
|
||||
data = data[14:]
|
||||
segCountX2 = int(segCountX2)
|
||||
segCount = segCountX2 / 2
|
||||
|
||||
allcodes = array.array("H")
|
||||
allcodes.fromstring(data)
|
||||
allCodes = array.array("H")
|
||||
allCodes.fromstring(data[14:])
|
||||
if ttLib.endian <> "big":
|
||||
allcodes.byteswap()
|
||||
allCodes.byteswap()
|
||||
|
||||
# divide the data
|
||||
endCode = allcodes[:segCount]
|
||||
allcodes = allcodes[segCount+1:]
|
||||
startCode = allcodes[:segCount]
|
||||
allcodes = allcodes[segCount:]
|
||||
idDelta = allcodes[:segCount]
|
||||
allcodes = allcodes[segCount:]
|
||||
idRangeOffset = allcodes[:segCount]
|
||||
glyphIndexArray = allcodes[segCount:]
|
||||
endCode = allCodes[:segCount]
|
||||
allCodes = allCodes[segCount+1:] # the +1 is skipping the reservedPad field
|
||||
startCode = allCodes[:segCount]
|
||||
allCodes = allCodes[segCount:]
|
||||
idDelta = allCodes[:segCount]
|
||||
allCodes = allCodes[segCount:]
|
||||
idRangeOffset = allCodes[:segCount]
|
||||
glyphIndexArray = allCodes[segCount:]
|
||||
|
||||
#print ">>>> segCount", segCount, "len(glyphIndexArray):", len(glyphIndexArray), "len(data)", len(data)
|
||||
|
||||
# build 2-byte character mapping
|
||||
cmap = {}
|
||||
@ -229,33 +297,38 @@ class cmap_format_4(CmapSubtable):
|
||||
def compile(self, ttFont):
|
||||
from fontTools.ttLib.sfnt import maxPowerOfTwo
|
||||
|
||||
codes = self.cmap.items()
|
||||
cmap = {} # code:glyphID mapping
|
||||
for code, glyphName in self.cmap.items():
|
||||
cmap[code] = ttFont.getGlyphID(glyphName)
|
||||
codes = cmap.keys()
|
||||
codes.sort()
|
||||
|
||||
# build startCode and endCode lists
|
||||
last = codes[0][0]
|
||||
lastCode = codes[0]
|
||||
endCode = []
|
||||
startCode = [last]
|
||||
for charCode, glyphName in codes[1:]: # skip the first code, it's the first start code
|
||||
if charCode == last + 1:
|
||||
last = charCode
|
||||
startCode = [lastCode]
|
||||
for charCode in codes[1:]: # skip the first code, it's the first start code
|
||||
if charCode == lastCode + 1:
|
||||
lastCode = charCode
|
||||
continue
|
||||
endCode.append(last)
|
||||
start, end = splitRange(startCode[-1], lastCode, cmap)
|
||||
startCode.extend(start)
|
||||
endCode.extend(end)
|
||||
startCode.append(charCode)
|
||||
last = charCode
|
||||
endCode.append(last)
|
||||
lastCode = charCode
|
||||
endCode.append(lastCode)
|
||||
startCode.append(0xffff)
|
||||
endCode.append(0xffff)
|
||||
|
||||
# build up rest of cruft.
|
||||
# build up rest of cruft
|
||||
idDelta = []
|
||||
idRangeOffset = []
|
||||
glyphIndexArray = []
|
||||
|
||||
for i in range(len(endCode)-1): # skip the closing codes (0xffff)
|
||||
indices = []
|
||||
for charCode in range(startCode[i], endCode[i]+1):
|
||||
indices.append(ttFont.getGlyphID(self.cmap[charCode]))
|
||||
for charCode in range(startCode[i], endCode[i] + 1):
|
||||
indices.append(cmap[charCode])
|
||||
if indices == range(indices[0], indices[0] + len(indices)):
|
||||
idDelta.append((indices[0] - startCode[i]) % 0x10000)
|
||||
idRangeOffset.append(0)
|
||||
@ -263,27 +336,31 @@ class cmap_format_4(CmapSubtable):
|
||||
# someone *definitely* needs to get killed.
|
||||
idDelta.append(0)
|
||||
idRangeOffset.append(2 * (len(endCode) + len(glyphIndexArray) - i))
|
||||
glyphIndexArray = glyphIndexArray + indices
|
||||
glyphIndexArray.extend(indices)
|
||||
idDelta.append(1) # 0xffff + 1 == (tadaa!) 0. So this end code maps to .notdef
|
||||
idRangeOffset.append(0)
|
||||
|
||||
# Insane.
|
||||
segCount = len(endCode)
|
||||
segCountX2 = segCount * 2
|
||||
maxexponent = maxPowerOfTwo(segCount)
|
||||
searchRange = 2 * (2 ** maxexponent)
|
||||
entrySelector = maxexponent
|
||||
maxExponent = maxPowerOfTwo(segCount)
|
||||
searchRange = 2 * (2 ** maxExponent)
|
||||
entrySelector = maxExponent
|
||||
rangeShift = 2 * segCount - searchRange
|
||||
|
||||
allcodes = array.array("H",
|
||||
allCodes = array.array("H",
|
||||
endCode + [0] + startCode + idDelta + idRangeOffset + glyphIndexArray)
|
||||
if ttLib.endian <> "big":
|
||||
allcodes.byteswap()
|
||||
data = allcodes.tostring()
|
||||
allCodes.byteswap()
|
||||
data = allCodes.tostring()
|
||||
length = struct.calcsize(cmap_format_4_format) + len(data)
|
||||
header = struct.pack(cmap_format_4_format, self.format, length, self.version,
|
||||
segCountX2, searchRange, entrySelector, rangeShift)
|
||||
return header + data
|
||||
data = header + data
|
||||
|
||||
#print "<<<< segCount", segCount, "len(glyphIndexArray):", len(glyphIndexArray), "len(data)", len(data)
|
||||
|
||||
return data
|
||||
|
||||
def toXML(self, writer, ttFont):
|
||||
from fontTools.unicode import Unicode
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user