1  # pylint: skip-file
 2  # Remove the above when TTF is actually supported.
 3  
 4  import struct
 5  
 6  
 7  # https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6glyf.html
 8  
 9  
10  class TTF:
11      def __init__(self, f):
12          f.seek(0)
13          self.file = f
14  
15          self.characters = {}
16  
17          def read(format):
18              s = struct.calcsize(format)
19              return struct.unpack_from(format, f.read(s))
20  
21          scalar_type = read(">I")
22          numTables, searchRange, entrySelector, rangeShift = read(">HHHH")
23  
24          print(numTables)
25          table_info = {}
26          for _ in range(numTables):
27              tag, checkSum, offset, length = read(">4sIII")
28              print(tag.decode("utf-8"), hex(checkSum), offset, length)
29              table_info[tag] = (offset, length)
30  
31          head_offset, head_length = table_info[b"head"]
32          f.seek(head_offset)
33          version, fontRevision, checkSumAdjustment, magicNumber = read(">IIII")
34          flags, unitsPerEm, created, modified = read(">HHQQ")
35          xMin, yMin, xMax, yMax = read(">hhhh")
36          print(xMin, yMin, xMax, yMax)
37          macStyle, lowestRecPPEM, fontDirectionHint = read(">HHh")
38          indexToLocFormat, glyphDataFormat = read(">hh")
39  
40          glyf_offset, glyf_length = table_info[b"glyf"]
41          f.seek(glyf_offset)
42          while f.tell() < glyf_offset + glyf_length:
43              numberOfContours, xMin, yMin, xMax, yMax = read(">hhhhh")
44  
45              if numberOfContours > 0:  # Simple
46                  print(numberOfContours)
47                  ends = []
48                  for _ in range(numberOfContours):
49                      ends.append(read(">H"))
50                  instructionLength = read(">h")[0]
51                  instructions = read(">{}s".format(instructionLength))[0]
52                  print(instructions)
53                  break
54              else:
55                  raise RuntimeError("Unsupported font")