fix broken packs/unpacks in ttf/png (#819)

pyglet · May 3, 2023 · dbd866f · dbd866f
1 parent 6e895ac
commit dbd866f
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Showing 2 changed files with 9 additions and 9 deletions.
diff --git a/pyglet/extlibs/png.py b/pyglet/extlibs/png.py
@@ -991,7 +991,7 @@ def unpack_rows(rows):
     to being a sequence of bytes.
     """
     for row in rows:
-        fmt = f'!{len(row)}'
+        fmt = f'!{len(row)}H'
         yield bytearray(struct.pack(fmt, *row))
 
 
@@ -1722,7 +1722,7 @@ def _process_bKGD(self, data):
                         "PLTE chunk is required before bKGD chunk.")
                 self.background = struct.unpack('B', data)
             else:
-                self.background = struct.unpack(f"!{self.color_planes}",
+                self.background = struct.unpack(f"!{self.color_planes}H",
                                                 data)
         except struct.error:
             raise FormatError("bKGD chunk has incorrect length.")
@@ -1744,7 +1744,7 @@ def _process_tRNS(self, data):
                     f"tRNS chunk is not valid with colour type {self.color_type}.")
             try:
                 self.transparent = \
-                    struct.unpack(f"!{self.color_planes}", data)
+                    struct.unpack(f"!{self.color_planes}H", data)
             except struct.error:
                 raise FormatError("tRNS chunk has incorrect length.")
 
@@ -1977,7 +1977,7 @@ def itertrns(pixels):
             pixels = itertrns(pixels)
         targetbitdepth = None
         if self.sbit:
-            sbit = struct.unpack(f'{len(self.sbit)}', self.sbit)
+            sbit = struct.unpack(f'{len(self.sbit)}B', self.sbit)
             targetbitdepth = max(sbit)
             if targetbitdepth > info['bitdepth']:
                 raise Error(f'sBIT chunk {sbit!r} exceeds bitdepth {self.bitdepth}')

diff --git a/pyglet/font/ttf.py b/pyglet/font/ttf.py
@@ -367,16 +367,16 @@ def _get_character_map_format4(self, offset):
         # a fuckwit. 
         header = _read_cmap_format4Header(self._data, offset)
         seg_count = header.seg_count_x2 // 2
-        array_size = struct.calcsize(f'>{seg_count}')
-        end_count = self._read_array(f'>{seg_count}',
+        array_size = struct.calcsize(f'>{seg_count}H')
+        end_count = self._read_array(f'>{seg_count}H',
                                      offset + header.size)
-        start_count = self._read_array(f'>{seg_count}',
+        start_count = self._read_array(f'>{seg_count}H',
                                        offset + header.size + array_size + 2)
-        id_delta = self._read_array(f'>{seg_count}',
+        id_delta = self._read_array(f'>{seg_count}H',
                                     offset + header.size + array_size + 2 + array_size)
         id_range_offset_address = \
             offset + header.size + array_size + 2 + array_size + array_size
-        id_range_offset = self._read_array(f'>{seg_count}',
+        id_range_offset = self._read_array(f'>{seg_count}H',
                                            id_range_offset_address)
         character_map = {}
         for i in range(0, seg_count):