Lib/plat-mac/PixMapWrapper.py

   1 """PixMapWrapper - defines the PixMapWrapper class, which wraps an opaque
   2 QuickDraw PixMap data structure in a handy Python class.  Also provides
   3 methods to convert to/from pixel data (from, e.g., the img module) or a
   4 Python Imaging Library Image object.
   5
   6 J. Strout <joe@strout.net>  February 1999"""
   7
   8
   9 from warnings import warnpy3k
  10 warnpy3k("In 3.x, the PixMapWrapper module is removed.", stacklevel=2)
  11
  12 from Carbon import Qd
  13 from Carbon import QuickDraw
  14 import struct
  15 import MacOS
  16 import img
  17 import imgformat
  18
  19 # PixMap data structure element format (as used with struct)
  20 _pmElemFormat = {
  21     'baseAddr':'l',     # address of pixel data
  22     'rowBytes':'H',     # bytes per row, plus 0x8000
  23     'bounds':'hhhh',    # coordinates imposed over pixel data
  24         'top':'h',
  25         'left':'h',
  26         'bottom':'h',
  27         'right':'h',
  28     'pmVersion':'h',    # flags for Color QuickDraw
  29     'packType':'h',     # format of compression algorithm
  30     'packSize':'l',     # size after compression
  31     'hRes':'l',         # horizontal pixels per inch
  32     'vRes':'l',         # vertical pixels per inch
  33     'pixelType':'h',    # pixel format
  34     'pixelSize':'h',    # bits per pixel
  35     'cmpCount':'h',     # color components per pixel
  36     'cmpSize':'h',      # bits per component
  37     'planeBytes':'l',   # offset in bytes to next plane
  38     'pmTable':'l',      # handle to color table
  39     'pmReserved':'l'    # reserved for future use
  40 }
  41
  42 # PixMap data structure element offset
  43 _pmElemOffset = {
  44     'baseAddr':0,
  45     'rowBytes':4,
  46     'bounds':6,
  47         'top':6,
  48         'left':8,
  49         'bottom':10,
  50         'right':12,
  51     'pmVersion':14,
  52     'packType':16,
  53     'packSize':18,
  54     'hRes':22,
  55     'vRes':26,
  56     'pixelType':30,
  57     'pixelSize':32,
  58     'cmpCount':34,
  59     'cmpSize':36,
  60     'planeBytes':38,
  61     'pmTable':42,
  62     'pmReserved':46
  63 }
  64
  65 class PixMapWrapper:
  66     """PixMapWrapper -- wraps the QD PixMap object in a Python class,
  67     with methods to easily get/set various pixmap fields.  Note: Use the
  68     PixMap() method when passing to QD calls."""
  69
  70     def __init__(self):
  71         self.__dict__['data'] = ''
  72         self._header = struct.pack("lhhhhhhhlllhhhhlll",
  73             id(self.data)+MacOS.string_id_to_buffer,
  74             0,                      # rowBytes
  75             0, 0, 0, 0,             # bounds
  76             0,                      # pmVersion
  77             0, 0,                   # packType, packSize
  78             72<<16, 72<<16,         # hRes, vRes
  79             QuickDraw.RGBDirect,    # pixelType
  80             16,                     # pixelSize
  81             2, 5,                   # cmpCount, cmpSize,
  82             0, 0, 0)                # planeBytes, pmTable, pmReserved
  83         self.__dict__['_pm'] = Qd.RawBitMap(self._header)
  84
  85     def _stuff(self, element, bytes):
  86         offset = _pmElemOffset[element]
  87         fmt = _pmElemFormat[element]
  88         self._header = self._header[:offset] \
  89             + struct.pack(fmt, bytes) \
  90             + self._header[offset + struct.calcsize(fmt):]
  91         self.__dict__['_pm'] = None
  92
  93     def _unstuff(self, element):
  94         offset = _pmElemOffset[element]
  95         fmt = _pmElemFormat[element]
  96         return struct.unpack(fmt, self._header[offset:offset+struct.calcsize(fmt)])[0]
  97
  98     def __setattr__(self, attr, val):
  99         if attr == 'baseAddr':
 100             raise 'UseErr', "don't assign to .baseAddr -- assign to .data instead"
 101         elif attr == 'data':
 102             self.__dict__['data'] = val
 103             self._stuff('baseAddr', id(self.data) + MacOS.string_id_to_buffer)
 104         elif attr == 'rowBytes':
 105             # high bit is always set for some odd reason
 106             self._stuff('rowBytes', val | 0x8000)
 107         elif attr == 'bounds':
 108             # assume val is in official Left, Top, Right, Bottom order!
 109             self._stuff('left',val[0])
 110             self._stuff('top',val[1])
 111             self._stuff('right',val[2])
 112             self._stuff('bottom',val[3])
 113         elif attr == 'hRes' or attr == 'vRes':
 114             # 16.16 fixed format, so just shift 16 bits
 115             self._stuff(attr, int(val) << 16)
 116         elif attr in _pmElemFormat.keys():
 117             # any other pm attribute -- just stuff
 118             self._stuff(attr, val)
 119         else:
 120             self.__dict__[attr] = val
 121
 122     def __getattr__(self, attr):
 123         if attr == 'rowBytes':
 124             # high bit is always set for some odd reason
 125             return self._unstuff('rowBytes') & 0x7FFF
 126         elif attr == 'bounds':
 127             # return bounds in official Left, Top, Right, Bottom order!
 128             return ( \
 129                 self._unstuff('left'),
 130                 self._unstuff('top'),
 131                 self._unstuff('right'),
 132                 self._unstuff('bottom') )
 133         elif attr == 'hRes' or attr == 'vRes':
 134             # 16.16 fixed format, so just shift 16 bits
 135             return self._unstuff(attr) >> 16
 136         elif attr in _pmElemFormat.keys():
 137             # any other pm attribute -- just unstuff
 138             return self._unstuff(attr)
 139         else:
 140             return self.__dict__[attr]
 141
 142
 143     def PixMap(self):
 144         "Return a QuickDraw PixMap corresponding to this data."
 145         if not self.__dict__['_pm']:
 146             self.__dict__['_pm'] = Qd.RawBitMap(self._header)
 147         return self.__dict__['_pm']
 148
 149     def blit(self, x1=0,y1=0,x2=None,y2=None, port=None):
 150         """Draw this pixmap into the given (default current) grafport."""
 151         src = self.bounds
 152         dest = [x1,y1,x2,y2]
 153         if x2 is None:
 154             dest[2] = x1 + src[2]-src[0]
 155         if y2 is None:
 156             dest[3] = y1 + src[3]-src[1]
 157         if not port: port = Qd.GetPort()
 158         Qd.CopyBits(self.PixMap(), port.GetPortBitMapForCopyBits(), src, tuple(dest),
 159                 QuickDraw.srcCopy, None)
 160
 161     def fromstring(self,s,width,height,format=imgformat.macrgb):
 162         """Stuff this pixmap with raw pixel data from a string.
 163         Supply width, height, and one of the imgformat specifiers."""
 164         # we only support 16- and 32-bit mac rgb...
 165         # so convert if necessary
 166         if format != imgformat.macrgb and format != imgformat.macrgb16:
 167             # (LATER!)
 168             raise "NotImplementedError", "conversion to macrgb or macrgb16"
 169         self.data = s
 170         self.bounds = (0,0,width,height)
 171         self.cmpCount = 3
 172         self.pixelType = QuickDraw.RGBDirect
 173         if format == imgformat.macrgb:
 174             self.pixelSize = 32
 175             self.cmpSize = 8
 176         else:
 177             self.pixelSize = 16
 178             self.cmpSize = 5
 179         self.rowBytes = width*self.pixelSize/8
 180
 181     def tostring(self, format=imgformat.macrgb):
 182         """Return raw data as a string in the specified format."""
 183         # is the native format requested?  if so, just return data
 184         if (format == imgformat.macrgb and self.pixelSize == 32) or \
 185            (format == imgformat.macrgb16 and self.pixelsize == 16):
 186             return self.data
 187         # otherwise, convert to the requested format
 188         # (LATER!)
 189             raise "NotImplementedError", "data format conversion"
 190
 191     def fromImage(self,im):
 192         """Initialize this PixMap from a PIL Image object."""
 193         # We need data in ARGB format; PIL can't currently do that,
 194         # but it can do RGBA, which we can use by inserting one null
 195         # up frontpm =
 196         if im.mode != 'RGBA': im = im.convert('RGBA')
 197         data = chr(0) + im.tostring()
 198         self.fromstring(data, im.size[0], im.size[1])
 199
 200     def toImage(self):
 201         """Return the contents of this PixMap as a PIL Image object."""
 202         import Image
 203         # our tostring() method returns data in ARGB format,
 204         # whereas Image uses RGBA; a bit of slicing fixes this...
 205         data = self.tostring()[1:] + chr(0)
 206         bounds = self.bounds
 207         return Image.fromstring('RGBA',(bounds[2]-bounds[0],bounds[3]-bounds[1]),data)
 208
 209 def test():
 210     import MacOS
 211     import EasyDialogs
 212     import Image
 213     path = EasyDialogs.AskFileForOpen("Image File:")
 214     if not path: return
 215     pm = PixMapWrapper()
 216     pm.fromImage( Image.open(path) )
 217     pm.blit(20,20)
 218     return pm