Class around PixMap objects that allows more python-like access. By Joe Strout.
diff --git a/Mac/Lib/PixMapWrapper.py b/Mac/Lib/PixMapWrapper.py
new file mode 100644
index 0000000..39e5f8e
--- /dev/null
+++ b/Mac/Lib/PixMapWrapper.py
@@ -0,0 +1,216 @@
+"""PixMapWrapper - defines the PixMapWrapper class, which wraps an opaque
+QuickDraw PixMap data structure in a handy Python class. Also provides
+methods to convert to/from pixel data (from, e.g., the img module) or a
+Python Imaging Library Image object.
+
+J. Strout <joe@strout.net> February 1999"""
+
+import Qd
+import QuickDraw
+import struct
+import MacOS
+import img
+import imgformat
+
+# PixMap data structure element format (as used with struct)
+_pmElemFormat = {
+ 'baseAddr':'l', # address of pixel data
+ 'rowBytes':'h', # bytes per row, plus 0x8000
+ 'bounds':'hhhh', # coordinates imposed over pixel data
+ 'top':'h',
+ 'left':'h',
+ 'bottom':'h',
+ 'right':'h',
+ 'pmVersion':'h', # flags for Color QuickDraw
+ 'packType':'h', # format of compression algorithm
+ 'packSize':'l', # size after compression
+ 'hRes':'l', # horizontal pixels per inch
+ 'vRes':'l', # vertical pixels per inch
+ 'pixelType':'h', # pixel format
+ 'pixelSize':'h', # bits per pixel
+ 'cmpCount':'h', # color components per pixel
+ 'cmpSize':'h', # bits per component
+ 'planeBytes':'l', # offset in bytes to next plane
+ 'pmTable':'l', # handle to color table
+ 'pmReserved':'l' # reserved for future use
+}
+
+# PixMap data structure element offset
+_pmElemOffset = {
+ 'baseAddr':0,
+ 'rowBytes':4,
+ 'bounds':6,
+ 'top':6,
+ 'left':8,
+ 'bottom':10,
+ 'right':12,
+ 'pmVersion':14,
+ 'packType':16,
+ 'packSize':18,
+ 'hRes':22,
+ 'vRes':26,
+ 'pixelType':30,
+ 'pixelSize':32,
+ 'cmpCount':34,
+ 'cmpSize':36,
+ 'planeBytes':38,
+ 'pmTable':42,
+ 'pmReserved':46
+}
+
+class PixMapWrapper:
+ """PixMapWrapper -- wraps the QD PixMap object in a Python class,
+ with methods to easily get/set various pixmap fields. Note: Use the
+ PixMap() method when passing to QD calls."""
+
+ def __init__(self):
+ self.__dict__['data'] = ''
+ self._header = struct.pack("lhhhhhhhlllhhhhlll",
+ id(self.data)+MacOS.string_id_to_buffer,
+ 0, # rowBytes
+ 0, 0, 0, 0, # bounds
+ 0, # pmVersion
+ 0, 0, # packType, packSize
+ 72<<16, 72<<16, # hRes, vRes
+ QuickDraw.RGBDirect, # pixelType
+ 16, # pixelSize
+ 2, 5, # cmpCount, cmpSize,
+ 0, 0, 0) # planeBytes, pmTable, pmReserved
+ self.__dict__['_pm'] = Qd.RawBitMap(self._header)
+
+ def _stuff(self, element, bytes):
+ offset = _pmElemOffset[element]
+ fmt = _pmElemFormat[element]
+ self._header = self._header[:offset] \
+ + struct.pack(fmt, bytes) \
+ + self._header[offset + struct.calcsize(fmt):]
+ self.__dict__['_pm'] = None
+
+ def _unstuff(self, element):
+ offset = _pmElemOffset[element]
+ fmt = _pmElemFormat[element]
+ return struct.unpack(fmt, self._header[offset:offset+struct.calcsize(fmt)])[0]
+
+ def __setattr__(self, attr, val):
+ if attr == 'baseAddr':
+ raise 'UseErr', "don't assign to .baseAddr -- assign to .data instead"
+ elif attr == 'data':
+ self.__dict__['data'] = val
+ self._stuff('baseAddr', id(self.data) + MacOS.string_id_to_buffer)
+ elif attr == 'rowBytes':
+ # high bit is always set for some odd reason
+ self._stuff('rowBytes', val | 0x8000)
+ elif attr == 'bounds':
+ # assume val is in official Left, Top, Right, Bottom order!
+ self._stuff('left',val[0])
+ self._stuff('top',val[1])
+ self._stuff('right',val[2])
+ self._stuff('bottom',val[3])
+ elif attr == 'hRes' or attr == 'vRes':
+ # 16.16 fixed format, so just shift 16 bits
+ self._stuff(attr, int(val) << 16)
+ elif attr in _pmElemFormat.keys():
+ # any other pm attribute -- just stuff
+ self._stuff(attr, val)
+ else:
+ self.__dict__[attr] = val
+
+ def __getattr__(self, attr):
+ if attr == 'rowBytes':
+ # high bit is always set for some odd reason
+ return self._unstuff('rowBytes') & 0x7FFF
+ elif attr == 'bounds':
+ # return bounds in official Left, Top, Right, Bottom order!
+ return ( \
+ self._unstuff('left'),
+ self._unstuff('top'),
+ self._unstuff('right'),
+ self._unstuff('bottom') )
+ elif attr == 'hRes' or attr == 'vRes':
+ # 16.16 fixed format, so just shift 16 bits
+ return self._unstuff(attr) >> 16
+ elif attr in _pmElemFormat.keys():
+ # any other pm attribute -- just unstuff
+ return self._unstuff(attr)
+ else:
+ return self.__dict__[attr]
+
+
+ def PixMap(self):
+ "Return a QuickDraw PixMap corresponding to this data."
+ if not self.__dict__['_pm']:
+ self.__dict__['_pm'] = Qd.RawBitMap(self._header)
+ return self.__dict__['_pm']
+
+ def blit(self, x1=0,y1=0,x2=None,y2=None, port=None):
+ """Draw this pixmap into the given (default current) grafport."""
+ src = self.bounds
+ dest = [x1,y1,x2,y2]
+ if x2 == None:
+ dest[2] = x1 + src[2]-src[0]
+ if y2 == None:
+ dest[3] = y1 + src[3]-src[1]
+ if not port: port = Qd.GetPort()
+ Qd.CopyBits(self.PixMap(), port.portBits, src, tuple(dest),
+ QuickDraw.srcCopy, None)
+
+ def fromstring(self,s,width,height,format=imgformat.macrgb):
+ """Stuff this pixmap with raw pixel data from a string.
+ Supply width, height, and one of the imgformat specifiers."""
+ # we only support 16- and 32-bit mac rgb...
+ # so convert if necessary
+ if format != imgformat.macrgb and format != imgformat.macrgb16:
+ # (LATER!)
+ raise "NotImplementedError", "conversion to macrgb or macrgb16"
+ self.data = s
+ self.bounds = (0,0,width,height)
+ self.cmpCount = 3
+ self.pixelType = QuickDraw.RGBDirect
+ if format == imgformat.macrgb:
+ self.pixelSize = 32
+ self.cmpSize = 8
+ else:
+ self.pixelSize = 16
+ self.cmpSize = 5
+ self.rowBytes = width*self.pixelSize/8
+
+ def tostring(self, format=imgformat.macrgb):
+ """Return raw data as a string in the specified format."""
+ # is the native format requested? if so, just return data
+ if (format == imgformat.macrgb and self.pixelSize == 32) or \
+ (format == imgformat.macrgb16 and self.pixelsize == 16):
+ return self.data
+ # otherwise, convert to the requested format
+ # (LATER!)
+ raise "NotImplementedError", "data format conversion"
+
+ def fromImage(self,im):
+ """Initialize this PixMap from a PIL Image object."""
+ # We need data in ARGB format; PIL can't currently do that,
+ # but it can do RGBA, which we can use by inserting one null
+ # up frontpm =
+ if im.mode != 'RGBA': im = im.convert('RGBA')
+ data = chr(0) + im.tostring()
+ self.fromstring(data, im.size[0], im.size[1])
+
+ def toImage(self):
+ """Return the contents of this PixMap as a PIL Image object."""
+ import Image
+ # our tostring() method returns data in ARGB format,
+ # whereas Image uses RGBA; a bit of slicing fixes this...
+ data = self.tostring()[1:] + chr(0)
+ bounds = self.bounds
+ return Image.fromstring('RGBA',(bounds[2]-bounds[0],bounds[3]-bounds[1]),data)
+
+def test():
+ import MacOS
+ import macfs
+ import Image
+ fsspec, ok = macfs.PromptGetFile("Image File:")
+ if not ok: return
+ path = fsspec.as_pathname()
+ pm = PixMapWrapper()
+ pm.fromImage( Image.open(path) )
+ pm.blit(20,20)
+ return pm
+