"""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
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