Skip to content

Commit 0d3be0a

Browse files
jackjansenjackjansen
committed
Class around PixMap objects that allows more python-like access. By Joe Strout.
1 parent dabcd00 commit 0d3be0a

1 file changed

Lines changed: 216 additions & 0 deletions

File tree

‎Mac/Lib/PixMapWrapper.py‎

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

0 commit comments

Comments
 (0)