File: lists.py

package info (click to toggle)
pyopengl 3.0.1~b2-1
  • links: PTS, VCS
  • area: main
  • in suites: squeeze
  • size: 6,148 kB
  • ctags: 25,165
  • sloc: python: 26,391; sh: 4; makefile: 2
file content (180 lines) | stat: -rw-r--r-- 7,095 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
"""Lists/tuples as data-format for storage

Note:
    This implementation is *far* less efficient than using Numpy
    to support lists/tuples, as the code here is all available in
    C-level code there.  This implementation is required to allow
    for usage without numpy installed.
"""
REGISTRY_NAME = 'ctypesarrays'
import ctypes, _ctypes

from OpenGL import constants, constant, error, ERROR_ON_COPY
from OpenGL.arrays import formathandler
HANDLED_TYPES = (list,tuple)
import operator

def err_on_copy( func ):
    """Decorator which raises informative error if we try to copy while ERROR_ON_COPY"""
    if not ERROR_ON_COPY:
        return func 
    else:
        def raiseErrorOnCopy( self,  value, *args, **named ):
            raise error.CopyError(
                """%s passed, cannot copy with ERROR_ON_COPY set, please use an array type which has native data-pointer support (e.g. numpy or ctypes arrays)"""%( value.__class__.__name__, )
            )
        raiseErrorOnCopy.__name__ = func.__name__
        return raiseErrorOnCopy

class ListHandler( formathandler.FormatHandler ):
    """Storage of array data in Python lists/arrays

    This mechanism, unlike multi-dimensional arrays, is not necessarily
    uniform in type or dimension, so we have to do a lot of extra checks
    to make sure that we get a correctly-structured array.  That, as
    well as the need to copy the arrays in Python code, makes this a far
    less efficient implementation than the numpy implementation, which
    does all the same things, but does them all in C code.

    Note: as an *output* format, this format handler produces ctypes
        arrays, not Python lists, this is done for convenience in coding
        the implementation, mostly.
    """
    @err_on_copy
    def from_param( self, instance, typeCode=None ):
        try:
            return ctypes.byref( instance )
        except TypeError, err:
            array = self.asArray( instance, typeCode )
            pp = ctypes.c_void_p( ctypes.addressof( array ) )
            pp._temporary_array_ = (array,)
            return pp
    dataPointer = staticmethod( ctypes.addressof )
    HANDLED_TYPES = HANDLED_TYPES 
    isOutput = True
    @err_on_copy
    def voidDataPointer( cls, value ):
        """Given value in a known data-pointer type, return void_p for pointer"""
        return ctypes.byref( value )
    def zeros( self, dims, typeCode ):
        """Return array of zeros in given size"""
        type = GL_TYPE_TO_ARRAY_MAPPING[ typeCode ]
        for dim in dims:
            type *= dim 
        return type() # should expicitly set to 0s
    def dimsOf( cls, x ):
        """Calculate total dimension-set of the elements in x
        
        This is *extremely* messy, as it has to track nested arrays
        where the arrays could be different sizes on all sorts of 
        levels...
        """
        try:
            dimensions = [ len(x) ]
        except (TypeError,AttributeError,ValueError), err:
            return []
        else:
            childDimension = None
            for child in x:
                newDimension = cls.dimsOf( child )
                if childDimension is not None:
                    if newDimension != childDimension:
                        raise ValueError( 
                            """Non-uniform array encountered: %s versus %s"""%(
                                newDimension, childDimension,
                            ), x
                        )
    dimsOf = classmethod( dimsOf )

    def arrayToGLType( self, value ):
        """Given a value, guess OpenGL type of the corresponding pointer"""

        result = ARRAY_TO_GL_TYPE_MAPPING.get( value._type_ )
        if result is not None:
            return result
        raise TypeError(
            """Don't know GL type for array of type %r, known types: %s\nvalue:%s"""%(
                value._type_, ARRAY_TO_GL_TYPE_MAPPING.keys(), value,
            )
        )
    def arraySize( self, value, typeCode = None ):
        """Given a data-value, calculate dimensions for the array"""
        dims = 1
        for base in self.types( value ):
            length = getattr( base, '_length_', None)
            if length is not None:
                dims *= length
        return dims 
    def types( self, value ):
        """Produce iterable producing all composite types"""
        dimObject = value
        while dimObject is not None:
            yield dimObject
            dimObject = getattr( dimObject, '_type_', None )
            if isinstance( dimObject, (str,unicode)):
                dimObject = None 
    def dims( self, value ):
        """Produce iterable of all dimensions"""
        for base in self.types( value ):
            length = getattr( base, '_length_', None)
            if length is not None:
                yield length
    @err_on_copy
    def asArray( self, value, typeCode=None ):
        """Convert given value to a ctypes array value of given typeCode
        
        This does a *lot* of work just to get the data into the correct
        format.  It's not going to be anywhere near as fast as a numpy
        or similar approach!
        """
        if typeCode is None:
            raise NotImplementedError( """Haven't implemented type-inference for lists yet""" )
        arrayType = GL_TYPE_TO_ARRAY_MAPPING[ typeCode ]
        if isinstance( value, (list,tuple)):
            subItems = [
                self.asArray( item, typeCode )
                for item in value
            ]
            if subItems:
                for dim in self.dimensions( subItems[0] )[::-1]:
                    arrayType *= dim
                arrayType *= len( subItems )
                result = arrayType()
                result[:] = subItems
                return result
        else:
            return arrayType( value )
    @err_on_copy
    def unitSize( self, value, typeCode=None ):
        """Determine unit size of an array (if possible)"""
        return tuple(self.dims(value))[-1]
    @err_on_copy
    def dimensions( self, value, typeCode=None ):
        """Determine dimensions of the passed array value (if possible)"""
        return tuple( self.dims(value) )


ARRAY_TO_GL_TYPE_MAPPING = {
    constants.GLdouble: constants.GL_DOUBLE,
    constants.GLfloat: constants.GL_FLOAT,
    constants.GLint: constants.GL_INT,
    constants.GLuint: constants.GL_UNSIGNED_INT,
    constants.GLshort: constants.GL_SHORT,
    constants.GLushort: constants.GL_UNSIGNED_SHORT,
        
    constants.GLchar: constants.GL_CHAR,
    constants.GLbyte: constants.GL_BYTE,
    constants.GLubyte: constants.GL_UNSIGNED_BYTE,
}
GL_TYPE_TO_ARRAY_MAPPING = {
    constants.GL_DOUBLE: constants.GLdouble,
    constants.GL_FLOAT: constants.GLfloat,
    constants.GL_INT: constants.GLint,
    constants.GL_UNSIGNED_INT: constants.GLuint,
    constants.GL_SHORT: constants.GLshort,
    constants.GL_UNSIGNED_SHORT: constants.GLushort,
        
    constants.GL_CHAR: constants.GLchar,
    constants.GL_BYTE: constants.GLbyte,
    constants.GL_UNSIGNED_BYTE: constants.GLubyte,
}