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      1 #!/usr/bin/env python
      2 
      3 '''
      4 /**************************************************************************
      5  *
      6  * Copyright 2009 VMware, Inc.
      7  * All Rights Reserved.
      8  *
      9  * Permission is hereby granted, free of charge, to any person obtaining a
     10  * copy of this software and associated documentation files (the
     11  * "Software"), to deal in the Software without restriction, including
     12  * without limitation the rights to use, copy, modify, merge, publish,
     13  * distribute, sub license, and/or sell copies of the Software, and to
     14  * permit persons to whom the Software is furnished to do so, subject to
     15  * the following conditions:
     16  *
     17  * The above copyright notice and this permission notice (including the
     18  * next paragraph) shall be included in all copies or substantial portions
     19  * of the Software.
     20  *
     21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
     22  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
     24  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
     25  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
     26  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
     27  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     28  *
     29  **************************************************************************/
     30 '''
     31 
     32 
     33 VOID, UNSIGNED, SIGNED, FIXED, FLOAT = range(5)
     34 
     35 SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_W, SWIZZLE_0, SWIZZLE_1, SWIZZLE_NONE, = range(7)
     36 
     37 PLAIN = 'plain'
     38 
     39 RGB = 'rgb'
     40 SRGB = 'srgb'
     41 YUV = 'yuv'
     42 ZS = 'zs'
     43 
     44 
     45 def is_pot(x):
     46    return (x & (x - 1)) == 0
     47 
     48 
     49 VERY_LARGE = 99999999999999999999999
     50 
     51 
     52 class Channel:
     53     '''Describe the channel of a color channel.'''
     54     
     55     def __init__(self, type, norm, pure, size, name = ''):
     56         self.type = type
     57         self.norm = norm
     58         self.pure = pure
     59         self.size = size
     60         self.sign = type in (SIGNED, FIXED, FLOAT)
     61         self.name = name
     62 
     63     def __str__(self):
     64         s = str(self.type)
     65         if self.norm:
     66             s += 'n'
     67         if self.pure:
     68             s += 'p'
     69         s += str(self.size)
     70         return s
     71 
     72     def __eq__(self, other):
     73         return self.type == other.type and self.norm == other.norm and self.pure == other.pure and self.size == other.size
     74 
     75     def max(self):
     76         '''Maximum representable number.'''
     77         if self.type == FLOAT:
     78             return VERY_LARGE
     79         if self.type == FIXED:
     80             return (1 << (self.size/2)) - 1
     81         if self.norm:
     82             return 1
     83         if self.type == UNSIGNED:
     84             return (1 << self.size) - 1
     85         if self.type == SIGNED:
     86             return (1 << (self.size - 1)) - 1
     87         assert False
     88     
     89     def min(self):
     90         '''Minimum representable number.'''
     91         if self.type == FLOAT:
     92             return -VERY_LARGE
     93         if self.type == FIXED:
     94             return -(1 << (self.size/2))
     95         if self.type == UNSIGNED:
     96             return 0
     97         if self.norm:
     98             return -1
     99         if self.type == SIGNED:
    100             return -(1 << (self.size - 1))
    101         assert False
    102 
    103 
    104 class Format:
    105     '''Describe a pixel format.'''
    106 
    107     def __init__(self, name, layout, block_width, block_height, channels, swizzles, colorspace):
    108         self.name = name
    109         self.layout = layout
    110         self.block_width = block_width
    111         self.block_height = block_height
    112         self.channels = channels
    113         self.swizzles = swizzles
    114         self.name = name
    115         self.colorspace = colorspace
    116 
    117     def __str__(self):
    118         return self.name
    119 
    120     def short_name(self):
    121         '''Make up a short norm for a format, suitable to be used as suffix in
    122         function names.'''
    123 
    124         name = self.name
    125         if name.startswith('PIPE_FORMAT_'):
    126             name = name[len('PIPE_FORMAT_'):]
    127         name = name.lower()
    128         return name
    129 
    130     def block_size(self):
    131         size = 0
    132         for channel in self.channels:
    133             size += channel.size
    134         return size
    135 
    136     def nr_channels(self):
    137         nr_channels = 0
    138         for channel in self.channels:
    139             if channel.size:
    140                 nr_channels += 1
    141         return nr_channels
    142 
    143     def is_array(self):
    144         if self.layout != PLAIN:
    145             return False
    146         ref_channel = self.channels[0]
    147         for channel in self.channels[1:]:
    148             if channel.size and (channel.size != ref_channel.size or channel.size % 8):
    149                 return False
    150         return True
    151 
    152     def is_mixed(self):
    153         if self.layout != PLAIN:
    154             return False
    155         ref_channel = self.channels[0]
    156         if ref_channel.type == VOID:
    157            ref_channel = self.channels[1]
    158         for channel in self.channels[1:]:
    159             if channel.type != VOID:
    160                 if channel.type != ref_channel.type:
    161                     return True
    162                 if channel.norm != ref_channel.norm:
    163                     return True
    164                 if channel.pure != ref_channel.pure:
    165                     return True
    166         return False
    167 
    168     def is_pot(self):
    169         return is_pot(self.block_size())
    170 
    171     def is_int(self):
    172         if self.layout != PLAIN:
    173             return False
    174         for channel in self.channels:
    175             if channel.type not in (VOID, UNSIGNED, SIGNED):
    176                 return False
    177         return True
    178 
    179     def is_float(self):
    180         if self.layout != PLAIN:
    181             return False
    182         for channel in self.channels:
    183             if channel.type not in (VOID, FLOAT):
    184                 return False
    185         return True
    186 
    187     def is_bitmask(self):
    188         if self.layout != PLAIN:
    189             return False
    190         if self.block_size() not in (8, 16, 32):
    191             return False
    192         for channel in self.channels:
    193             if channel.type not in (VOID, UNSIGNED, SIGNED):
    194                 return False
    195         return True
    196 
    197     def inv_swizzles(self):
    198         '''Return an array[4] of inverse swizzle terms'''
    199         '''Only pick the first matching value to avoid l8 getting blue and i8 getting alpha'''
    200         inv_swizzle = [None]*4
    201         for i in range(4):
    202             swizzle = self.swizzles[i]
    203             if swizzle < 4 and inv_swizzle[swizzle] == None:
    204                 inv_swizzle[swizzle] = i
    205         return inv_swizzle
    206 
    207     def stride(self):
    208         return self.block_size()/8
    209 
    210 
    211 _type_parse_map = {
    212     '':  VOID,
    213     'x': VOID,
    214     'u': UNSIGNED,
    215     's': SIGNED,
    216     'h': FIXED,
    217     'f': FLOAT,
    218 }
    219 
    220 _swizzle_parse_map = {
    221     'x': SWIZZLE_X,
    222     'y': SWIZZLE_Y,
    223     'z': SWIZZLE_Z,
    224     'w': SWIZZLE_W,
    225     '0': SWIZZLE_0,
    226     '1': SWIZZLE_1,
    227     '_': SWIZZLE_NONE,
    228 }
    229 
    230 def parse(filename):
    231     '''Parse the format descrition in CSV format in terms of the 
    232     Channel and Format classes above.'''
    233 
    234     stream = open(filename)
    235     formats = []
    236     for line in stream:
    237         try:
    238             comment = line.index('#')
    239         except ValueError:
    240             pass
    241         else:
    242             line = line[:comment]
    243         line = line.strip()
    244         if not line:
    245             continue
    246 
    247         fields = [field.strip() for field in line.split(',')]
    248         
    249         name = fields[0]
    250         layout = fields[1]
    251         block_width, block_height = map(int, fields[2:4])
    252 
    253         swizzles = [_swizzle_parse_map[swizzle] for swizzle in fields[8]]
    254         colorspace = fields[9]
    255         
    256         if layout == PLAIN:
    257             names = ['']*4
    258             if colorspace in (RGB, SRGB):
    259                 for i in range(4):
    260                     swizzle = swizzles[i]
    261                     if swizzle < 4:
    262                         names[swizzle] += 'rgba'[i]
    263             elif colorspace == ZS:
    264                 for i in range(4):
    265                     swizzle = swizzles[i]
    266                     if swizzle < 4:
    267                         names[swizzle] += 'zs'[i]
    268             else:
    269                 assert False
    270             for i in range(4):
    271                 if names[i] == '':
    272                     names[i] = 'x'
    273         else:
    274             names = ['x', 'y', 'z', 'w']
    275 
    276         channels = []
    277         for i in range(0, 4):
    278             field = fields[4 + i]
    279             if field:
    280                 type = _type_parse_map[field[0]]
    281                 if field[1] == 'n':
    282                     norm = True
    283                     pure = False
    284                     size = int(field[2:])
    285                 elif field[1] == 'p':
    286                     pure = True
    287                     norm = False
    288                     size = int(field[2:])
    289                 else:
    290                     norm = False
    291                     pure = False
    292                     size = int(field[1:])
    293             else:
    294                 type = VOID
    295                 norm = False
    296                 pure = False
    297                 size = 0
    298             channel = Channel(type, norm, pure, size, names[i])
    299             channels.append(channel)
    300 
    301         format = Format(name, layout, block_width, block_height, channels, swizzles, colorspace)
    302         formats.append(format)
    303     return formats
    304 
    305