src/gallium/auxiliary/util/u_format_parse.py

   1
   2 '''
   3 /**************************************************************************
   4  *
   5  * Copyright 2009 VMware, Inc.
   6  * All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the
  10  * "Software"), to deal in the Software without restriction, including
  11  * without limitation the rights to use, copy, modify, merge, publish,
  12  * distribute, sub license, and/or sell copies of the Software, and to
  13  * permit persons to whom the Software is furnished to do so, subject to
  14  * the following conditions:
  15  *
  16  * The above copyright notice and this permission notice (including the
  17  * next paragraph) shall be included in all copies or substantial portions
  18  * of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  21  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  23  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  24  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  25  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  26  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27  *
  28  **************************************************************************/
  29 '''
  30
  31
  32 from __future__ import division
  33
  34
  35 VOID, UNSIGNED, SIGNED, FIXED, FLOAT = range(5)
  36
  37 SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_W, SWIZZLE_0, SWIZZLE_1, SWIZZLE_NONE, = range(7)
  38
  39 PLAIN = 'plain'
  40
  41 RGB = 'rgb'
  42 SRGB = 'srgb'
  43 YUV = 'yuv'
  44 ZS = 'zs'
  45
  46
  47 def is_pot(x):
  48    return (x & (x - 1)) == 0
  49
  50
  51 VERY_LARGE = 99999999999999999999999
  52
  53
  54 class Channel:
  55     '''Describe the channel of a color channel.'''
  56
  57     def __init__(self, type, norm, pure, size, name = ''):
  58         self.type = type
  59         self.norm = norm
  60         self.pure = pure
  61         self.size = size
  62         self.sign = type in (SIGNED, FIXED, FLOAT)
  63         self.name = name
  64
  65     def __str__(self):
  66         s = str(self.type)
  67         if self.norm:
  68             s += 'n'
  69         if self.pure:
  70             s += 'p'
  71         s += str(self.size)
  72         return s
  73
  74     def __eq__(self, other):
  75         if other is None:
  76             return False
  77
  78         return self.type == other.type and self.norm == other.norm and self.pure == other.pure and self.size == other.size
  79
  80     def __ne__(self, other):
  81         return not self == other
  82
  83     def max(self):
  84         '''Maximum representable number.'''
  85         if self.type == FLOAT:
  86             return VERY_LARGE
  87         if self.type == FIXED:
  88             return (1 << (self.size // 2)) - 1
  89         if self.norm:
  90             return 1
  91         if self.type == UNSIGNED:
  92             return (1 << self.size) - 1
  93         if self.type == SIGNED:
  94             return (1 << (self.size - 1)) - 1
  95         assert False
  96
  97     def min(self):
  98         '''Minimum representable number.'''
  99         if self.type == FLOAT:
 100             return -VERY_LARGE
 101         if self.type == FIXED:
 102             return -(1 << (self.size // 2))
 103         if self.type == UNSIGNED:
 104             return 0
 105         if self.norm:
 106             return -1
 107         if self.type == SIGNED:
 108             return -(1 << (self.size - 1))
 109         assert False
 110
 111
 112 class Format:
 113     '''Describe a pixel format.'''
 114
 115     def __init__(self, name, layout, block_width, block_height, le_channels, le_swizzles, be_channels, be_swizzles, colorspace):
 116         self.name = name
 117         self.layout = layout
 118         self.block_width = block_width
 119         self.block_height = block_height
 120         self.le_channels = le_channels
 121         self.le_swizzles = le_swizzles
 122         self.be_channels = be_channels
 123         self.be_swizzles = be_swizzles
 124         self.name = name
 125         self.colorspace = colorspace
 126
 127     def __str__(self):
 128         return self.name
 129
 130     def short_name(self):
 131         '''Make up a short norm for a format, suitable to be used as suffix in
 132         function names.'''
 133
 134         name = self.name
 135         if name.startswith('PIPE_FORMAT_'):
 136             name = name[len('PIPE_FORMAT_'):]
 137         name = name.lower()
 138         return name
 139
 140     def block_size(self):
 141         size = 0
 142         for channel in self.le_channels:
 143             size += channel.size
 144         return size
 145
 146     def nr_channels(self):
 147         nr_channels = 0
 148         for channel in self.le_channels:
 149             if channel.size:
 150                 nr_channels += 1
 151         return nr_channels
 152
 153     def array_element(self):
 154         if self.layout != PLAIN:
 155             return None
 156         ref_channel = self.le_channels[0]
 157         if ref_channel.type == VOID:
 158            ref_channel = self.le_channels[1]
 159         for channel in self.le_channels:
 160             if channel.size and (channel.size != ref_channel.size or channel.size % 8):
 161                 return None
 162             if channel.type != VOID:
 163                 if channel.type != ref_channel.type:
 164                     return None
 165                 if channel.norm != ref_channel.norm:
 166                     return None
 167                 if channel.pure != ref_channel.pure:
 168                     return None
 169         return ref_channel
 170
 171     def is_array(self):
 172         return self.array_element() != None
 173
 174     def is_mixed(self):
 175         if self.layout != PLAIN:
 176             return False
 177         ref_channel = self.le_channels[0]
 178         if ref_channel.type == VOID:
 179            ref_channel = self.le_channels[1]
 180         for channel in self.le_channels[1:]:
 181             if channel.type != VOID:
 182                 if channel.type != ref_channel.type:
 183                     return True
 184                 if channel.norm != ref_channel.norm:
 185                     return True
 186                 if channel.pure != ref_channel.pure:
 187                     return True
 188         return False
 189
 190     def is_pot(self):
 191         return is_pot(self.block_size())
 192
 193     def is_int(self):
 194         if self.layout != PLAIN:
 195             return False
 196         for channel in self.le_channels:
 197             if channel.type not in (VOID, UNSIGNED, SIGNED):
 198                 return False
 199         return True
 200
 201     def is_float(self):
 202         if self.layout != PLAIN:
 203             return False
 204         for channel in self.le_channels:
 205             if channel.type not in (VOID, FLOAT):
 206                 return False
 207         return True
 208
 209     def is_bitmask(self):
 210         if self.layout != PLAIN:
 211             return False
 212         if self.block_size() not in (8, 16, 32):
 213             return False
 214         for channel in self.le_channels:
 215             if channel.type not in (VOID, UNSIGNED, SIGNED):
 216                 return False
 217         return True
 218
 219     def is_pure_color(self):
 220         if self.layout != PLAIN or self.colorspace == ZS:
 221             return False
 222         pures = [channel.pure
 223                  for channel in self.le_channels
 224                  if channel.type != VOID]
 225         for x in pures:
 226            assert x == pures[0]
 227         return pures[0]
 228
 229     def channel_type(self):
 230         types = [channel.type
 231                  for channel in self.le_channels
 232                  if channel.type != VOID]
 233         for x in types:
 234            assert x == types[0]
 235         return types[0]
 236
 237     def is_pure_signed(self):
 238         return self.is_pure_color() and self.channel_type() == SIGNED
 239
 240     def is_pure_unsigned(self):
 241         return self.is_pure_color() and self.channel_type() == UNSIGNED
 242
 243     def has_channel(self, id):
 244         return self.le_swizzles[id] != SWIZZLE_NONE
 245
 246     def has_depth(self):
 247         return self.colorspace == ZS and self.has_channel(0)
 248
 249     def has_stencil(self):
 250         return self.colorspace == ZS and self.has_channel(1)
 251
 252     def stride(self):
 253         return self.block_size()/8
 254
 255
 256 _type_parse_map = {
 257     '':  VOID,
 258     'x': VOID,
 259     'u': UNSIGNED,
 260     's': SIGNED,
 261     'h': FIXED,
 262     'f': FLOAT,
 263 }
 264
 265 _swizzle_parse_map = {
 266     'x': SWIZZLE_X,
 267     'y': SWIZZLE_Y,
 268     'z': SWIZZLE_Z,
 269     'w': SWIZZLE_W,
 270     '0': SWIZZLE_0,
 271     '1': SWIZZLE_1,
 272     '_': SWIZZLE_NONE,
 273 }
 274
 275 def _parse_channels(fields, layout, colorspace, swizzles):
 276     if layout == PLAIN:
 277         names = ['']*4
 278         if colorspace in (RGB, SRGB):
 279             for i in range(4):
 280                 swizzle = swizzles[i]
 281                 if swizzle < 4:
 282                     names[swizzle] += 'rgba'[i]
 283         elif colorspace == ZS:
 284             for i in range(4):
 285                 swizzle = swizzles[i]
 286                 if swizzle < 4:
 287                     names[swizzle] += 'zs'[i]
 288         else:
 289             assert False
 290         for i in range(4):
 291             if names[i] == '':
 292                 names[i] = 'x'
 293     else:
 294         names = ['x', 'y', 'z', 'w']
 295
 296     channels = []
 297     for i in range(0, 4):
 298         field = fields[i]
 299         if field:
 300             type = _type_parse_map[field[0]]
 301             if field[1] == 'n':
 302                 norm = True
 303                 pure = False
 304                 size = int(field[2:])
 305             elif field[1] == 'p':
 306                 pure = True
 307                 norm = False
 308                 size = int(field[2:])
 309             else:
 310                 norm = False
 311                 pure = False
 312                 size = int(field[1:])
 313         else:
 314             type = VOID
 315             norm = False
 316             pure = False
 317             size = 0
 318         channel = Channel(type, norm, pure, size, names[i])
 319         channels.append(channel)
 320
 321     return channels
 322
 323 def parse(filename):
 324     '''Parse the format description in CSV format in terms of the
 325     Channel and Format classes above.'''
 326
 327     stream = open(filename)
 328     formats = []
 329     for line in stream:
 330         try:
 331             comment = line.index('#')
 332         except ValueError:
 333             pass
 334         else:
 335             line = line[:comment]
 336         line = line.strip()
 337         if not line:
 338             continue
 339
 340         fields = [field.strip() for field in line.split(',')]
 341         if len (fields) == 10:
 342            fields += fields[4:9]
 343         assert len (fields) == 15
 344
 345         name = fields[0]
 346         layout = fields[1]
 347         block_width, block_height = map(int, fields[2:4])
 348         colorspace = fields[9]
 349
 350         le_swizzles = [_swizzle_parse_map[swizzle] for swizzle in fields[8]]
 351         le_channels = _parse_channels(fields[4:8], layout, colorspace, le_swizzles)
 352
 353         be_swizzles = [_swizzle_parse_map[swizzle] for swizzle in fields[14]]
 354         be_channels = _parse_channels(fields[10:14], layout, colorspace, be_swizzles)
 355
 356         le_shift = 0
 357         for channel in le_channels:
 358             channel.shift = le_shift
 359             le_shift += channel.size
 360
 361         be_shift = 0
 362         for channel in be_channels[3::-1]:
 363             channel.shift = be_shift
 364             be_shift += channel.size
 365
 366         assert le_shift == be_shift
 367         for i in range(4):
 368             assert (le_swizzles[i] != SWIZZLE_NONE) == (be_swizzles[i] != SWIZZLE_NONE)
 369
 370         format = Format(name, layout, block_width, block_height, le_channels, le_swizzles, be_channels, be_swizzles, colorspace)
 371         formats.append(format)
 372     return formats
 373