src/gallium/auxiliary/util/u_format_parse.py

   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
  40 class Type:
  41     '''Describe the type of a color channel.'''
  42
  43     def __init__(self, kind, norm, size):
  44         self.kind = kind
  45         self.norm = norm
  46         self.size = size
  47         self.sign = kind in (SIGNED, FIXED, FLOAT)
  48
  49     def __str__(self):
  50         s = str(self.kind)
  51         if self.norm:
  52             s += 'n'
  53         s += str(self.size)
  54         return s
  55
  56     def __eq__(self, other):
  57         return self.kind == other.kind and self.norm == other.norm and self.size == other.size
  58
  59
  60 class Format:
  61     '''Describe a pixel format.'''
  62
  63     def __init__(self, name, layout, block_width, block_height, in_types, out_swizzle, colorspace):
  64         self.name = name
  65         self.layout = layout
  66         self.block_width = block_width
  67         self.block_height = block_height
  68         self.in_types = in_types
  69         self.out_swizzle = out_swizzle
  70         self.name = name
  71         self.colorspace = colorspace
  72
  73     def __str__(self):
  74         return self.name
  75
  76     def short_name(self):
  77         '''Make up a short norm for a format, suitable to be used as suffix in
  78         function names.'''
  79
  80         name = self.name
  81         if name.startswith('PIPE_FORMAT_'):
  82             name = name[len('PIPE_FORMAT_'):]
  83         name = name.lower()
  84         return name
  85
  86     def block_size(self):
  87         size = 0
  88         for type in self.in_types:
  89             size += type.size
  90         return size
  91
  92     def nr_channels(self):
  93         nr_channels = 0
  94         for type in self.in_types:
  95             if type.size:
  96                 nr_channels += 1
  97         return nr_channels
  98
  99     def is_array(self):
 100         ref_type = self.in_types[0]
 101         for type in self.in_types[1:]:
 102             if type.size and (type.size != ref_type.size or type.size % 8):
 103                 return False
 104         return True
 105
 106     def is_mixed(self):
 107         ref_type = self.in_types[0]
 108         for type in self.in_types[1:]:
 109             if type.kind != VOID:
 110                 if type.kind != ref_type.kind:
 111                     return True
 112                 if type.norm != ref_type.norm:
 113                     return True
 114         return False
 115
 116     def stride(self):
 117         return self.block_size()/8
 118
 119
 120 _kind_parse_map = {
 121     '':  VOID,
 122     'x': VOID,
 123     'u': UNSIGNED,
 124     's': SIGNED,
 125     'h': FIXED,
 126     'f': FLOAT,
 127 }
 128
 129 _swizzle_parse_map = {
 130     'x': SWIZZLE_X,
 131     'y': SWIZZLE_Y,
 132     'z': SWIZZLE_Z,
 133     'w': SWIZZLE_W,
 134     '0': SWIZZLE_0,
 135     '1': SWIZZLE_1,
 136     '_': SWIZZLE_NONE,
 137 }
 138
 139 def parse(filename):
 140     '''Parse the format descrition in CSV format in terms of the
 141     Type and Format classes above.'''
 142
 143     stream = open(filename)
 144     formats = []
 145     for line in stream:
 146         try:
 147             comment = line.index('#')
 148         except ValueError:
 149             pass
 150         else:
 151             line = line[:comment]
 152         line = line.strip()
 153         if not line:
 154             continue
 155         fields = [field.strip() for field in line.split(',')]
 156         name = fields[0]
 157         layout = fields[1]
 158         block_width, block_height = map(int, fields[2:4])
 159         in_types = []
 160         for field in fields[4:8]:
 161             if field:
 162                 kind = _kind_parse_map[field[0]]
 163                 if field[1] == 'n':
 164                     norm = True
 165                     size = int(field[2:])
 166                 else:
 167                     norm = False
 168                     size = int(field[1:])
 169             else:
 170                 kind = VOID
 171                 norm = False
 172                 size = 0
 173             in_type = Type(kind, norm, size)
 174             in_types.append(in_type)
 175         out_swizzle = [_swizzle_parse_map[swizzle] for swizzle in fields[8]]
 176         colorspace = fields[9]
 177         formats.append(Format(name, layout, block_width, block_height, in_types, out_swizzle, colorspace))
 178     return formats
 179