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 import sys
  34
  35
  36 VOID, UNSIGNED, SIGNED, FIXED, FLOAT = range(5)
  37
  38 SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_W, SWIZZLE_0, SWIZZLE_1, SWIZZLE_NONE, = range(7)
  39
  40 ARITH = 'arith'
  41 ARRAY = 'array'
  42
  43
  44 class Type:
  45     '''Describe the type of a color channel.'''
  46
  47     def __init__(self, kind, norm, size):
  48         self.kind = kind
  49         self.norm = norm
  50         self.size = size
  51         self.sign = kind in (SIGNED, FIXED, FLOAT)
  52
  53     def __str__(self):
  54         s = str(self.kind)
  55         if self.norm:
  56             s += 'n'
  57         s += str(self.size)
  58         return s
  59
  60     def __eq__(self, other):
  61         return self.kind == other.kind and self.norm == other.norm and self.size == other.size
  62
  63
  64 class Format:
  65     '''Describe a pixel format.'''
  66
  67     def __init__(self, name, layout, block_width, block_height, in_types, out_swizzle, colorspace):
  68         self.name = name
  69         self.layout = layout
  70         self.block_width = block_width
  71         self.block_height = block_height
  72         self.in_types = in_types
  73         self.out_swizzle = out_swizzle
  74         self.name = name
  75         self.colorspace = colorspace
  76
  77     def __str__(self):
  78         return self.name
  79
  80     def block_size(self):
  81         size = 0
  82         for type in self.in_types:
  83             size += type.size
  84         return size
  85
  86     def nr_channels(self):
  87         nr_channels = 0
  88         for type in self.in_types:
  89             if type.size:
  90                 nr_channels += 1
  91         return nr_channels
  92
  93     def is_array(self):
  94         ref_type = self.in_types[0]
  95         for type in self.in_types[1:]:
  96             if type.size and (type.size != ref_type.size or type.size % 8):
  97                 return False
  98         return True
  99
 100     def is_mixed(self):
 101         ref_type = self.in_types[0]
 102         for type in self.in_types[1:]:
 103             if type.kind != VOID:
 104                 if type.kind != ref_type.kind:
 105                     return True
 106                 if type.norm != ref_type.norm:
 107                     return True
 108         return False
 109
 110     def stride(self):
 111         return self.block_size()/8
 112
 113
 114 _kind_parse_map = {
 115     '':  VOID,
 116     'x': VOID,
 117     'u': UNSIGNED,
 118     's': SIGNED,
 119     'h': FIXED,
 120     'f': FLOAT,
 121 }
 122
 123 _swizzle_parse_map = {
 124     'x': SWIZZLE_X,
 125     'y': SWIZZLE_Y,
 126     'z': SWIZZLE_Z,
 127     'w': SWIZZLE_W,
 128     '0': SWIZZLE_0,
 129     '1': SWIZZLE_1,
 130     '_': SWIZZLE_NONE,
 131 }
 132
 133 def parse(filename):
 134     '''Parse the format descrition in CSV format in terms of the
 135     Type and Format classes above.'''
 136
 137     stream = open(filename)
 138     formats = []
 139     for line in stream:
 140         try:
 141             comment = line.index('#')
 142         except ValueError:
 143             pass
 144         else:
 145             line = line[:comment]
 146         line = line.strip()
 147         if not line:
 148             continue
 149         fields = [field.strip() for field in line.split(',')]
 150         name = fields[0]
 151         layout = fields[1]
 152         block_width, block_height = map(int, fields[2:4])
 153         in_types = []
 154         for field in fields[4:8]:
 155             if field:
 156                 kind = _kind_parse_map[field[0]]
 157                 if field[1] == 'n':
 158                     norm = True
 159                     size = int(field[2:])
 160                 else:
 161                     norm = False
 162                     size = int(field[1:])
 163             else:
 164                 kind = VOID
 165                 norm = False
 166                 size = 0
 167             in_type = Type(kind, norm, size)
 168             in_types.append(in_type)
 169         out_swizzle = [_swizzle_parse_map[swizzle] for swizzle in fields[8]]
 170         colorspace = fields[9]
 171         formats.append(Format(name, layout, block_width, block_height, in_types, out_swizzle, colorspace))
 172     return formats
 173