PLAIN = 'plain'
+RGB = 'rgb'
+SRGB = 'srgb'
+YUV = 'yuv'
+ZS = 'zs'
-class Type:
- '''Describe the type of a color channel.'''
+
+def is_pot(x):
+ return (x & (x - 1)) == 0;
+
+
+VERY_LARGE = 99999999999999999999999
+
+
+class Channel:
+ '''Describe the channel of a color channel.'''
- def __init__(self, kind, norm, size):
- self.kind = kind
+ def __init__(self, type, norm, size, name = ''):
+ self.type = type
self.norm = norm
self.size = size
- self.sign = kind in (SIGNED, FIXED, FLOAT)
+ self.sign = type in (SIGNED, FIXED, FLOAT)
+ self.name = name
def __str__(self):
- s = str(self.kind)
+ s = str(self.type)
if self.norm:
s += 'n'
s += str(self.size)
return s
def __eq__(self, other):
- return self.kind == other.kind and self.norm == other.norm and self.size == other.size
+ return self.type == other.type and self.norm == other.norm and self.size == other.size
+
+ def max(self):
+ '''Maximum representable number.'''
+ if self.type == FLOAT:
+ return VERY_LARGE
+ if self.type == FIXED:
+ return (1 << (self.size/2)) - 1
+ if self.norm:
+ return 1
+ if self.type == UNSIGNED:
+ return (1 << self.size) - 1
+ if self.type == SIGNED:
+ return (1 << (self.size - 1)) - 1
+ assert False
+
+ def min(self):
+ '''Minimum representable number.'''
+ if self.type == FLOAT:
+ return -VERY_LARGE
+ if self.type == FIXED:
+ return -(1 << (self.size/2))
+ if self.type == UNSIGNED:
+ return 0
+ if self.norm:
+ return -1
+ if self.type == SIGNED:
+ return -(1 << (self.size - 1))
+ assert False
class Format:
'''Describe a pixel format.'''
- def __init__(self, name, layout, block_width, block_height, in_types, out_swizzle, colorspace):
+ def __init__(self, name, layout, block_width, block_height, channels, swizzles, colorspace):
self.name = name
self.layout = layout
self.block_width = block_width
self.block_height = block_height
- self.in_types = in_types
- self.out_swizzle = out_swizzle
+ self.channels = channels
+ self.swizzles = swizzles
self.name = name
self.colorspace = colorspace
def block_size(self):
size = 0
- for type in self.in_types:
- size += type.size
+ for channel in self.channels:
+ size += channel.size
return size
def nr_channels(self):
nr_channels = 0
- for type in self.in_types:
- if type.size:
+ for channel in self.channels:
+ if channel.size:
nr_channels += 1
return nr_channels
def is_array(self):
- ref_type = self.in_types[0]
- for type in self.in_types[1:]:
- if type.size and (type.size != ref_type.size or type.size % 8):
+ if self.layout != PLAIN:
+ return False
+ ref_channel = self.channels[0]
+ for channel in self.channels[1:]:
+ if channel.size and (channel.size != ref_channel.size or channel.size % 8):
return False
return True
def is_mixed(self):
- ref_type = self.in_types[0]
- for type in self.in_types[1:]:
- if type.kind != VOID:
- if type.kind != ref_type.kind:
+ if self.layout != PLAIN:
+ return False
+ ref_channel = self.channels[0]
+ if ref_channel.type == VOID:
+ ref_channel = self.channels[1]
+ for channel in self.channels[1:]:
+ if channel.type != VOID:
+ if channel.type != ref_channel.type:
return True
- if type.norm != ref_type.norm:
+ if channel.norm != ref_channel.norm:
return True
return False
+ def is_pot(self):
+ return is_pot(self.block_size())
+
+ def is_int(self):
+ if self.layout != PLAIN:
+ return False
+ for channel in self.channels:
+ if channel.type not in (VOID, UNSIGNED, SIGNED):
+ return False
+ return True
+
+ def is_float(self):
+ if self.layout != PLAIN:
+ return False
+ for channel in self.channels:
+ if channel.type not in (VOID, FLOAT):
+ return False
+ return True
+
+ def is_bitmask(self):
+ if self.layout != PLAIN:
+ return False
+ if self.block_size() not in (8, 16, 32):
+ return False
+ for channel in self.channels:
+ if channel.type not in (VOID, UNSIGNED, SIGNED):
+ return False
+ return True
+
+ def inv_swizzles(self):
+ '''Return an array[4] of inverse swizzle terms'''
+ inv_swizzle = [None]*4
+ for i in range(4):
+ swizzle = self.swizzles[i]
+ if swizzle < 4:
+ inv_swizzle[swizzle] = i
+ return inv_swizzle
+
def stride(self):
return self.block_size()/8
-_kind_parse_map = {
+_type_parse_map = {
'': VOID,
'x': VOID,
'u': UNSIGNED,
def parse(filename):
'''Parse the format descrition in CSV format in terms of the
- Type and Format classes above.'''
+ Channel and Format classes above.'''
stream = open(filename)
formats = []
line = line.strip()
if not line:
continue
+
fields = [field.strip() for field in line.split(',')]
+
name = fields[0]
layout = fields[1]
block_width, block_height = map(int, fields[2:4])
- in_types = []
- for field in fields[4:8]:
+
+ swizzles = [_swizzle_parse_map[swizzle] for swizzle in fields[8]]
+ colorspace = fields[9]
+
+ if layout == PLAIN:
+ names = ['']*4
+ if colorspace in (RGB, SRGB):
+ for i in range(4):
+ swizzle = swizzles[i]
+ if swizzle < 4:
+ names[swizzle] += 'rgba'[i]
+ elif colorspace == ZS:
+ for i in range(4):
+ swizzle = swizzles[i]
+ if swizzle < 4:
+ names[swizzle] += 'zs'[i]
+ else:
+ assert False
+ for i in range(4):
+ if names[i] == '':
+ names[i] = 'x'
+ else:
+ names = ['x', 'y', 'z', 'w']
+
+ channels = []
+ for i in range(0, 4):
+ field = fields[4 + i]
if field:
- kind = _kind_parse_map[field[0]]
+ type = _type_parse_map[field[0]]
if field[1] == 'n':
norm = True
size = int(field[2:])
norm = False
size = int(field[1:])
else:
- kind = VOID
+ type = VOID
norm = False
size = 0
- in_type = Type(kind, norm, size)
- in_types.append(in_type)
- out_swizzle = [_swizzle_parse_map[swizzle] for swizzle in fields[8]]
- colorspace = fields[9]
- formats.append(Format(name, layout, block_width, block_height, in_types, out_swizzle, colorspace))
+ channel = Channel(type, norm, size, names[i])
+ channels.append(channel)
+
+ format = Format(name, layout, block_width, block_height, channels, swizzles, colorspace)
+ formats.append(format)
return formats
projects / mesa.git / blobdiff