1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
|
# SPDX-License-Identifier: GPL-2.0-or-later
import re
units = {"": 1.0,
"px": 1.0,
"in": 90.0,
"mm": 90.0 / 25.4,
"cm": 90.0 / 2.54,
"pt": 1.25,
"pc": 15.0,
"em": 1.0,
"ex": 1.0,
"INVALID": 1.0, # some DocBook files contain this
}
def srgb_to_linearrgb(c):
if c < 0.04045:
return 0.0 if c < 0.0 else c * (1.0 / 12.92)
else:
return pow((c + 0.055) * (1.0 / 1.055), 2.4)
def check_points_equal(point_a, point_b):
return (abs(point_a[0] - point_b[0]) < 1e-6 and
abs(point_a[1] - point_b[1]) < 1e-6)
match_number = r"-?\d+(\.\d+)?([eE][-+]?\d+)?"
match_first_comma = r"^\s*(?=,)"
match_comma_pair = r",\s*(?=,)"
match_last_comma = r",\s*$"
match_number_optional_parts = r"(-?\d+(\.\d*)?([eE][-+]?\d+)?)|(-?\.\d+([eE][-+]?\d+)?)"
re_match_number_optional_parts = re.compile(match_number_optional_parts)
array_of_floats_pattern = f"({match_number_optional_parts})|{match_first_comma}|{match_comma_pair}|{match_last_comma}"
re_array_of_floats_pattern = re.compile(array_of_floats_pattern)
def parse_array_of_floats(text):
"""
Accepts comma or space separated list of floats (without units) and returns an array
of floating point values.
"""
elements = re_array_of_floats_pattern.findall(text)
return [value_to_float(v[0]) for v in elements]
def read_float(text: str, start_index: int = 0):
"""
Reads floating point value from a string. Parsing starts at the given index.
Returns the value itself (as a string) and index of first character after the value.
"""
n = len(text)
# Skip leading whitespace characters and characters which we consider ignorable for float
# (like values separator).
while start_index < n and (text[start_index].isspace() or text[start_index] == ','):
start_index += 1
if start_index == n:
return "0", start_index
text_part = text[start_index:]
match = re_match_number_optional_parts.match(text_part)
if match is None:
raise Exception('Invalid float value near ' + text[start_index:start_index + 10])
token = match.group(0)
endptr = start_index + match.end(0)
return token, endptr
def parse_coord(coord, size):
"""
Parse coordinate component to common basis
Needed to handle coordinates set in cm, mm, inches.
"""
token, last_char = read_float(coord)
val = float(token)
unit = coord[last_char:].strip() # strip() in case there is a space
if unit == '%':
return float(size) / 100.0 * val
else:
return val * units[unit]
return val
def value_to_float(value_encoded: str):
"""
A simple wrapper around float() which supports empty strings (which are converted to 0).
"""
if len(value_encoded) == 0:
return 0
return float(value_encoded)
|
