blob: 2df7c0c3956b34f74dce58c2ce30c7f655e0ae8c (
plain) (
blame)
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
|
# -*- python -*-
'''
xpybar – xmobar replacement written in python
Copyright © 2014 Mattias Andrée (maandree@member.fsf.org)
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
'''
import math
import time
def julian_day(t):
'''
Converts a POSIX time timestamp to a Julian Day timestamp
@param t:float The time in POSIX time
@return :float The time in Julian Days
'''
return t / 86400.0 + 2440587.5
def radians(deg):
'''
Convert an angle from degrees to radians
@param deg:float The angle in degrees
@return :float The angle in radians
'''
return deg * math.pi / 180
ref = julian_day(934329600) # 11 August 1999 00:00:00 UTC
now = julian_day(time.time())
synodic_month = 29.530588853
fraction = ((now - ref) / synodic_month) % 1
waxing = fraction <= 0.5 # we get an off by one without equality
print('fraction: %f' % fraction)
print('waxing' if waxing else 'waning')
terminator = 90 - 360 * fraction # sunlit trailing
if terminator < -90:
terminator += 180 # visible side
print('terminator: %f°' % terminator)
hacoversin = lambda deg : 0.5 - math.sin(radians(deg)) / 2
inverted = terminator < 0
illumination = hacoversin(abs(terminator))
if (not waxing) != inverted:
illumination = 1 - illumination
print('illumination: %.2f%%' % (illumination * 100))
|
