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
|
"""Rendering classes and helper functions."""
from __future__ import division, unicode_literals
import color
import random
class Fish(object):
"""Object displayed on the bridge, probably a fish."""
def __init__(self, x, y, width, height, color, step):
"""Create fish with default parameters."""
self.x = x
self.y = y
self.width = width
self.height = height
self.color = color
self.speed = step
self.step = step
def update(self):
"""Swim gently to the other side of the bridge."""
self.x += self.step
class Light(object):
"""Represent a bridge light and its state."""
def __init__(self, x, y, light):
"""Store all facts about a light."""
self.light = light
self.color = color.black
self.transitioning_to = self.color
self.step = 0
self.x = x
self.y = y
def update(self, fish):
"""Change color depending on where the fish is."""
if abs(self.transitioning_to - self.color) < self.step:
self.transitioning_to = pick_HSV().to_RGB()
self.step = (random_change()
* abs(self.color - self.transitioning_to))
new_background = transition(
self.color, self.transitioning_to, self.step
)
coverage = compute_coverage(fish, self.x, self.y)
new_color = coverage * fish.color + (1 - coverage) * new_background
self.light.setRGBRaw(
*map(lambda x: clamp(0, x, 1), new_color.components)
)
class Bridge(object):
"""Store objects on the bridge."""
def __init__(self, lights, fish, rig):
"""Initialize with lights and fish."""
self.lights = lights
self.fish = fish
self.rig = rig
def update(self):
"""Compute fish coverages and push lights to bridge."""
for x, light_col in enumerate(self.lights):
for y, light in enumerate(light_col):
self.fish.update()
light.update(self.fish)
self.rig.updateOnce()
def compute_coverage(fish, x, y):
"""Calculate the coverage of a fish over a box."""
min_x = max(x, fish.x)
max_x = min(x+1, fish.x + fish.width)
min_y = max(y, fish.y)
max_y = min(y+1, fish.y + fish.height)
coverage = (max_x - min_x) * (max_y - min_y)
return coverage
def pick_HSV():
"""Return a random color in an appropriate interval."""
hue = random.random() * (MAX_HUE - MIN_HUE) + MIN_HUE
saturation = random.random()
value = random.random()
return color.HSV(hue, saturation, value)
def transition(start, end, step):
"""Return a vector equal to (end - start) * step + start."""
if start == end:
return start
diff_vector = end - start
step_vector = diff_vector / abs(diff_vector) * step
return step_vector + start
def random_change():
"""Return a random amount that a light should change each frame."""
min_time = int(MIN_TIME * FRAME_RATE)
max_time = int(MAX_TIME * FRAME_RATE)
return 1 / random.randint(min_time, max_time)
def clamp(low, x, high):
"""Return v such that low <= v <= high and |x - v| is minimal."""
return max(low, min(x, high))
|
