Files
2018-04-03 19:38:54 +02:00

208 lines
4.6 KiB
Python

from big_ol_pile_of_manim_imports import *
from once_useful_constructs.combinatorics import *
nb_levels = 50
dev_x_step = 2
dev_y_step = 5
def rainbow_color(alpha):
nb_colors = 100
rainbow = color_gradient([RED, ORANGE, YELLOW, GREEN, BLUE, PURPLE], nb_colors)
rainbow = np.append(rainbow,PURPLE)
index = int(alpha * nb_colors)
return rainbow[index]
class SampleScene(Scene):
def construct(self):
triangle = Polygon()
self.add(triangle)
self.wait()
class PascalNetScene(Scene):
def construct(self):
unit_width = 0.25
top_height = 4.0
level_height = 2.0 * top_height / nb_levels
start_points = np.array([top_height * UP])
dev_start = start_points[0]
j = 0
for n in range(nb_levels):
half_width = 0.5 * (n + 0.5) * unit_width
stop_points_left = start_points.copy()
stop_points_left[:,0] -= 0.5 * unit_width
stop_points_left[:,1] -= level_height
stop_points_right = start_points.copy()
stop_points_right[:,0] += 0.5 * unit_width
stop_points_right[:,1] -= level_height
for (p,q) in zip(start_points,stop_points_left):
alpha = np.abs((p[0]+q[0])/2) / half_width
color = rainbow_color(alpha)
line = Line(p,q, stroke_color = color)
self.add(line)
for (i,(p,q)) in enumerate(zip(start_points,stop_points_right)):
alpha = np.abs((p[0]+q[0])/2) / half_width
color = rainbow_color(alpha)
line = Line(p,q, stroke_color = color)
self.add(line)
if (n + 1) % dev_y_step == 0 and n != 1:
j += dev_x_step
dev_stop = stop_points_left[j]
line = Line(dev_start,dev_stop,stroke_color = WHITE)
self.add(line)
dot = Dot(dev_stop, fill_color = WHITE)
self.add_foreground_mobject(dot)
dev_start = dev_stop
start_points = np.append(stop_points_left,[stop_points_right[-1]], axis = 0)
self.wait()
class RescaledPascalNetScene(Scene):
def construct(self):
half_width = 3.0
top_height = 4.0
level_height = 2.0 * top_height / nb_levels
start_points = np.array([top_height * UP])
left_edge = top_height * UP + half_width * LEFT
right_edge = top_height * UP + half_width * RIGHT
dev_start = start_points[0]
j = 0
for n in range(nb_levels):
if n == 0:
start_points_left_shift = np.array([left_edge])
else:
start_points_left_shift = start_points[:-1]
start_points_left_shift = np.insert(start_points_left_shift,0,left_edge, axis = 0)
stop_points_left = 0.5 * (start_points + start_points_left_shift)
stop_points_left += level_height * DOWN
if n == 0:
start_points_right_shift = np.array([right_edge])
else:
start_points_right_shift = start_points[1:]
start_points_right_shift = np.append(start_points_right_shift,np.array([right_edge]), axis = 0)
stop_points_right = 0.5 * (start_points + start_points_right_shift)
stop_points_right += level_height * DOWN
for (i,(p,q)) in enumerate(zip(start_points,stop_points_left)):
color = LIGHT_GRAY
if n % 2 == 0 and i <= n/2:
m = n/2 + 0.25
jj = i
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
elif n % 2 == 0 and i > n/2:
m = n/2 + 0.25
jj = n - i + 0.5
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
elif n % 2 == 1 and i <= n/2:
m = n/2 + 0.75
jj = i
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
elif n % 2 == 1 and i > n/2:
m = n/2 + 0.75
jj = n - i + 0.5
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
line = Line(p,q, stroke_color = color)
self.add(line)
for (i,(p,q)) in enumerate(zip(start_points,stop_points_right)):
color = LIGHT_GRAY
if n % 2 == 0 and i < n/2:
m = n/2 + 0.25
jj = i + 0.5
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
elif n % 2 == 0 and i >= n/2:
m = n/2 + 0.25
jj = n - i
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
elif n % 2 == 1 and i <= n/2:
m = n/2 + 0.75
jj = i + 0.5
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
elif n % 2 == 1 and i > n/2:
m = n/2 + 0.75
jj = n - i
alpha = 1 - float(jj)/m
color = rainbow_color(alpha)
line = Line(p,q, stroke_color = color)
self.add(line)
if (n + 1) % dev_y_step == 0 and n != 1:
j += dev_x_step
dev_stop = stop_points_left[j]
line = Line(dev_start,dev_stop,stroke_color = WHITE)
self.add(line)
dot = Dot(dev_stop, fill_color = WHITE)
self.add_foreground_mobject(dot)
dev_start = dev_stop
start_points = np.append(stop_points_left,[stop_points_right[-1]], axis = 0)
left_edge += level_height * DOWN
right_edge += level_height * DOWN
self.wait()