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manim/active_projects/diffyq/part4/fourier_series_scenes.py

243 lines
7.1 KiB
Python

from manimlib.imports import *
from active_projects.ode.part2.fourier_series import FourierOfTrebleClef
class ComplexFourierSeriesExample(FourierOfTrebleClef):
CONFIG = {
"file_name": "EighthNote",
"run_time": 10,
"n_vectors": 200,
"n_cycles": 2,
"max_circle_stroke_width": 0.75,
"drawing_height": 5,
"center_point": DOWN,
"top_row_y": 3,
"top_row_label_y": 2,
"top_row_x_spacing": 1.75,
"top_row_copy_scale_factor": 0.9,
"start_drawn": False,
}
def construct(self):
self.add_vectors_circles_path()
self.add_top_row(self.vectors, self.circles)
self.write_title()
self.highlight_vectors_one_by_one()
self.change_shape()
def write_title(self):
title = TextMobject("Complex\\\\Fourier series")
title.scale(1.5)
title.to_edge(LEFT)
title.match_y(self.path)
self.wait(5)
self.play(FadeInFromDown(title))
self.wait(2)
self.title = title
def highlight_vectors_one_by_one(self):
# Don't know why these vectors can't get copied.
# That seems like a problem that will come up again.
labels = self.top_row[-1]
next_anims = []
for vector, circle, label in zip(self.vectors, self.circles, labels):
# v_color = vector.get_color()
c_color = circle.get_color()
c_stroke_width = circle.get_stroke_width()
rect = SurroundingRectangle(label, color=PINK)
self.play(
# vector.set_color, PINK,
circle.set_stroke, RED, 3,
FadeIn(rect),
*next_anims
)
self.wait()
next_anims = [
# vector.set_color, v_color,
circle.set_stroke, c_color, c_stroke_width,
FadeOut(rect),
]
self.play(*next_anims)
def change_shape(self):
# path_mob = TexMobject("\\pi")
path_mob = SVGMobject("Nail_And_Gear")
new_path = path_mob.family_members_with_points()[0]
new_path.set_height(4)
new_path.move_to(self.path, DOWN)
new_path.shift(0.5 * UP)
new_coefs = self.get_coefficients_of_path(new_path)
new_vectors = self.get_rotating_vectors(
coefficients=new_coefs
)
new_drawn_path = self.get_drawn_path(new_vectors)
self.vector_clock.set_value(0)
self.vector_clock.suspend_updating(0)
vectors = self.vectors
anims = []
for vect, new_vect in zip(vectors, new_vectors):
new_vect.update()
new_vect.clear_updaters()
line = Line(stroke_width=0)
line.put_start_and_end_on(*vect.get_start_and_end())
anims.append(ApplyMethod(
line.put_start_and_end_on,
*new_vect.get_start_and_end()
))
vect.freq = new_vect.freq
vect.phase = new_vect.phase
vect.coefficient = new_vect.coefficient
vect.line = line
vect.add_updater(
lambda v: v.put_start_and_end_on(
*v.line.get_start_and_end()
)
)
anims += [
FadeOut(self.drawn_path)
]
self.play(*anims, run_time=3)
self.vector_clock.resume_updating()
for vect in self.vectors:
vect.remove_updater(vect.updaters[-1])
self.add(new_drawn_path)
for n in range(self.n_cycles):
self.run_one_cycle()
#
def get_path(self):
path = super().get_path()
path.set_height(self.drawing_height)
path.to_edge(DOWN)
return path
def add_top_row(self, vectors, circles, max_freq=3):
self.top_row = self.get_top_row(
vectors, circles, max_freq
)
self.add(self.top_row)
def get_top_row(self, vectors, circles, max_freq=3):
vector_copies = VGroup()
circle_copies = VGroup()
for vector, circle in zip(vectors, circles):
if vector.freq > max_freq:
break
vcopy = vector.copy()
vcopy.clear_updaters()
ccopy = circle.copy()
ccopy.clear_updaters()
ccopy.original = circle
vcopy.original = vector
vcopy.center_point = np.array([
vector.freq * self.top_row_x_spacing,
self.top_row_y,
0
])
ccopy.center_point = vcopy.center_point
vcopy.add_updater(self.update_top_row_vector_copy)
ccopy.add_updater(self.update_top_row_circle_copy)
vector_copies.add(vcopy)
circle_copies.add(ccopy)
dots = VGroup(*[
TexMobject("\\dots").next_to(
circle_copies, direction,
MED_LARGE_BUFF,
)
for direction in [LEFT, RIGHT]
])
labels = self.get_top_row_labels(vector_copies)
return VGroup(
vector_copies,
circle_copies,
dots,
labels,
)
def update_top_row_vector_copy(self, vcopy):
vcopy.become(vcopy.original)
vcopy.scale(self.top_row_copy_scale_factor)
vcopy.shift(vcopy.center_point - vcopy.get_start())
return vcopy
def update_top_row_circle_copy(self, ccopy):
ccopy.become(ccopy.original)
ccopy.scale(self.top_row_copy_scale_factor)
ccopy.move_to(ccopy.center_point)
return ccopy
def get_top_row_labels(self, vector_copies):
labels = VGroup()
for vector_copy in vector_copies:
freq = vector_copy.freq
label = Integer(freq)
label.move_to(np.array([
freq * self.top_row_x_spacing,
self.top_row_label_y,
0
]))
labels.add(label)
return labels
class ComplexFourierSeriesExampleEnd(ExternallyAnimatedScene):
pass
class FourierSeriesExampleWithRectForZoom(ComplexFourierSeriesExample):
CONFIG = {
"n_vectors": 100,
"slow_factor": 0.01,
"rect_scale_factor": 0.15,
"parametric_function_step_size": 0.0001,
"start_drawn": True,
}
def construct(self):
self.add_vectors_circles_path()
self.circles.set_stroke(opacity=0.5)
rect = self.get_rect()
rect.set_height(self.rect_scale_factor * FRAME_HEIGHT)
rect.add_updater(lambda m: m.move_to(
center_of_mass([
v.get_end()
for v in self.vectors
])
))
self.add(rect)
self.run_one_cycle()
def get_rect(self):
return ScreenRectangle(
color=WHITE,
stroke_width=2,
)
class ZoomedInFourierSeriesExample(FourierSeriesExampleWithRectForZoom, MovingCameraScene):
CONFIG = {
"vector_config": {
"max_tip_length_to_length_ratio": 0.15,
"tip_length": 0.05,
}
}
def setup(self):
ComplexFourierSeriesExample.setup(self)
MovingCameraScene.setup(self)
def get_rect(self):
return self.camera_frame