wslでmanim その9

概要

wslでmanimやってみた。
練習問題やってみた。

練習問題

sin,cosをわかりやすく、説明せよ。

成果物

サンプルコード

from manim import *

class SineCosine_Curve(Scene):
	def construct(self):
		self.show_axis()
		self.show_circle()
		self.move_dot_and_draw_curve()
		self.wait()
	def show_axis(self):
		x_start = np.array([-6, 2, 0])
		x_end = np.array([3, 2, 0])
		y_start = np.array([-4, -3, 0])
		y_end = np.array([-4, 3.5, 0])
		x_axis = Line(x_start, x_end)
		y_axis = Line(y_start, y_end)
		self.add(x_axis, y_axis)
		self.add_xy_labels()
		self.orgin_point = np.array([-4, 2, 0])
		self.curve_start = np.array([-3, 2, 0])
	def add_xy_labels(self):
		x_labels = [Text("\pi"), Text("2 \pi"), Text("3 \pi"), Text("4 \pi"),]
		y_labels = [Text("\pi"), Text("2 \pi"), Text("3 \pi"), Text("4 \pi"),]
		for i in range(len(x_labels)):
			x_labels[i].scale(0.6)
			x_labels[i].next_to(np.array([-2 + i, 2, 0]), DOWN)
			self.add(x_labels[i])
		for i in range(len(y_labels)):
			y_labels[i].scale(0.6)
			y_labels[i].rotate(-PI/2)
			y_labels[i].next_to(np.array([-4, 1 - i, 0]), LEFT)
			self.add(y_labels[i])
	def show_circle(self):
		circle = Circle(radius = 1)
		circle.move_to(self.orgin_point)
		self.add(circle)
		self.circle = circle
	def move_dot_and_draw_curve(self):
		orbit = self.circle
		orgin_point = self.orgin_point
		dot = Dot(radius = 0.08, color = YELLOW)
		dot.move_to(orbit.point_from_proportion(0))
		self.t_offset = 0
		rate = 0.25
		def go_around_circle(mob, dt):
			self.t_offset += (dt * rate)
			mob.move_to(orbit.point_from_proportion(self.t_offset % 1))
		def get_line_to_circle():
			return Line(orgin_point, dot.get_center(), color=BLUE)
		def get_line_to_sine():
			x = self.curve_start[0] + self.t_offset * 2
			y = dot.get_center()[1]
			return Line(dot.get_center(), np.array([x, y, 0]), color = YELLOW_A, stroke_width = 2)
		self.sine_curve = VGroup()
		self.sine_curve.add(Line(self.curve_start,self.curve_start))
		def get_sine_curve():
			last_line = self.sine_curve[-1]
			x = self.curve_start[0] + self.t_offset * 2
			y = dot.get_center()[1]
			new_line = Line(last_line.get_end(),np.array([x, y, 0]), color = YELLOW_D)
			self.sine_curve.add(new_line)
			return self.sine_curve
		def get_line_to_cosine():
			x = dot.get_center()[0]
			y = self.curve_start[1] - self.t_offset * 2
			return Line(dot.get_center(), np.array([x, y, 0]), color = YELLOW_A, stroke_width = 2)
		self.cosine_curve = VGroup()
		self.cosine_curve.add(Line(self.curve_start, self.curve_start))
		def get_cosine_curve():
			last_line = self.cosine_curve[-1]
			x = dot.get_center()[0]
			y = self.curve_start[1] - self.t_offset * 2
			new_line = Line(last_line.get_end(), np.array([x, y, 0]), color = YELLOW_D)
			self.cosine_curve.add(new_line)
			return self.cosine_curve
		dot.add_updater(go_around_circle)
		origin_to_circle_line = always_redraw(get_line_to_circle)
		dot_to_sine_line = always_redraw(get_line_to_sine)
		sine_curve_line = always_redraw(get_sine_curve)
		dot_to_cosine_line = always_redraw(get_line_to_cosine)
		cosine_curve_line = always_redraw(get_cosine_curve)
		self.add(dot, orbit)
		self.add(origin_to_circle_line, dot_to_sine_line, sine_curve_line, dot_to_cosine_line, cosine_curve_line, )
		self.wait(8.5)
		dot.remove_updater(go_around_circle)

以上。