예제 #1
0
    def construct(self):
        words, s = TextMobject(["Pseudo-Hilbert Curve", "s"]).split()
        pre_words = TextMobject("Order 1")
        pre_words.next_to(words, LEFT, buff = 0.5)
        s.next_to(words, RIGHT, buff = 0.05, aligned_edge = DOWN)
        cluster = Mobject(pre_words, words, s)
        cluster.center()
        cluster.scale(0.7)
        cluster.to_edge(UP, buff = 0.3)
        cluster.highlight(GREEN)
        grid1 = Grid(1, 1)
        grid2 = Grid(2, 2)
        curve = HilbertCurve(order = 1)

        self.add(words, s)
        self.dither()
        self.play(Transform(
            s, pre_words, 
            path_func = path_along_arc(-np.pi/3)
        ))
        self.dither()
        self.play(ShowCreation(grid1))
        self.dither()
        self.play(ShowCreation(grid2))
        self.dither()
        kwargs = {
            "run_time" : 5,
            "rate_func" : None
        }
        self.play(ShowCreation(curve, **kwargs))
        self.dither()
예제 #2
0
    def show_pendulum(self, arc_angle = np.pi, arc_color = GREEN):
        words = TextMobject(": Instantaneous center of rotation")
        words.next_to(self.c_label)
        line = Line(self.p_point, self.c_point)
        line_angle = line.get_angle()+np.pi
        line_length = line.get_length()
        line.add(self.p_dot.copy())
        line.get_center = lambda : self.c_point
        tangent_line = Line(3*LEFT, 3*RIGHT)
        tangent_line.rotate(line_angle-np.pi/2)
        tangent_line.shift(self.p_point)
        tangent_line.highlight(arc_color)
        right_angle_symbol = Mobject(
            Line(UP, UP+RIGHT),
            Line(UP+RIGHT, RIGHT)
        )
        right_angle_symbol.scale(0.3)
        right_angle_symbol.rotate(tangent_line.get_angle()+np.pi)
        right_angle_symbol.shift(self.p_point)

        self.play(ShowCreation(line))
        self.play(ShimmerIn(words))
        self.dither()
        pairs = [    
            (line_angle, arc_angle/2),
            (line_angle+arc_angle/2, -arc_angle),
            (line_angle-arc_angle/2, arc_angle/2),
        ]
        arcs = []
        for start, angle in pairs:
            arc = Arc(
                angle = angle,
                radius = line_length,
                start_angle = start,
                color = GREEN
            )
            arc.shift(self.c_point)
            self.play(
                ShowCreation(arc),
                ApplyMethod(
                    line.rotate_in_place, 
                    angle,
                    path_func = path_along_arc(angle)
                ),
                run_time = 2
            )
            arcs.append(arc)
        self.dither()
        self.play(Transform(arcs[1], tangent_line))
        self.add(tangent_line)
        self.play(ShowCreation(right_angle_symbol))
        self.dither()

        self.tangent_line = tangent_line
        self.right_angle_symbol = right_angle_symbol
        self.pc_line = line
        self.remove(words, *arcs)
예제 #3
0
    def show_pendulum(self, arc_angle = np.pi, arc_color = GREEN):
        words = TextMobject(": Instantaneous center of rotation")
        words.next_to(self.c_label)
        line = Line(self.p_point, self.c_point)
        line_angle = line.get_angle()+np.pi
        line_length = line.get_length()
        line.add(self.p_dot.copy())
        line.get_center = lambda : self.c_point
        tangent_line = Line(3*LEFT, 3*RIGHT)
        tangent_line.rotate(line_angle-np.pi/2)
        tangent_line.shift(self.p_point)
        tangent_line.highlight(arc_color)
        right_angle_symbol = Mobject(
            Line(UP, UP+RIGHT),
            Line(UP+RIGHT, RIGHT)
        )
        right_angle_symbol.scale(0.3)
        right_angle_symbol.rotate(tangent_line.get_angle()+np.pi)
        right_angle_symbol.shift(self.p_point)

        self.play(ShowCreation(line))
        self.play(ShimmerIn(words))
        self.wait()
        pairs = [    
            (line_angle, arc_angle/2),
            (line_angle+arc_angle/2, -arc_angle),
            (line_angle-arc_angle/2, arc_angle/2),
        ]
        arcs = []
        for start, angle in pairs:
            arc = Arc(
                angle = angle,
                radius = line_length,
                start_angle = start,
                color = GREEN
            )
            arc.shift(self.c_point)
            self.play(
                ShowCreation(arc),
                ApplyMethod(
                    line.rotate_in_place, 
                    angle,
                    path_func = path_along_arc(angle)
                ),
                run_time = 2
            )
            arcs.append(arc)
        self.wait()
        self.play(Transform(arcs[1], tangent_line))
        self.add(tangent_line)
        self.play(ShowCreation(right_angle_symbol))
        self.wait()

        self.tangent_line = tangent_line
        self.right_angle_symbol = right_angle_symbol
        self.pc_line = line
        self.remove(words, *arcs)