[43]Transform(3)

ApplyMethod

        arrow = Arrow().to_edge(LEFT)

        self.add(arrow)
        self.play(ApplyMethod(arrow.to_edge, RIGHT))
        self.wait()

 

 

---

ApplyPointwiseFunction Class

    def apply_pointwise_function(self):
        circle = Circle(radius=0.5)
        circle.save_state()

        self.add(circle)
        self.wait()

        self.play(
            ApplyPointwiseFunction(
                lambda p: 10 * p / get_norm(p),
                circle
            )
        )
        self.play(Restore(circle))

        circle.set_fill(color=RED, opacity=0.5)
        self.play(
            ApplyPointwiseFunction(
                lambda p: 10 * p / get_norm(p),
                circle
            )
        )

        self.wait(2)

 

 

 

---

ApplyFunction Class

    def apply_function(self):
        circle = Circle(fill_opacity=1, color=RED).shift(DOWN)
        circle.save_state()

        self.add(circle)
        self.wait()

        self.play(
            ApplyFunction(
                lambda m : m.fade(1).shift(5*DOWN),
                circle,
                run_time=6,
            )
        )

        self.wait(2)

 

 

---

Homotopy Class

    def homotopy(self):
        def homotopy_x(x, y, z, t):
            alpha = (0.7*x + FRAME_Y_RADIUS)/(FRAME_HEIGHT)
            beta = squish_rate_func(smooth, alpha-0.15, alpha+0.15)(t)
            return (x - 0.3*np.sin(np.pi*beta), y, z)

        def homotopy_y(x, y, z, t):
            alpha = (0.7*x + FRAME_X_RADIUS)/(FRAME_WIDTH)
            beta = squish_rate_func(smooth, alpha-0.15, alpha+0.15)(t)
            return (x, y - 0.3*np.sin(np.pi*beta), z)

        text = TextMobject("Homotopy Animation")
        circle = Circle()
        square = Square()
        objs = VGroup(text, circle, square).arrange(RIGHT, buff=1)

        self.add(objs)
        self.wait()

        for i in range(0, 2):
            self.play(Homotopy(homotopy_x, objs))

        for i in range(0, 2):
            self.play(Homotopy(homotopy_y, objs))
        self.wait()

 

---

PhaseFlow Class

    def phase_flow(self):
        name_text = Text("PhaseFlow", stroke_width=0, size=0.4, color=YELLOW)
        name_text.to_corner(UL)

        plane = NumberPlane(color=BLUE_E)
        square = Circle(color=YELLOW)
        plane.add(square)

        self.add(plane, name_text)
        self.wait()

        def func(t):
            return t * 0.1 * RIGHT

        self.play(PhaseFlow(
            func, plane,
            run_time=5,
            virtual_time=8,
        ))