def zoom_in_on(self, number, zoom_factor, run_time=2.0): unit_length_to_spatial_width = self.number_line.unit_length_to_spatial_width * zoom_factor radius = SPACE_WIDTH / unit_length_to_spatial_width tick_frequency = 10**(np.floor(np.log10(radius))) left_tick = tick_frequency * (np.ceil( (number - radius) / tick_frequency)) new_number_line = NumberLine( numerical_radius=radius, unit_length_to_spatial_width=unit_length_to_spatial_width, tick_frequency=tick_frequency, leftmost_tick=left_tick, number_at_center=number) new_displayed_numbers = new_number_line.default_numbers_to_display() new_number_mobs = new_number_line.get_number_mobjects( *new_displayed_numbers) transforms = [] additional_mobjects = [] squished_new_line = new_number_line.copy() squished_new_line.scale(1.0 / zoom_factor) squished_new_line.shift(self.number_line.number_to_point(number)) squished_new_line.points[:, 1] = self.number_line.number_to_point(0)[1] transforms.append(Transform(squished_new_line, new_number_line)) for mob, num in zip(new_number_mobs, new_displayed_numbers): point = Point(self.number_line.number_to_point(num)) point.shift(new_number_line.get_vertical_number_offset()) transforms.append(Transform(point, mob)) for mob in self.mobjects: if mob == self.number_line: new_mob = mob.copy() new_mob.shift(-self.number_line.number_to_point(number)) new_mob.stretch(zoom_factor, 0) transforms.append(Transform(mob, new_mob)) continue mob_center = mob.get_center() number_under_center = self.number_line.point_to_number(mob_center) new_point = new_number_line.number_to_point(number_under_center) new_point += mob_center[1] * UP if mob in self.number_mobs: transforms.append(Transform(mob, Point(new_point))) else: transforms.append( ApplyMethod(mob.shift, new_point - mob_center)) additional_mobjects.append(mob) line_to_hide_pixelation = Line(self.number_line.get_left(), self.number_line.get_right(), color=self.number_line.get_color()) self.add(line_to_hide_pixelation) self.play(*transforms, run_time=run_time) self.clear() self.number_line = new_number_line self.displayed_numbers = new_displayed_numbers self.number_mobs = new_number_mobs self.add(self.number_line, *self.number_mobs) self.add(*additional_mobjects)