"""Animations that introduce mobjects to scene by growing them from points. .. manim:: Growing class Growing(Scene): def construct(self): square = Square() circle = Circle() triangle = Triangle() arrow = Arrow(LEFT, RIGHT) star = Star() VGroup(square, circle, triangle).set_x(0).arrange(buff=1.5).set_y(2) VGroup(arrow, star).move_to(DOWN).set_x(0).arrange(buff=1.5).set_y(-2) self.play(GrowFromPoint(square, ORIGIN)) self.play(GrowFromCenter(circle)) self.play(GrowFromEdge(triangle, DOWN)) self.play(GrowArrow(arrow)) self.play(SpinInFromNothing(star)) """ from __future__ import annotations __all__ = [ "GrowFromPoint", "GrowFromCenter", "GrowFromEdge", "GrowArrow", "SpinInFromNothing", ] from typing import TYPE_CHECKING, Any from ..animation.transform import Transform from ..constants import PI from ..utils.paths import spiral_path if TYPE_CHECKING: from manim.mobject.geometry.line import Arrow from manim.mobject.opengl.opengl_mobject import OpenGLMobject from manim.typing import Point3DLike, Vector3DLike from manim.utils.color import ParsableManimColor from ..mobject.mobject import Mobject class GrowFromPoint(Transform): """Introduce an :class:`~.Mobject` by growing it from a point. Parameters ---------- mobject The mobjects to be introduced. point The point from which the mobject grows. point_color Initial color of the mobject before growing to its full size. Leave empty to match mobject's color. Examples -------- .. manim :: GrowFromPointExample class GrowFromPointExample(Scene): def construct(self): dot = Dot(3 * UR, color=GREEN) squares = [Square() for _ in range(4)] VGroup(*squares).set_x(0).arrange(buff=1) self.add(dot) self.play(GrowFromPoint(squares[0], ORIGIN)) self.play(GrowFromPoint(squares[1], [-2, 2, 0])) self.play(GrowFromPoint(squares[2], [3, -2, 0], RED)) self.play(GrowFromPoint(squares[3], dot, dot.get_color())) """ def __init__( self, mobject: Mobject, point: Point3DLike, point_color: ParsableManimColor | None = None, **kwargs: Any, ): self.point = point self.point_color = point_color super().__init__(mobject, introducer=True, **kwargs) def create_target(self) -> Mobject | OpenGLMobject: return self.mobject def create_starting_mobject(self) -> Mobject | OpenGLMobject: start = super().create_starting_mobject() start.scale(0) start.move_to(self.point) if self.point_color: start.set_color(self.point_color) return start class GrowFromCenter(GrowFromPoint): """Introduce an :class:`~.Mobject` by growing it from its center. Parameters ---------- mobject The mobjects to be introduced. point_color Initial color of the mobject before growing to its full size. Leave empty to match mobject's color. Examples -------- .. manim :: GrowFromCenterExample class GrowFromCenterExample(Scene): def construct(self): squares = [Square() for _ in range(2)] VGroup(*squares).set_x(0).arrange(buff=2) self.play(GrowFromCenter(squares[0])) self.play(GrowFromCenter(squares[1], point_color=RED)) """ def __init__( self, mobject: Mobject, point_color: ParsableManimColor | None = None, **kwargs: Any, ): point = mobject.get_center() super().__init__(mobject, point, point_color=point_color, **kwargs) class GrowFromEdge(GrowFromPoint): """Introduce an :class:`~.Mobject` by growing it from one of its bounding box edges. Parameters ---------- mobject The mobjects to be introduced. edge The direction to seek bounding box edge of mobject. point_color Initial color of the mobject before growing to its full size. Leave empty to match mobject's color. Examples -------- .. manim :: GrowFromEdgeExample class GrowFromEdgeExample(Scene): def construct(self): squares = [Square() for _ in range(4)] VGroup(*squares).set_x(0).arrange(buff=1) self.play(GrowFromEdge(squares[0], DOWN)) self.play(GrowFromEdge(squares[1], RIGHT)) self.play(GrowFromEdge(squares[2], UR)) self.play(GrowFromEdge(squares[3], UP, point_color=RED)) """ def __init__( self, mobject: Mobject, edge: Vector3DLike, point_color: ParsableManimColor | None = None, **kwargs: Any, ): point = mobject.get_critical_point(edge) super().__init__(mobject, point, point_color=point_color, **kwargs) class GrowArrow(GrowFromPoint): """Introduce an :class:`~.Arrow` by growing it from its start toward its tip. Parameters ---------- arrow The arrow to be introduced. point_color Initial color of the arrow before growing to its full size. Leave empty to match arrow's color. Examples -------- .. manim :: GrowArrowExample class GrowArrowExample(Scene): def construct(self): arrows = [Arrow(2 * LEFT, 2 * RIGHT), Arrow(2 * DR, 2 * UL)] VGroup(*arrows).set_x(0).arrange(buff=2) self.play(GrowArrow(arrows[0])) self.play(GrowArrow(arrows[1], point_color=RED)) """ def __init__( self, arrow: Arrow, point_color: ParsableManimColor | None = None, **kwargs: Any ): point = arrow.get_start() super().__init__(arrow, point, point_color=point_color, **kwargs) def create_starting_mobject(self) -> Mobject | OpenGLMobject: start_arrow = self.mobject.copy() start_arrow.scale(0, scale_tips=True, about_point=self.point) if self.point_color: start_arrow.set_color(self.point_color) return start_arrow class SpinInFromNothing(GrowFromCenter): """Introduce an :class:`~.Mobject` spinning and growing it from its center. Parameters ---------- mobject The mobjects to be introduced. angle The amount of spinning before mobject reaches its full size. E.g. 2*PI means that the object will do one full spin before being fully introduced. point_color Initial color of the mobject before growing to its full size. Leave empty to match mobject's color. Examples -------- .. manim :: SpinInFromNothingExample class SpinInFromNothingExample(Scene): def construct(self): squares = [Square() for _ in range(3)] VGroup(*squares).set_x(0).arrange(buff=2) self.play(SpinInFromNothing(squares[0])) self.play(SpinInFromNothing(squares[1], angle=2 * PI)) self.play(SpinInFromNothing(squares[2], point_color=RED)) """ def __init__( self, mobject: Mobject, angle: float = PI / 2, point_color: ParsableManimColor | None = None, **kwargs: Any, ): self.angle = angle super().__init__( mobject, path_func=spiral_path(angle), point_color=point_color, **kwargs )