"""Mobjects used to mark and annotate other mobjects."""
from __future__ import annotations
__all__ = ["SurroundingRectangle", "BackgroundRectangle", "Cross", "Underline"]
from typing import Any
from typing_extensions import Self
from manim import config, logger
from manim.constants import *
from manim.mobject.geometry.line import Line
from manim.mobject.geometry.polygram import RoundedRectangle
from manim.mobject.mobject import Mobject
from manim.mobject.types.vectorized_mobject import VGroup
from manim.utils.color import BLACK, RED, YELLOW, ManimColor, ParsableManimColor
[docs]class SurroundingRectangle(RoundedRectangle):
r"""A rectangle surrounding a :class:`~.Mobject`
Examples
--------
.. manim:: SurroundingRectExample
:save_last_frame:
class SurroundingRectExample(Scene):
def construct(self):
title = Title("A Quote from Newton")
quote = Text(
"If I have seen further than others, \n"
"it is by standing upon the shoulders of giants.",
color=BLUE,
).scale(0.75)
box = SurroundingRectangle(quote, color=YELLOW, buff=MED_LARGE_BUFF)
t2 = Tex(r"Hello World").scale(1.5)
box2 = SurroundingRectangle(t2, corner_radius=0.2)
mobjects = VGroup(VGroup(box, quote), VGroup(t2, box2)).arrange(DOWN)
self.add(title, mobjects)
"""
def __init__(
self,
mobject: Mobject,
color: ParsableManimColor = YELLOW,
buff: float = SMALL_BUFF,
corner_radius: float = 0.0,
**kwargs,
) -> None:
super().__init__(
color=color,
width=mobject.width + 2 * buff,
height=mobject.height + 2 * buff,
corner_radius=corner_radius,
**kwargs,
)
self.buff = buff
self.move_to(mobject)
[docs]class BackgroundRectangle(SurroundingRectangle):
"""A background rectangle. Its default color is the background color
of the scene.
Examples
--------
.. manim:: ExampleBackgroundRectangle
:save_last_frame:
class ExampleBackgroundRectangle(Scene):
def construct(self):
circle = Circle().shift(LEFT)
circle.set_stroke(color=GREEN, width=20)
triangle = Triangle().shift(2 * RIGHT)
triangle.set_fill(PINK, opacity=0.5)
backgroundRectangle1 = BackgroundRectangle(circle, color=WHITE, fill_opacity=0.15)
backgroundRectangle2 = BackgroundRectangle(triangle, color=WHITE, fill_opacity=0.15)
self.add(backgroundRectangle1)
self.add(backgroundRectangle2)
self.add(circle)
self.add(triangle)
self.play(Rotate(backgroundRectangle1, PI / 4))
self.play(Rotate(backgroundRectangle2, PI / 2))
"""
def __init__(
self,
mobject: Mobject,
color: ParsableManimColor | None = None,
stroke_width: float = 0,
stroke_opacity: float = 0,
fill_opacity: float = 0.75,
buff: float = 0,
**kwargs,
):
if color is None:
color = config.background_color
super().__init__(
mobject,
color=color,
stroke_width=stroke_width,
stroke_opacity=stroke_opacity,
fill_opacity=fill_opacity,
buff=buff,
**kwargs,
)
self.original_fill_opacity: float = self.fill_opacity
[docs] def pointwise_become_partial(self, mobject: Mobject, a: Any, b: float) -> Self:
self.set_fill(opacity=b * self.original_fill_opacity)
return self
def set_style(self, fill_opacity: float, **kwargs) -> Self:
# Unchangeable style, except for fill_opacity
# All other style arguments are ignored
super().set_style(
stroke_color=BLACK,
stroke_width=0,
fill_color=BLACK,
fill_opacity=fill_opacity,
)
if len(kwargs) > 0:
logger.info(
"Argument %s is ignored in BackgroundRectangle.set_style.",
kwargs,
)
return self
[docs] def get_fill_color(self) -> ManimColor:
return self.color
[docs]class Cross(VGroup):
"""Creates a cross.
Parameters
----------
mobject
The mobject linked to this instance. It fits the mobject when specified. Defaults to None.
stroke_color
Specifies the color of the cross lines. Defaults to RED.
stroke_width
Specifies the width of the cross lines. Defaults to 6.
scale_factor
Scales the cross to the provided units. Defaults to 1.
Examples
--------
.. manim:: ExampleCross
:save_last_frame:
class ExampleCross(Scene):
def construct(self):
cross = Cross()
self.add(cross)
"""
def __init__(
self,
mobject: Mobject | None = None,
stroke_color: ParsableManimColor = RED,
stroke_width: float = 6.0,
scale_factor: float = 1.0,
**kwargs,
) -> None:
super().__init__(
Line(UP + LEFT, DOWN + RIGHT), Line(UP + RIGHT, DOWN + LEFT), **kwargs
)
if mobject is not None:
self.replace(mobject, stretch=True)
self.scale(scale_factor)
self.set_stroke(color=stroke_color, width=stroke_width)
[docs]class Underline(Line):
"""Creates an underline.
Examples
--------
.. manim:: UnderLine
:save_last_frame:
class UnderLine(Scene):
def construct(self):
man = Tex("Manim") # Full Word
ul = Underline(man) # Underlining the word
self.add(man, ul)
"""
def __init__(self, mobject: Mobject, buff: float = SMALL_BUFF, **kwargs) -> None:
super().__init__(LEFT, RIGHT, buff=buff, **kwargs)
self.match_width(mobject)
self.next_to(mobject, DOWN, buff=self.buff)