__all__ = ["BaseSlide"]
import platform
from abc import abstractmethod
from pathlib import Path
from typing import Any, List, MutableMapping, Optional, Sequence, Tuple, ValuesView
import numpy as np
from tqdm import tqdm
from ..config import PresentationConfig, PreSlideConfig, SlideConfig
from ..defaults import FFMPEG_BIN, FOLDER_PATH
from ..logger import logger
from ..utils import concatenate_video_files, merge_basenames, reverse_video_file
from . import MANIM
if MANIM:
from manim.mobject.mobject import Mobject
else:
Mobject = Any
LEFT: np.ndarray = np.array([-1.0, 0.0, 0.0])
class BaseSlide:
def __init__(
self, *args: Any, output_folder: Path = FOLDER_PATH, **kwargs: Any
) -> None:
super().__init__(*args, **kwargs)
self._output_folder: Path = output_folder
self._slides: List[PreSlideConfig] = []
self._pre_slide_config_kwargs: MutableMapping[str, Any] = {}
self._current_slide = 1
self._current_animation = 0
self._start_animation = 0
self._canvas: MutableMapping[str, Mobject] = {}
self._wait_time_between_slides = 0.0
@property
def _ffmpeg_bin(self) -> Path:
"""Return the path to the ffmpeg binaries."""
return FFMPEG_BIN
@property
@abstractmethod
def _frame_height(self) -> float:
"""Return the scene's frame height."""
...
@property
@abstractmethod
def _frame_width(self) -> float:
"""Return the scene's frame width."""
...
@property
@abstractmethod
def _background_color(self) -> str:
"""Return the scene's background color."""
...
@property
@abstractmethod
def _resolution(self) -> Tuple[int, int]:
"""Return the scene's resolution used during rendering."""
...
@property
@abstractmethod
def _partial_movie_files(self) -> List[Path]:
"""Return a list of partial movie files, a.k.a animations."""
...
@property
@abstractmethod
def _show_progress_bar(self) -> bool:
"""Return True if progress bar should be displayed."""
...
@property
@abstractmethod
def _leave_progress_bar(self) -> bool:
"""Return True if progress bar should be left after completed."""
...
@property
@abstractmethod
def _start_at_animation_number(self) -> Optional[int]:
"""If set, return the animation number at which rendering start."""
...
@property
def canvas(self) -> MutableMapping[str, Mobject]:
"""
Return the canvas associated to the current slide.
The canvas is a mapping between names and Mobjects,
for objects that are assumed to stay in multiple slides.
For example, a section title or a slide number.
Examples
--------
.. manim-slides:: CanvasExample
from manim import *
from manim_slides import Slide
class CanvasExample(Slide):
def update_canvas(self):
self.counter += 1
old_slide_number = self.canvas["slide_number"]
new_slide_number = Text(f"{self.counter}").move_to(old_slide_number)
self.play(Transform(old_slide_number, new_slide_number))
def construct(self):
title = Text("My Title").to_corner(UL)
self.counter = 1
slide_number = Text("1").to_corner(DL)
self.add_to_canvas(title=title, slide_number=slide_number)
self.play(FadeIn(title), FadeIn(slide_number))
self.next_slide()
circle = Circle(radius=2)
dot = Dot()
self.update_canvas()
self.play(Create(circle))
self.play(MoveAlongPath(dot, circle))
self.next_slide()
self.update_canvas()
square = Square()
self.wipe(self.mobjects_without_canvas, square)
self.next_slide()
self.update_canvas()
self.play(
Transform(
self.canvas["title"],
Text("New Title").to_corner(UL)
)
)
self.next_slide()
self.remove_from_canvas("title", "slide_number")
self.wipe(self.mobjects_without_canvas, [])
"""
return self._canvas
def add_to_canvas(self, **objects: Mobject) -> None:
"""
Add objects to the canvas, using key values as names.
:param objects: A mapping between names and Mobjects.
.. note::
This method does not actually do anything in terms of
animations. You must still call :code:`self.add` or
play some animation that introduces each Mobject for
it to appear. The same applies when removing objects.
"""
self._canvas.update(objects)
def remove_from_canvas(self, *names: str) -> None:
"""Remove objects from the canvas."""
for name in names:
self._canvas.pop(name)
@property
def canvas_mobjects(self) -> ValuesView[Mobject]:
"""Return Mobjects contained in the canvas."""
return self.canvas.values()
@property
def mobjects_without_canvas(self) -> Sequence[Mobject]:
"""
Return the list of objects contained in the scene, minus those present in
the canvas.
"""
return [
mobject for mobject in self.mobjects if mobject not in self.canvas_mobjects # type: ignore[attr-defined]
]
@property
def wait_time_between_slides(self) -> float:
r"""
Return the wait duration (in seconds) added between two slides.
By default, this value is set to 0.
Setting this value to something bigger than 0 will result in a
:code:`self.wait` animation called at the end of every slide.
.. note::
This is useful because animations are usually only terminated
when a new animation is played. You can observe the small difference
in the examples below: the circle is not fully complete in the first
slide of the first example, but well in the second example.
Examples
--------
.. manim-slides:: WithoutWaitExample
from manim import *
from manim_slides import Slide
class WithoutWaitExample(Slide):
def construct(self):
circle = Circle(radius=2)
arrow = Arrow().next_to(circle, RIGHT).scale(-1)
text = Text("Small\ngap").next_to(arrow, RIGHT)
self.play(Create(arrow), FadeIn(text))
self.play(Create(circle))
self.next_slide()
self.play(FadeOut(circle))
.. manim-slides:: WithWaitExample
from manim import *
from manim_slides import Slide
class WithWaitExample(Slide):
def construct(self):
self.wait_time_between_slides = 0.1 # A small value > 1 / FPS
circle = Circle(radius=2)
arrow = Arrow().next_to(circle, RIGHT).scale(-1)
text = Text("No more\ngap").next_to(arrow, RIGHT)
self.play(Create(arrow), FadeIn(text))
self.play(Create(circle))
self.next_slide()
self.play(FadeOut(circle))
"""
return self._wait_time_between_slides
@wait_time_between_slides.setter
def wait_time_between_slides(self, wait_time: float) -> None:
self._wait_time_between_slides = max(wait_time, 0.0)
def play(self, *args: Any, **kwargs: Any) -> None:
"""Overload `self.play` and increment animation count."""
super().play(*args, **kwargs) # type: ignore[misc]
self._current_animation += 1
def next_slide(self, *, loop: bool = False, **kwargs: Any) -> None:
"""
Create a new slide with previous animations, and setup options
for the next slide.
This usually means that the user will need to press some key before the
next slide is played. By default, this is the right arrow key.
:param args:
Positional arguments to be passed to
:meth:`Scene.next_section<manim.scene.scene.Scene.next_section>`,
or ignored if `manimlib` API is used.
:param loop:
If set, next slide will be looping.
:param kwargs:
Keyword arguments to be passed to
:meth:`Scene.next_section<manim.scene.scene.Scene.next_section>`,
or ignored if `manimlib` API is used.
.. note::
Calls to :func:`next_slide` at the very beginning or at the end are
not needed, since they are automatically added.
.. warning::
When rendered with RevealJS, loops cannot be in the first nor
the last slide.
.. seealso::
When using ``manim`` API, this method will also call
:meth:`Scene.next_section<manim.scene.scene.Scene.next_section>`.
Examples
--------
The following contains 3 slides:
#. the first with nothing on it;
#. the second with "Hello World!" fading in;
#. and the last with the text fading out;
.. manim-slides:: NextSlideExample
from manim import *
from manim_slides import Slide
class NextSlideExample(Slide):
def construct(self):
text = Text("Hello World!")
self.play(FadeIn(text))
self.next_slide()
self.play(FadeOut(text))
The following contains one slide that will loop endlessly.
.. manim-slides:: LoopExample
from manim import *
from manim_slides import Slide
class LoopExample(Slide):
def construct(self):
dot = Dot(color=BLUE, radius=1)
self.play(FadeIn(dot))
self.next_slide(loop=True)
self.play(Indicate(dot, scale_factor=2))
self.next_slide()
self.play(FadeOut(dot))
"""
if self._current_animation > self._start_animation:
if self.wait_time_between_slides > 0.0:
self.wait(self.wait_time_between_slides) # type: ignore[attr-defined]
self._slides.append(
PreSlideConfig(
start_animation=self._start_animation,
end_animation=self._current_animation,
**self._pre_slide_config_kwargs,
)
)
self._pre_slide_config_kwargs = dict(loop=loop)
self._current_slide += 1
self._start_animation = self._current_animation
def _add_last_slide(self) -> None:
"""Add a 'last' slide to the end of slides."""
if (
len(self._slides) > 0
and self._current_animation == self._slides[-1].end_animation
):
return
self._slides.append(
PreSlideConfig(
start_animation=self._start_animation,
end_animation=self._current_animation,
**self._pre_slide_config_kwargs,
)
)
def _save_slides(self, use_cache: bool = True) -> None:
"""
Save slides, optionally using cached files.
Note that cached files only work with Manim.
"""
self._add_last_slide()
files_folder = self._output_folder / "files"
scene_name = str(self)
scene_files_folder = files_folder / scene_name
scene_files_folder.mkdir(parents=True, exist_ok=True)
files: List[Path] = self._partial_movie_files
# We must filter slides that end before the animation offset
if offset := self._start_at_animation_number:
self._slides = [
slide for slide in self._slides if slide.end_animation > offset
]
for slide in self._slides:
slide.start_animation = max(0, slide.start_animation - offset)
slide.end_animation -= offset
slides: List[SlideConfig] = []
for pre_slide_config in tqdm(
self._slides,
desc=f"Concatenating animation files to '{scene_files_folder}' and generating reversed animations",
leave=self._leave_progress_bar,
ascii=True if platform.system() == "Windows" else None,
disable=not self._show_progress_bar,
):
slide_files = files[pre_slide_config.slides_slice]
file = merge_basenames(slide_files)
dst_file = scene_files_folder / file.name
rev_file = scene_files_folder / f"{file.stem}_reversed{file.suffix}"
# We only concat animations if it was not present
if not use_cache or not dst_file.exists():
concatenate_video_files(self._ffmpeg_bin, slide_files, dst_file)
# We only reverse video if it was not present
if not use_cache or not rev_file.exists():
reverse_video_file(self._ffmpeg_bin, dst_file, rev_file)
slides.append(
SlideConfig.from_pre_slide_config_and_files(
pre_slide_config, dst_file, rev_file
)
)
logger.info(
f"Generated {len(slides)} slides to '{scene_files_folder.absolute()}'"
)
slide_path = self._output_folder / f"{scene_name}.json"
PresentationConfig(
slides=slides,
resolution=self._resolution,
background_color=self._background_color,
).to_file(slide_path)
logger.info(
f"Slide '{scene_name}' configuration written in '{slide_path.absolute()}'"
)
def wipe(
self,
*args: Any,
direction: np.ndarray = LEFT,
**kwargs: Any,
) -> None:
"""
Play a wipe animation that will shift all the current objects outside of the
current scene's scope, and all the future objects inside.
:param args: Positional arguments passed to
:class:`Wipe<manim_slides.slide.animation.Wipe>`.
:param direction: The wipe direction, that will be scaled by the scene size.
:param kwargs: Keyword arguments passed to
:class:`Wipe<manim_slides.slide.animation.Wipe>`.
Examples
--------
.. manim-slides:: WipeExample
from manim import *
from manim_slides import Slide
class WipeExample(Slide):
def construct(self):
circle = Circle(radius=3, color=BLUE)
square = Square()
text = Text("This is a wipe example").next_to(square, DOWN)
beautiful = Text("Beautiful, no?")
self.play(FadeIn(circle))
self.next_slide()
self.wipe(circle, Group(square, text))
self.next_slide()
self.wipe(Group(square, text), beautiful, direction=UP)
self.next_slide()
self.wipe(beautiful, circle, direction=DOWN + RIGHT)
"""
from .animation import Wipe
shift_amount = np.asarray(direction) * np.array(
[self._frame_width, self._frame_height, 0.0]
)
kwargs.setdefault("shift", shift_amount)
animation = Wipe(
*args,
**kwargs,
)
self.play(animation)
def zoom(
self,
*args: Any,
**kwargs: Any,
) -> None:
"""
Play a zoom animation that will fade out all the current objects, and fade in
all the future objects. Objects are faded in a direction that goes towards the
camera.
:param args: Positional arguments passed to
:class:`Zoom<manim_slides.slide.animation.Zoom>`.
:param kwargs: Keyword arguments passed to
:class:`Zoom<manim_slides.slide.animation.Zoom>`.
Examples
--------
.. manim-slides:: ZoomExample
from manim import *
from manim_slides import Slide
class ZoomExample(Slide):
def construct(self):
circle = Circle(radius=3, color=BLUE)
square = Square()
self.play(FadeIn(circle))
self.next_slide()
self.zoom(circle, square)
self.next_slide()
self.zoom(square, circle, out=True, scale=10.0)
"""
from .animation import Zoom
animation = Zoom(*args, **kwargs)
self.play(animation)