3b1b-manim/manimlib/scene/scene.py

937 lines
31 KiB
Python

from __future__ import annotations
from collections import OrderedDict
import inspect
import os
import platform
import pyperclip
import random
import time
from IPython.terminal import pt_inputhooks
from IPython.terminal.embed import InteractiveShellEmbed
from IPython.core.getipython import get_ipython
import numpy as np
from tqdm import tqdm as ProgressDisplay
from manimlib.animation.animation import prepare_animation
from manimlib.camera.camera import Camera
from manimlib.config import get_module
from manimlib.constants import ARROW_SYMBOLS
from manimlib.constants import DEFAULT_WAIT_TIME
from manimlib.constants import COMMAND_MODIFIER
from manimlib.constants import SHIFT_MODIFIER
from manimlib.event_handler import EVENT_DISPATCHER
from manimlib.event_handler.event_type import EventType
from manimlib.logger import log
from manimlib.mobject.mobject import _AnimationBuilder
from manimlib.mobject.mobject import Group
from manimlib.mobject.mobject import Mobject
from manimlib.mobject.mobject import Point
from manimlib.mobject.types.vectorized_mobject import VGroup
from manimlib.mobject.types.vectorized_mobject import VMobject
from manimlib.scene.scene_file_writer import SceneFileWriter
from manimlib.utils.family_ops import extract_mobject_family_members
from manimlib.utils.family_ops import recursive_mobject_remove
from manimlib.utils.iterables import list_difference_update
from typing import TYPE_CHECKING
if TYPE_CHECKING:
from typing import Callable, Iterable
from PIL.Image import Image
from manimlib.animation.animation import Animation
PAN_3D_KEY = 'd'
FRAME_SHIFT_KEY = 'f'
ZOOM_KEY = 'z'
RESET_FRAME_KEY = 'r'
QUIT_KEY = 'q'
class Scene(object):
random_seed: int = 0
pan_sensitivity: float = 3.0
max_num_saved_states: int = 50
default_camera_config: dict = dict()
default_window_config: dict = dict()
default_file_writer_config: dict = dict()
def __init__(
self,
window_config: dict = dict(),
camera_config: dict = dict(),
file_writer_config: dict = dict(),
skip_animations: bool = False,
always_update_mobjects: bool = False,
start_at_animation_number: int | None = None,
end_at_animation_number: int | None = None,
leave_progress_bars: bool = False,
preview: bool = True,
presenter_mode: bool = False,
show_animation_progress: bool = False,
):
self.skip_animations = skip_animations
self.always_update_mobjects = always_update_mobjects
self.start_at_animation_number = start_at_animation_number
self.end_at_animation_number = end_at_animation_number
self.leave_progress_bars = leave_progress_bars
self.preview = preview
self.presenter_mode = presenter_mode
self.show_animation_progress = show_animation_progress
self.camera_config = {**self.default_camera_config, **camera_config}
self.window_config = {**self.default_window_config, **window_config}
self.file_writer_config = {**self.default_file_writer_config, **file_writer_config}
# Initialize window, if applicable
if self.preview:
from manimlib.window import Window
self.window = Window(scene=self, **self.window_config)
self.camera_config["ctx"] = self.window.ctx
self.camera_config["fps"] = 30 # Where's that 30 from?
else:
self.window = None
# Core state of the scene
self.camera: Camera = Camera(**self.camera_config)
self.file_writer = SceneFileWriter(self, **self.file_writer_config)
self.mobjects: list[Mobject] = [self.camera.frame]
self.id_to_mobject_map: dict[int, Mobject] = dict()
self.num_plays: int = 0
self.time: float = 0
self.skip_time: float = 0
self.original_skipping_status: bool = self.skip_animations
self.checkpoint_states: dict[str, list[tuple[Mobject, Mobject]]] = dict()
self.undo_stack = []
self.redo_stack = []
if self.start_at_animation_number is not None:
self.skip_animations = True
if self.file_writer.has_progress_display():
self.show_animation_progress = False
# Items associated with interaction
self.mouse_point = Point()
self.mouse_drag_point = Point()
self.hold_on_wait = self.presenter_mode
self.quit_interaction = False
# Much nicer to work with deterministic scenes
if self.random_seed is not None:
random.seed(self.random_seed)
np.random.seed(self.random_seed)
def __str__(self) -> str:
return self.__class__.__name__
def run(self) -> None:
self.virtual_animation_start_time: float = 0
self.real_animation_start_time: float = time.time()
self.file_writer.begin()
self.setup()
try:
self.construct()
self.interact()
except EndScene:
pass
except KeyboardInterrupt:
# Get rid keyboard interupt symbols
print("", end="\r")
self.file_writer.ended_with_interrupt = True
self.tear_down()
def setup(self) -> None:
"""
This is meant to be implement by any scenes which
are comonly subclassed, and have some common setup
involved before the construct method is called.
"""
pass
def construct(self) -> None:
# Where all the animation happens
# To be implemented in subclasses
pass
def tear_down(self) -> None:
self.stop_skipping()
self.file_writer.finish()
if self.window:
self.window.destroy()
self.window = None
def interact(self) -> None:
"""
If there is a window, enter a loop
which updates the frame while under
the hood calling the pyglet event loop
"""
if self.window is None:
return
log.info(
"\nTips: Using the keys `d`, `f`, or `z` " +
"you can interact with the scene. " +
"Press `command + q` or `esc` to quit"
)
self.skip_animations = False
self.refresh_static_mobjects()
while not self.is_window_closing():
self.update_frame(1 / self.camera.fps)
def embed(
self,
close_scene_on_exit: bool = True,
show_animation_progress: bool = True,
) -> None:
if not self.preview:
return # Embed is only relevant with a preview
self.stop_skipping()
self.update_frame()
self.save_state()
self.show_animation_progress = show_animation_progress
# Create embedded IPython terminal to be configured
shell = InteractiveShellEmbed.instance()
# Use the locals namespace of the caller
caller_frame = inspect.currentframe().f_back
local_ns = dict(caller_frame.f_locals)
# Add a few custom shortcuts
local_ns.update(
play=self.play,
wait=self.wait,
add=self.add,
remove=self.remove,
clear=self.clear,
save_state=self.save_state,
undo=self.undo,
redo=self.redo,
i2g=self.i2g,
i2m=self.i2m,
checkpoint_paste=self.checkpoint_paste,
)
# Enables gui interactions during the embed
def inputhook(context):
while not context.input_is_ready():
if not self.is_window_closing():
self.update_frame(dt=0)
if self.is_window_closing():
shell.ask_exit()
pt_inputhooks.register("manim", inputhook)
shell.enable_gui("manim")
# This is hacky, but there's an issue with ipython which is that
# when you define lambda's or list comprehensions during a shell session,
# they are not aware of local variables in the surrounding scope. Because
# That comes up a fair bit during scene construction, to get around this,
# we (admittedly sketchily) update the global namespace to match the local
# namespace, since this is just a shell session anyway.
shell.events.register(
"pre_run_cell",
lambda: shell.user_global_ns.update(shell.user_ns)
)
# Operation to run after each ipython command
def post_cell_func():
self.refresh_static_mobjects()
if not self.is_window_closing():
self.update_frame(dt=0, ignore_skipping=True)
self.save_state()
shell.events.register("post_run_cell", post_cell_func)
# Launch shell
shell(
local_ns=local_ns,
# Pretend like we're embeding in the caller function, not here
stack_depth=2,
# Specify that the present module is the caller's, not here
module=get_module(caller_frame.f_globals["__file__"])
)
# End scene when exiting an embed
if close_scene_on_exit:
raise EndScene()
# Only these methods should touch the camera
def get_image(self) -> Image:
return self.camera.get_image()
def show(self) -> None:
self.update_frame(ignore_skipping=True)
self.get_image().show()
def update_frame(self, dt: float = 0, ignore_skipping: bool = False) -> None:
self.increment_time(dt)
self.update_mobjects(dt)
if self.skip_animations and not ignore_skipping:
return
if self.is_window_closing():
raise EndScene()
if self.window:
self.window.clear()
self.camera.clear()
self.camera.capture(*self.mobjects)
if self.window:
self.window.swap_buffers()
vt = self.time - self.virtual_animation_start_time
rt = time.time() - self.real_animation_start_time
if rt < vt:
self.update_frame(0)
def emit_frame(self) -> None:
if not self.skip_animations:
self.file_writer.write_frame(self.camera)
# Related to updating
def update_mobjects(self, dt: float) -> None:
for mobject in self.mobjects:
mobject.update(dt)
def should_update_mobjects(self) -> bool:
return self.always_update_mobjects or any([
len(mob.get_family_updaters()) > 0
for mob in self.mobjects
])
def has_time_based_updaters(self) -> bool:
return any([
sm.has_time_based_updater()
for mob in self.mobjects()
for sm in mob.get_family()
])
# Related to time
def get_time(self) -> float:
return self.time
def increment_time(self, dt: float) -> None:
self.time += dt
# Related to internal mobject organization
def get_top_level_mobjects(self) -> list[Mobject]:
# Return only those which are not in the family
# of another mobject from the scene
mobjects = self.get_mobjects()
families = [m.get_family() for m in mobjects]
def is_top_level(mobject):
num_families = sum([
(mobject in family)
for family in families
])
return num_families == 1
return list(filter(is_top_level, mobjects))
def get_mobject_family_members(self) -> list[Mobject]:
return extract_mobject_family_members(self.mobjects)
def add(self, *new_mobjects: Mobject):
"""
Mobjects will be displayed, from background to
foreground in the order with which they are added.
"""
self.remove(*new_mobjects)
self.mobjects += new_mobjects
self.id_to_mobject_map.update({
id(sm): sm
for m in new_mobjects
for sm in m.get_family()
})
return self
def add_mobjects_among(self, values: Iterable):
"""
This is meant mostly for quick prototyping,
e.g. to add all mobjects defined up to a point,
call self.add_mobjects_among(locals().values())
"""
self.add(*filter(
lambda m: isinstance(m, Mobject),
values
))
return self
def replace(self, mobject: Mobject, *replacements: Mobject):
if mobject in self.mobjects:
index = self.mobjects.index(mobject)
self.mobjects = [
*self.mobjects[:index],
*replacements,
*self.mobjects[index + 1:]
]
return self
def remove(self, *mobjects_to_remove: Mobject):
"""
Removes anything in mobjects from scenes mobject list, but in the event that one
of the items to be removed is a member of the family of an item in mobject_list,
the other family members are added back into the list.
For example, if the scene includes Group(m1, m2, m3), and we call scene.remove(m1),
the desired behavior is for the scene to then include m2 and m3 (ungrouped).
"""
to_remove = set(extract_mobject_family_members(mobjects_to_remove))
new_mobjects, _ = recursive_mobject_remove(self.mobjects, to_remove)
self.mobjects = new_mobjects
def bring_to_front(self, *mobjects: Mobject):
self.add(*mobjects)
return self
def bring_to_back(self, *mobjects: Mobject):
self.remove(*mobjects)
self.mobjects = list(mobjects) + self.mobjects
return self
def clear(self):
self.mobjects = []
return self
def get_mobjects(self) -> list[Mobject]:
return list(self.mobjects)
def get_mobject_copies(self) -> list[Mobject]:
return [m.copy() for m in self.mobjects]
def point_to_mobject(
self,
point: np.ndarray,
search_set: Iterable[Mobject] | None = None,
buff: float = 0
) -> Mobject | None:
"""
E.g. if clicking on the scene, this returns the top layer mobject
under a given point
"""
if search_set is None:
search_set = self.mobjects
for mobject in reversed(search_set):
if mobject.is_point_touching(point, buff=buff):
return mobject
return None
def get_group(self, *mobjects):
if all(isinstance(m, VMobject) for m in mobjects):
return VGroup(*mobjects)
else:
return Group(*mobjects)
def id_to_mobject(self, id_value):
return self.id_to_mobject_map[id_value]
def ids_to_group(self, *id_values):
return self.get_group(*filter(
lambda x: x is not None,
map(self.id_to_mobject, id_values)
))
def i2g(self, *id_values):
return self.ids_to_group(*id_values)
def i2m(self, id_value):
return self.id_to_mobject(id_value)
# Related to skipping
def update_skipping_status(self) -> None:
if self.start_at_animation_number is not None:
if self.num_plays == self.start_at_animation_number:
self.skip_time = self.time
if not self.original_skipping_status:
self.stop_skipping()
if self.end_at_animation_number is not None:
if self.num_plays >= self.end_at_animation_number:
raise EndScene()
def stop_skipping(self) -> None:
self.virtual_animation_start_time = self.time
self.skip_animations = False
# Methods associated with running animations
def get_time_progression(
self,
run_time: float,
n_iterations: int | None = None,
desc: str = "",
override_skip_animations: bool = False
) -> list[float] | np.ndarray | ProgressDisplay:
if self.skip_animations and not override_skip_animations:
return [run_time]
times = np.arange(0, run_time, 1 / self.camera.fps)
self.file_writer.set_progress_display_description(sub_desc=desc)
if self.show_animation_progress:
return ProgressDisplay(
times,
total=n_iterations,
leave=self.leave_progress_bars,
ascii=True if platform.system() == 'Windows' else None,
desc=desc,
)
else:
return times
def get_run_time(self, animations: Iterable[Animation]) -> float:
return np.max([animation.get_run_time() for animation in animations])
def get_animation_time_progression(
self,
animations: Iterable[Animation]
) -> list[float] | np.ndarray | ProgressDisplay:
animations = list(animations)
run_time = self.get_run_time(animations)
description = f"{self.num_plays} {animations[0]}"
if len(animations) > 1:
description += ", etc."
time_progression = self.get_time_progression(run_time, desc=description)
return time_progression
def get_wait_time_progression(
self,
duration: float,
stop_condition: Callable[[], bool] | None = None
) -> list[float] | np.ndarray | ProgressDisplay:
kw = {"desc": f"{self.num_plays} Waiting"}
if stop_condition is not None:
kw["n_iterations"] = -1 # So it doesn't show % progress
kw["override_skip_animations"] = True
return self.get_time_progression(duration, **kw)
def pre_play(self):
if self.presenter_mode and self.num_plays == 0:
self.hold_loop()
self.update_skipping_status()
if not self.skip_animations:
self.file_writer.begin_animation()
if self.window:
self.real_animation_start_time = time.time()
self.virtual_animation_start_time = self.time
self.refresh_static_mobjects()
def post_play(self):
if not self.skip_animations:
self.file_writer.end_animation()
if self.skip_animations and self.window is not None:
# Show some quick frames along the way
self.update_frame(dt=0, ignore_skipping=True)
self.num_plays += 1
def refresh_static_mobjects(self) -> None:
self.camera.refresh_static_mobjects()
def begin_animations(self, animations: Iterable[Animation]) -> None:
for animation in animations:
animation.begin()
# Anything animated that's not already in the
# scene gets added to the scene. Note, for
# animated mobjects that are in the family of
# those on screen, this can result in a restructuring
# of the scene.mobjects list, which is usually desired.
if animation.mobject not in self.mobjects:
self.add(animation.mobject)
def progress_through_animations(self, animations: Iterable[Animation]) -> None:
last_t = 0
for t in self.get_animation_time_progression(animations):
dt = t - last_t
last_t = t
for animation in animations:
animation.update_mobjects(dt)
alpha = t / animation.run_time
animation.interpolate(alpha)
self.update_frame(dt)
self.emit_frame()
def finish_animations(self, animations: Iterable[Animation]) -> None:
for animation in animations:
animation.finish()
animation.clean_up_from_scene(self)
if self.skip_animations:
self.update_mobjects(self.get_run_time(animations))
else:
self.update_mobjects(0)
def play(
self,
*proto_animations: Animation | _AnimationBuilder,
run_time: float | None = None,
rate_func: Callable[[float], float] | None = None,
lag_ratio: float | None = None,
) -> None:
if len(proto_animations) == 0:
log.warning("Called Scene.play with no animations")
return
animations = list(map(prepare_animation, proto_animations))
for anim in animations:
anim.update_rate_info(run_time, rate_func, lag_ratio)
self.pre_play()
self.begin_animations(animations)
self.progress_through_animations(animations)
self.finish_animations(animations)
self.post_play()
def wait(
self,
duration: float = DEFAULT_WAIT_TIME,
stop_condition: Callable[[], bool] = None,
note: str = None,
ignore_presenter_mode: bool = False
):
self.pre_play()
self.update_mobjects(dt=0) # Any problems with this?
if self.presenter_mode and not self.skip_animations and not ignore_presenter_mode:
if note:
log.info(note)
self.hold_loop()
else:
time_progression = self.get_wait_time_progression(duration, stop_condition)
last_t = 0
for t in time_progression:
dt = t - last_t
last_t = t
self.update_frame(dt)
self.emit_frame()
if stop_condition is not None and stop_condition():
break
self.refresh_static_mobjects()
self.post_play()
def hold_loop(self):
while self.hold_on_wait:
self.update_frame(dt=1 / self.camera.fps)
self.hold_on_wait = True
def wait_until(
self,
stop_condition: Callable[[], bool],
max_time: float = 60
):
self.wait(max_time, stop_condition=stop_condition)
def force_skipping(self):
self.original_skipping_status = self.skip_animations
self.skip_animations = True
return self
def revert_to_original_skipping_status(self):
if hasattr(self, "original_skipping_status"):
self.skip_animations = self.original_skipping_status
return self
def add_sound(
self,
sound_file: str,
time_offset: float = 0,
gain: float | None = None,
gain_to_background: float | None = None
):
if self.skip_animations:
return
time = self.get_time() + time_offset
self.file_writer.add_sound(sound_file, time, gain, gain_to_background)
# Helpers for interactive development
def get_state(self) -> SceneState:
return SceneState(self)
def restore_state(self, scene_state: SceneState):
scene_state.restore_scene(self)
def save_state(self) -> None:
if not self.preview:
return
state = self.get_state()
if self.undo_stack and state.mobjects_match(self.undo_stack[-1]):
return
self.redo_stack = []
self.undo_stack.append(state)
if len(self.undo_stack) > self.max_num_saved_states:
self.undo_stack.pop(0)
def undo(self):
if self.undo_stack:
self.redo_stack.append(self.get_state())
self.restore_state(self.undo_stack.pop())
self.refresh_static_mobjects()
def redo(self):
if self.redo_stack:
self.undo_stack.append(self.get_state())
self.restore_state(self.redo_stack.pop())
self.refresh_static_mobjects()
def checkpoint_paste(self, skip: bool = False):
"""
Used during interactive development to run (or re-run)
a block of scene code.
If the copied selection starts with a comment, this will
revert to the state of the scene the first time this function
was called on a block of code starting with that comment.
"""
shell = get_ipython()
if shell is None:
raise Exception(
"Scene.checkpoint_paste cannot be called outside of " +
"an ipython shell"
)
pasted = pyperclip.paste()
line0 = pasted.lstrip().split("\n")[0]
if line0.startswith("#"):
if line0 not in self.checkpoint_states:
self.checkpoint(line0)
else:
self.revert_to_checkpoint(line0)
prev_skipping = self.skip_animations
self.skip_animations = skip
shell.run_cell(pasted)
self.skip_animations = prev_skipping
def checkpoint(self, key: str):
self.checkpoint_states[key] = self.get_state()
def revert_to_checkpoint(self, key: str):
if key not in self.checkpoint_states:
log.error(f"No checkpoint at {key}")
return
all_keys = list(self.checkpoint_states.keys())
index = all_keys.index(key)
for later_key in all_keys[index + 1:]:
self.checkpoint_states.pop(later_key)
self.restore_state(self.checkpoint_states[key])
def clear_checkpoints(self):
self.checkpoint_states = dict()
def save_mobject_to_file(self, mobject: Mobject, file_path: str | None = None) -> None:
if file_path is None:
file_path = self.file_writer.get_saved_mobject_path(mobject)
if file_path is None:
return
mobject.save_to_file(file_path)
def load_mobject(self, file_name):
if os.path.exists(file_name):
path = file_name
else:
directory = self.file_writer.get_saved_mobject_directory()
path = os.path.join(directory, file_name)
return Mobject.load(path)
def is_window_closing(self):
return self.window and (self.window.is_closing or self.quit_interaction)
# Event handling
def on_mouse_motion(
self,
point: np.ndarray,
d_point: np.ndarray
) -> None:
self.mouse_point.move_to(point)
event_data = {"point": point, "d_point": d_point}
propagate_event = EVENT_DISPATCHER.dispatch(EventType.MouseMotionEvent, **event_data)
if propagate_event is not None and propagate_event is False:
return
frame = self.camera.frame
# Handle perspective changes
if self.window.is_key_pressed(ord(PAN_3D_KEY)):
frame.increment_theta(-self.pan_sensitivity * d_point[0])
frame.increment_phi(self.pan_sensitivity * d_point[1])
# Handle frame movements
elif self.window.is_key_pressed(ord(FRAME_SHIFT_KEY)):
shift = -d_point
shift[0] *= frame.get_width() / 2
shift[1] *= frame.get_height() / 2
transform = frame.get_inverse_camera_rotation_matrix()
shift = np.dot(np.transpose(transform), shift)
frame.shift(shift)
def on_mouse_drag(
self,
point: np.ndarray,
d_point: np.ndarray,
buttons: int,
modifiers: int
) -> None:
self.mouse_drag_point.move_to(point)
event_data = {"point": point, "d_point": d_point, "buttons": buttons, "modifiers": modifiers}
propagate_event = EVENT_DISPATCHER.dispatch(EventType.MouseDragEvent, **event_data)
if propagate_event is not None and propagate_event is False:
return
def on_mouse_press(
self,
point: np.ndarray,
button: int,
mods: int
) -> None:
self.mouse_drag_point.move_to(point)
event_data = {"point": point, "button": button, "mods": mods}
propagate_event = EVENT_DISPATCHER.dispatch(EventType.MousePressEvent, **event_data)
if propagate_event is not None and propagate_event is False:
return
def on_mouse_release(
self,
point: np.ndarray,
button: int,
mods: int
) -> None:
event_data = {"point": point, "button": button, "mods": mods}
propagate_event = EVENT_DISPATCHER.dispatch(EventType.MouseReleaseEvent, **event_data)
if propagate_event is not None and propagate_event is False:
return
def on_mouse_scroll(
self,
point: np.ndarray,
offset: np.ndarray
) -> None:
event_data = {"point": point, "offset": offset}
propagate_event = EVENT_DISPATCHER.dispatch(EventType.MouseScrollEvent, **event_data)
if propagate_event is not None and propagate_event is False:
return
frame = self.camera.frame
if self.window.is_key_pressed(ord(ZOOM_KEY)):
factor = 1 + np.arctan(10 * offset[1])
frame.scale(1 / factor, about_point=point)
else:
transform = frame.get_inverse_camera_rotation_matrix()
shift = np.dot(np.transpose(transform), offset)
frame.shift(-20.0 * shift)
def on_key_release(
self,
symbol: int,
modifiers: int
) -> None:
event_data = {"symbol": symbol, "modifiers": modifiers}
propagate_event = EVENT_DISPATCHER.dispatch(EventType.KeyReleaseEvent, **event_data)
if propagate_event is not None and propagate_event is False:
return
def on_key_press(
self,
symbol: int,
modifiers: int
) -> None:
try:
char = chr(symbol)
except OverflowError:
log.warning("The value of the pressed key is too large.")
return
event_data = {"symbol": symbol, "modifiers": modifiers}
propagate_event = EVENT_DISPATCHER.dispatch(EventType.KeyPressEvent, **event_data)
if propagate_event is not None and propagate_event is False:
return
if char == RESET_FRAME_KEY:
self.play(self.camera.frame.animate.to_default_state())
elif char == "z" and modifiers == COMMAND_MODIFIER:
self.undo()
elif char == "z" and modifiers == COMMAND_MODIFIER | SHIFT_MODIFIER:
self.redo()
# command + q
elif char == QUIT_KEY and modifiers == COMMAND_MODIFIER:
self.quit_interaction = True
# Space or right arrow
elif char == " " or symbol == ARROW_SYMBOLS[2]:
self.hold_on_wait = False
def on_resize(self, width: int, height: int) -> None:
self.camera.reset_pixel_shape(width, height)
def on_show(self) -> None:
pass
def on_hide(self) -> None:
pass
def on_close(self) -> None:
pass
class SceneState():
def __init__(self, scene: Scene, ignore: list[Mobject] | None = None):
self.time = scene.time
self.num_plays = scene.num_plays
self.mobjects_to_copies = OrderedDict.fromkeys(scene.mobjects)
if ignore:
for mob in ignore:
self.mobjects_to_copies.pop(mob, None)
last_m2c = scene.undo_stack[-1].mobjects_to_copies if scene.undo_stack else dict()
for mob in self.mobjects_to_copies:
# If it hasn't changed since the last state, just point to the
# same copy as before
if mob in last_m2c and last_m2c[mob].looks_identical(mob):
self.mobjects_to_copies[mob] = last_m2c[mob]
else:
self.mobjects_to_copies[mob] = mob.copy()
def __eq__(self, state: SceneState):
return all((
self.time == state.time,
self.num_plays == state.num_plays,
self.mobjects_to_copies == state.mobjects_to_copies
))
def mobjects_match(self, state: SceneState):
return self.mobjects_to_copies == state.mobjects_to_copies
def n_changes(self, state: SceneState):
m2c = state.mobjects_to_copies
return sum(
1 - int(mob in m2c and mob.looks_identical(m2c[mob]))
for mob in self.mobjects_to_copies
)
def restore_scene(self, scene: Scene):
scene.time = self.time
scene.num_plays = self.num_plays
scene.mobjects = [
mob.become(mob_copy)
for mob, mob_copy in self.mobjects_to_copies.items()
]
class EndScene(Exception):
pass