Merge pull request #2262 from 3b1b/video-work

Refactor scene creation

manimlib/__main__.py

@@ -3,7 +3,7 @@ from manimlib import __version__
 import manimlib.config
 import manimlib.logger
 import manimlib.utils.init_config
-from manimlib.reload_manager import reload_manager
+from manimlib.reload_manager import ReloadManager
 
 
 def main():
@@ -22,7 +22,7 @@ def main():
         manimlib.utils.init_config.init_customization()
         return
 
-    reload_manager.args = args
+    reload_manager = ReloadManager(args)
     reload_manager.run()
 
 

manimlib/config.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 import argparse
-from argparse import Namespace
 import colour
 import importlib
 import inspect
@@ -13,21 +12,15 @@ import yaml
 from functools import lru_cache
 
 from manimlib.logger import log
-from manimlib.module_loader import ModuleLoader
 from manimlib.utils.dict_ops import merge_dicts_recursively
 from manimlib.utils.init_config import init_customization
 
 from typing import TYPE_CHECKING
 if TYPE_CHECKING:
-    Module = importlib.util.types.ModuleType
+    from argparse import Namespace
     from typing import Optional
 
 
-# This has to be here instead of in constants.py
-# due to its use in creating the camera configuration
-FRAME_HEIGHT: float = 8.0
-
-
 def parse_cli():
     try:
         parser = argparse.ArgumentParser()
@@ -144,12 +137,8 @@ def parse_cli():
         )
         parser.add_argument(
             "-e", "--embed",
-            nargs="?",
-            const="",
             help="Creates a new file where the line `self.embed` is inserted " + \
-                 "into the Scenes construct method. " + \
+                 "at the corresponding line number"
-                 "If a string is passed in, the line will be inserted below the " + \
-                 "last line of code including that string."
         )
         parser.add_argument(
             "-r", "--resolution",
@@ -210,93 +199,6 @@ def get_manim_dir():
     return os.path.abspath(os.path.join(manimlib_dir, ".."))
 
 
-def get_indent(line: str):
-    return len(line) - len(line.lstrip())
-
-
-def get_module_with_inserted_embed_line(
-    file_name: str, scene_name: str, line_marker: str, is_during_reload
-):
-    """
-    This is hacky, but convenient. When user includes the argument "-e", it will try
-    to recreate a file that inserts the line `self.embed()` into the end of the scene's
-    construct method. If there is an argument passed in, it will insert the line after
-    the last line in the sourcefile which includes that string.
-    """
-    with open(file_name, 'r') as fp:
-        lines = fp.readlines()
-
-    try:
-        scene_line_number = next(
-            i for i, line in enumerate(lines)
-            if line.startswith(f"class {scene_name}")
-        )
-    except StopIteration:
-        log.error(f"No scene {scene_name}")
-        return
-
-    prev_line_num = -1
-    n_spaces = None
-    if len(line_marker) == 0:
-        # Find the end of the construct method
-        in_construct = False
-        for index in range(scene_line_number, len(lines) - 1):
-            line = lines[index]
-            if line.lstrip().startswith("def construct"):
-                in_construct = True
-                n_spaces = get_indent(line) + 4
-            elif in_construct:
-                if len(line.strip()) > 0 and get_indent(line) < (n_spaces or 0):
-                    prev_line_num = index - 1
-                    break
-        if prev_line_num < 0:
-            prev_line_num = len(lines) - 1
-    elif line_marker.isdigit():
-        # Treat the argument as a line number
-        prev_line_num = int(line_marker) - 1
-    elif len(line_marker) > 0:
-        # Treat the argument as a string
-        try:
-            prev_line_num = next(
-                i
-                for i in range(scene_line_number, len(lines) - 1)
-                if line_marker in lines[i]
-            )
-        except StopIteration:
-            log.error(f"No lines matching {line_marker}")
-            sys.exit(2)
-
-    # Insert the embed line, rewrite file, then write it back when done
-    if n_spaces is None:
-        n_spaces = get_indent(lines[prev_line_num])
-    inserted_line = " " * n_spaces + "self.embed()\n"
-    new_lines = list(lines)
-    new_lines.insert(prev_line_num + 1, inserted_line)
-    new_file = file_name.replace(".py", "_insert_embed.py")
-
-    with open(new_file, 'w') as fp:
-        fp.writelines(new_lines)
-
-    module = ModuleLoader.get_module(new_file, is_during_reload)
-    # This is to pretend the module imported from the edited lines
-    # of code actually comes from the original file.
-    module.__file__ = file_name
-
-    os.remove(new_file)
-
-    return module
-
-
-def get_scene_module(args: Namespace) -> Module:
-    if args.embed is None:
-        return ModuleLoader.get_module(args.file)
-    else:
-        is_reload = args.is_reload if hasattr(args, "is_reload") else False
-        return get_module_with_inserted_embed_line(
-            args.file, args.scene_names[0], args.embed, is_reload
-        )
-
-
 def load_yaml(file_path: str):
     try:
         with open(file_path, "r") as file:
@@ -343,8 +245,8 @@ def get_animations_numbers(args: Namespace) -> tuple[int | None, int | None]:
         return int(stan), None
 
 
-def get_output_directory(args: Namespace, custom_config: dict) -> str:
+def get_output_directory(args: Namespace, global_config: dict) -> str:
-    dir_config = custom_config["directories"]
+    dir_config = global_config["directories"]
     output_directory = args.video_dir or dir_config["output"]
     if dir_config["mirror_module_path"] and args.file:
         to_cut = dir_config["removed_mirror_prefix"]
@@ -356,7 +258,7 @@ def get_output_directory(args: Namespace, custom_config: dict) -> str:
     return output_directory
 
 
-def get_file_writer_config(args: Namespace, custom_config: dict) -> dict:
+def get_file_writer_config(args: Namespace, global_config: dict) -> dict:
     result = {
         "write_to_movie": not args.skip_animations and args.write_file,
         "save_last_frame": args.skip_animations and args.write_file,
@@ -364,13 +266,13 @@ def get_file_writer_config(args: Namespace, custom_config: dict) -> dict:
         # If -t is passed in (for transparent), this will be RGBA
         "png_mode": "RGBA" if args.transparent else "RGB",
         "movie_file_extension": get_file_ext(args),
-        "output_directory": get_output_directory(args, custom_config),
+        "output_directory": get_output_directory(args, global_config),
         "file_name": args.file_name,
         "input_file_path": args.file or "",
         "open_file_upon_completion": args.open,
         "show_file_location_upon_completion": args.finder,
         "quiet": args.quiet,
-        **custom_config["file_writer_config"],
+        **global_config["file_writer_config"],
     }
 
     if args.vcodec:
@@ -387,32 +289,11 @@ def get_file_writer_config(args: Namespace, custom_config: dict) -> dict:
     return result
 
 
-def get_window_config(args: Namespace, custom_config: dict, camera_config: dict) -> dict:
+def get_resolution(args: Optional[Namespace] = None, global_config: Optional[dict] = None):
-    # Default to making window half the screen size
+    args = args or parse_cli()
-    # but make it full screen if -f is passed in
+    global_config = global_config or get_global_config()
-    try:
-        monitors = screeninfo.get_monitors()
-    except screeninfo.ScreenInfoError:
-        # Default fallback
-        monitors = [screeninfo.Monitor(width=1920, height=1080)]
-    mon_index = custom_config["window_monitor"]
-    monitor = monitors[min(mon_index, len(monitors) - 1)]
-    aspect_ratio = camera_config["pixel_width"] / camera_config["pixel_height"]
-    window_width = monitor.width
-    if not (args.full_screen or custom_config["full_screen"]):
-        window_width //= 2
-    window_height = int(window_width / aspect_ratio)
-    return dict(size=(window_width, window_height))
 
-
+    camera_resolutions = global_config["camera_resolutions"]
-def get_camera_config(args: Optional[Namespace] = None, custom_config: Optional[dict] = None) -> dict:
-    if args is None:
-        args = parse_cli()
-    if custom_config is None:
-        custom_config = get_global_config()
-
-    camera_config = dict()
-    camera_resolutions = custom_config["camera_resolutions"]
     if args.resolution:
         resolution = args.resolution
     elif args.low_quality:
@@ -426,33 +307,53 @@ def get_camera_config(args: Optional[Namespace] = None, custom_config: Optional[
     else:
         resolution = camera_resolutions[camera_resolutions["default_resolution"]]
 
-    if args.fps:
-        fps = int(args.fps)
-    else:
-        fps = custom_config["fps"]
-
     width_str, height_str = resolution.split("x")
-    width = int(width_str)
+    return int(width_str), int(height_str)
-    height = int(height_str)
 
-    camera_config.update({
+
+def get_window_config(args: Namespace, global_config: dict) -> dict:
+    # Default to making window half the screen size
+    # but make it full screen if -f is passed in
+    try:
+        monitors = screeninfo.get_monitors()
+    except screeninfo.ScreenInfoError:
+        # Default fallback
+        monitors = [screeninfo.Monitor(width=1920, height=1080)]
+    mon_index = global_config["window_monitor"]
+    monitor = monitors[min(mon_index, len(monitors) - 1)]
+
+    width, height = get_resolution(args, global_config)
+
+    aspect_ratio = width / height
+    window_width = monitor.width
+    if not (args.full_screen or global_config["full_screen"]):
+        window_width //= 2
+    window_height = int(window_width / aspect_ratio)
+    return dict(size=(window_width, window_height))
+
+
+def get_camera_config(args: Optional[Namespace] = None, global_config: Optional[dict] = None) -> dict:
+    args = args or parse_cli()
+    global_config = global_config or get_global_config()
+
+    width, height = get_resolution(args, global_config)
+    fps = int(args.fps or global_config["fps"])
+
+    camera_config = {
         "pixel_width": width,
         "pixel_height": height,
-        "frame_config": {
-            "frame_shape": ((width / height) * FRAME_HEIGHT, FRAME_HEIGHT),
-        },
         "fps": fps,
-    })
+    }
 
     try:
-        bg_color = args.color or custom_config["style"]["background_color"]
+        bg_color = args.color or global_config["style"]["background_color"]
         camera_config["background_color"] = colour.Color(bg_color)
     except ValueError as err:
         log.error("Please use a valid color")
         log.error(err)
         sys.exit(2)
 
-    # If rendering a transparent image/move, make sure the
+    # If rendering a transparent image/movie, make sure the
     # scene has a background opacity of 0
     if args.transparent:
         camera_config["background_opacity"] = 0
@@ -466,17 +367,15 @@ def get_scene_config(args: Namespace) -> dict:
     """
     global_config = get_global_config()
     camera_config = get_camera_config(args, global_config)
-    window_config = get_window_config(args, global_config, camera_config)
+    file_writer_config = get_file_writer_config(args, global_config)
     start, end = get_animations_numbers(args)
 
     return {
-        "file_writer_config": get_file_writer_config(args, global_config),
+        "file_writer_config": file_writer_config,
         "camera_config": camera_config,
-        "window_config": window_config,
         "skip_animations": args.skip_animations,
         "start_at_animation_number": start,
         "end_at_animation_number": end,
-        "preview": not args.write_file,
         "presenter_mode": args.presenter_mode,
         "leave_progress_bars": args.leave_progress_bars,
         "show_animation_progress": args.show_animation_progress,
@@ -486,10 +385,15 @@ def get_scene_config(args: Namespace) -> dict:
 
 
 def get_run_config(args: Namespace):
+    window_config = get_window_config(args, get_global_config())
     return {
-        "module": get_scene_module(args),
+        "file_name": args.file,
+        "embed_line": int(args.embed) if args.embed is not None else None,
+        "is_reload": False,
         "prerun": args.prerun,
         "scene_names": args.scene_names,
         "quiet": args.quiet or args.write_all,
         "write_all": args.write_all,
+        "window_config": window_config,
+        "show_in_window": not args.write_file
     }

manimlib/constants.py

@@ -1,8 +1,7 @@
 from __future__ import annotations
 import numpy as np
 
-from manimlib.config import get_camera_config
+from manimlib.config import get_resolution
-from manimlib.config import FRAME_HEIGHT
 
 from typing import TYPE_CHECKING
 if TYPE_CHECKING:
@@ -13,18 +12,19 @@ if TYPE_CHECKING:
 # TODO, it feels a bit unprincipled to have some global constants
 # depend on the output of this function, and for all that configuration
 # code to be run merely upon importing from this file.
-CAMERA_CONFIG = get_camera_config()
+DEFAULT_RESOLUTION: tuple[int, int] = get_resolution()
+DEFAULT_PIXEL_WIDTH = DEFAULT_RESOLUTION[0]
+DEFAULT_PIXEL_HEIGHT = DEFAULT_RESOLUTION[1]
+DEFAULT_FPS: int = 30
 
 # Sizes relevant to default camera frame
-ASPECT_RATIO: float = CAMERA_CONFIG['pixel_width'] / CAMERA_CONFIG['pixel_height']
+ASPECT_RATIO: float = DEFAULT_PIXEL_WIDTH / DEFAULT_PIXEL_HEIGHT
+FRAME_HEIGHT: float = 8.0
 FRAME_WIDTH: float = FRAME_HEIGHT * ASPECT_RATIO
 FRAME_SHAPE: tuple[float, float] = (FRAME_WIDTH, FRAME_HEIGHT)
 FRAME_Y_RADIUS: float = FRAME_HEIGHT / 2
 FRAME_X_RADIUS: float = FRAME_WIDTH / 2
 
-DEFAULT_PIXEL_HEIGHT: int = CAMERA_CONFIG['pixel_height']
-DEFAULT_PIXEL_WIDTH: int = CAMERA_CONFIG['pixel_width']
-DEFAULT_FPS: int = 30
 
 SMALL_BUFF: float = 0.1
 MED_SMALL_BUFF: float = 0.25

manimlib/default_config.yml

@@ -58,3 +58,4 @@ camera_resolutions:
 fps: 30
 embed_exception_mode: "Verbose"
 embed_error_sound: False
+ignore_manimlib_modules_on_reload: True

manimlib/extract_scene.py

@@ -1,12 +1,21 @@
+from __future__ import annotations
+
 import copy
 import inspect
 import sys
 
+from manimlib.module_loader import ModuleLoader
+
 from manimlib.config import get_global_config
 from manimlib.logger import log
 from manimlib.scene.interactive_scene import InteractiveScene
 from manimlib.scene.scene import Scene
 
+from typing import TYPE_CHECKING
+if TYPE_CHECKING:
+    Module = importlib.util.types.ModuleType
+    from typing import Optional
+
 
 class BlankScene(InteractiveScene):
     def construct(self):
@@ -115,10 +124,60 @@ def get_scene_classes_from_module(module):
         ]
 
 
+def get_indent(code_lines: list[str], line_number: int) -> str:
+    """
+    Find the indent associated with a given line of python code,
+    as a string of spaces
+    """
+    # Find most recent non-empty line
+    try:
+        line = next(filter(lambda line: line.strip(), code_lines[line_number - 1::-1]))
+    except StopIteration:
+        return ""
+
+    # Either return its leading spaces, or add for if it ends with colon
+    n_spaces = len(line) - len(line.lstrip())
+    if line.endswith(":"):
+        n_spaces += 4
+    return n_spaces * " "
+
+
+def insert_embed_line_to_module(module: Module, line_number: int):
+    """
+    This is hacky, but convenient. When user includes the argument "-e", it will try
+    to recreate a file that inserts the line `self.embed()` into the end of the scene's
+    construct method. If there is an argument passed in, it will insert the line after
+    the last line in the sourcefile which includes that string.
+    """
+    lines = inspect.getsource(module).splitlines()
+
+    # Add the relevant embed line to the code
+    indent = get_indent(lines, line_number)
+    lines.insert(line_number, indent + "self.embed()")
+    new_code = "\n".join(lines)
+
+    # Execute the code, which presumably redefines the user's
+    # scene to include this embed line, within the relevant module.
+    code_object = compile(new_code, module.__name__, 'exec')
+    exec(code_object, module.__dict__)
+
+
+def get_scene_module(file_name: Optional[str], embed_line: Optional[int], is_reload: bool = False) -> Module:
+    module = ModuleLoader.get_module(file_name, is_reload)
+    if embed_line:
+        insert_embed_line_to_module(module, embed_line)
+    return module
+
+
 def main(scene_config, run_config):
-    if run_config["module"] is None:
+    module = get_scene_module(
+        run_config["file_name"],
+        run_config["embed_line"],
+        run_config["is_reload"]
+    )
+    if module is None:
         # If no module was passed in, just play the blank scene
         return [BlankScene(**scene_config)]
 
-    all_scene_classes = get_scene_classes_from_module(run_config["module"])
+    all_scene_classes = get_scene_classes_from_module(module)
     return get_scenes_to_render(all_scene_classes, scene_config, run_config)

manimlib/logger.py

@@ -11,4 +11,4 @@ logging.basicConfig(
 )
 
 log = logging.getLogger("manimgl")
-log.setLevel("DEBUG")
+log.setLevel("WARNING")

manimlib/mobject/mobject.py

@@ -715,21 +715,6 @@ class Mobject(object):
         self.become(self.saved_state)
         return self
 
-    def save_to_file(self, file_path: str) -> Self:
-        with open(file_path, "wb") as fp:
-            fp.write(self.serialize())
-        log.info(f"Saved mobject to {file_path}")
-        return self
-
-    @staticmethod
-    def load(file_path) -> Mobject:
-        if not os.path.exists(file_path):
-            log.error(f"No file found at {file_path}")
-            sys.exit(2)
-        with open(file_path, "rb") as fp:
-            mobject = pickle.load(fp)
-        return mobject
-
     def become(self, mobject: Mobject, match_updaters=False) -> Self:
         """
         Edit all data and submobjects to be idential

manimlib/module_loader.py

@@ -6,12 +6,11 @@ import os
 import sys
 import sysconfig
 
+from manimlib.config import get_global_config
 from manimlib.logger import log
 
 Module = importlib.util.types.ModuleType
 
-IGNORE_MANIMLIB_MODULES = True
-
 
 class ModuleLoader:
     """
@@ -76,10 +75,7 @@ class ModuleLoader:
         builtins.__import__ = tracked_import
 
         try:
-            # Remove the "_insert_embed" suffix from the module name
             module_name = module.__name__
-            if module.__name__.endswith("_insert_embed"):
-                module_name = module_name[:-13]
             log.debug('Reloading module "%s"', module_name)
 
             spec.loader.exec_module(module)
@@ -146,7 +142,8 @@ class ModuleLoader:
 
         Only user-defined modules are reloaded, see `is_user_defined_module()`.
         """
-        if IGNORE_MANIMLIB_MODULES and module.__name__.startswith("manimlib"):
+        ignore_manimlib_modules = get_global_config()["ignore_manimlib_modules_on_reload"]
+        if ignore_manimlib_modules and module.__name__.startswith("manimlib"):
             return
 
         if not hasattr(module, "__dict__"):

manimlib/reload_manager.py

@@ -1,7 +1,20 @@
+from __future__ import annotations
+
 from typing import Any
 from IPython.terminal.embed import KillEmbedded
 
 
+import manimlib.config
+import manimlib.extract_scene
+
+from manimlib.window import Window
+
+
+from typing import TYPE_CHECKING
+if TYPE_CHECKING:
+    from argparse import Namespace
+
+
 class ReloadManager:
     """
     Manages the loading and running of scenes and is called directly from the
@@ -12,20 +25,17 @@ class ReloadManager:
     command in the IPython shell.
     """
 
-    args: Any = None
-    scenes: list[Any] = []
     window = None
-
-    # The line number to load the scene from when reloading
-    start_at_line = None
-
     is_reload = False
 
+    def __init__(self, cli_args: Namespace):
+        self.args = cli_args
+
     def set_new_start_at_line(self, start_at_line):
         """
         Sets/Updates the line number to load the scene from when reloading.
         """
-        self.start_at_line = start_at_line
+        self.args.embed = str(start_at_line)
 
     def run(self):
         """
@@ -34,61 +44,43 @@ class ReloadManager:
         while True:
             try:
                 # blocking call since a scene will init an IPython shell()
-                self.retrieve_scenes_and_run(self.start_at_line)
+                self.retrieve_scenes_and_run()
                 return
             except KillEmbedded:
                 # Requested via the `exit_raise` IPython runline magic
                 # by means of our scene.reload() command
-                for scene in self.scenes:
+                self.note_reload()
-                    scene.tear_down()
-
-                self.scenes = []
-                self.is_reload = True
-
             except KeyboardInterrupt:
                 break
 
-    def retrieve_scenes_and_run(self, overwrite_start_at_line: int | None = None):
+    def note_reload(self):
+        self.is_reload = True
+        print(" ".join([
+            "Reloading interactive session for",
+            f"\033[96m{self.args.scene_names[0]}\033[0m",
+            f"at line \033[96m{self.args.embed}\033[0m"
+        ]))
+
+    def retrieve_scenes_and_run(self):
         """
         Creates a new configuration based on the CLI args and runs the scenes.
         """
-        import manimlib.config
-        import manimlib.extract_scene
-
-        # Args
-        if self.args is None:
-            raise RuntimeError("Fatal error: No args were passed to the ReloadManager")
-        if overwrite_start_at_line is not None:
-            self.args.embed = str(overwrite_start_at_line)
-
         # Args to Config
-        self.args.is_reload = self.is_reload
         scene_config = manimlib.config.get_scene_config(self.args)
-        if self.window:
+        scene_config.update(reload_manager=self)
-            scene_config["existing_window"] = self.window  # see scene initialization
 
         run_config = manimlib.config.get_run_config(self.args)
+        run_config.update(is_reload=self.is_reload)
+
+        # Create or reuse window
+        if run_config["show_in_window"] and not self.window:
+            self.window = Window(**run_config["window_config"])
+        scene_config.update(window=self.window)
 
         # Scenes
-        self.scenes = manimlib.extract_scene.main(scene_config, run_config)
+        scenes = manimlib.extract_scene.main(scene_config, run_config)
-        if len(self.scenes) == 0:
+        if len(scenes) == 0:
             print("No scenes found to run")
-            return
 
-        # Find first available window
+        for scene in scenes:
-        for scene in self.scenes:
-            if scene.window is not None:
-                self.window = scene.window
-                break
-
-        for scene in self.scenes:
-            if self.args.embed:
-                print(" ".join([
-                    "Loading interactive session for",
-                    f"\033[96m{self.args.scene_names[0]}\033[0m",
-                    f"in \033[96m{self.args.file}\033[0m",
-                    f"at line \033[96m{self.args.embed}\033[0m"
-                ]))
             scene.run()
-
-reload_manager = ReloadManager()

manimlib/scene/interactive_scene.py

@@ -460,12 +460,6 @@ class InteractiveScene(Scene):
             nudge *= 10
         self.selection.shift(nudge * vect)
 
-    def save_selection_to_file(self):
-        if len(self.selection) == 1:
-            self.save_mobject_to_file(self.selection[0])
-        else:
-            self.save_mobject_to_file(self.selection)
-
     # Key actions
     def on_key_press(self, symbol: int, modifiers: int) -> None:
         super().on_key_press(symbol, modifiers)
@@ -503,8 +497,6 @@ class InteractiveScene(Scene):
             self.ungroup_selection()
         elif char == "t" and (modifiers & (PygletWindowKeys.MOD_COMMAND | PygletWindowKeys.MOD_CTRL)):
             self.toggle_selection_mode()
-        elif char == "s" and (modifiers & (PygletWindowKeys.MOD_COMMAND | PygletWindowKeys.MOD_CTRL)):
-            self.save_selection_to_file()
         elif char == "d" and (modifiers & PygletWindowKeys.MOD_SHIFT):
             self.copy_frame_positioning()
         elif char == "c" and (modifiers & PygletWindowKeys.MOD_SHIFT):

manimlib/scene/scene.py

@@ -1,41 +1,33 @@
 from __future__ import annotations
 
 from collections import OrderedDict
-import inspect
 import os
 import platform
-import pyperclip
 import random
 import time
-import re
 from functools import wraps
 
-from IPython.terminal import pt_inputhooks
-from IPython.terminal.embed import InteractiveShellEmbed
 from pyglet.window import key as PygletWindowKeys
 
 import numpy as np
 from tqdm.auto import tqdm as ProgressDisplay
 
 from manimlib.animation.animation import prepare_animation
-from manimlib.animation.fading import VFadeInThenOut
 from manimlib.camera.camera import Camera
 from manimlib.camera.camera_frame import CameraFrame
-from manimlib.module_loader import ModuleLoader
 from manimlib.constants import ARROW_SYMBOLS
 from manimlib.constants import DEFAULT_WAIT_TIME
-from manimlib.constants import RED
 from manimlib.event_handler import EVENT_DISPATCHER
 from manimlib.event_handler.event_type import EventType
 from manimlib.logger import log
-from manimlib.reload_manager import reload_manager
-from manimlib.mobject.frame import FullScreenRectangle
 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_embed import interactive_scene_embed
+from manimlib.scene.scene_embed import CheckpointManager
 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
@@ -45,13 +37,14 @@ from manimlib.window import Window
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
-    from typing import Callable, Iterable, TypeVar
+    from typing import Callable, Iterable, TypeVar, Optional
     from manimlib.typing import Vect3
 
     T = TypeVar('T')
 
     from PIL.Image import Image
 
+    from manimlib.reload_manager import ReloadManager
     from manimlib.animation.animation import Animation
 
 
@@ -68,7 +61,6 @@ class Scene(object):
     drag_to_pan: bool = True
     max_num_saved_states: int = 50
     default_camera_config: dict = dict()
-    default_window_config: dict = dict()
     default_file_writer_config: dict = dict()
     samples = 0
     # Euler angles, in degrees
@@ -76,7 +68,6 @@ class Scene(object):
 
     def __init__(
         self,
-        window_config: dict = dict(),
         camera_config: dict = dict(),
         file_writer_config: dict = dict(),
         skip_animations: bool = False,
@@ -84,45 +75,39 @@ class Scene(object):
         start_at_animation_number: int | None = None,
         end_at_animation_number: int | None = None,
         leave_progress_bars: bool = False,
-        preview: bool = True,
+        window: Optional[Window] = None,
+        reload_manager: Optional[ReloadManager] = None,
         presenter_mode: bool = False,
         show_animation_progress: bool = False,
         embed_exception_mode: str = "",
         embed_error_sound: bool = False,
-        existing_window: Window | None = None,
     ):
         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.embed_exception_mode = embed_exception_mode
         self.embed_error_sound = embed_error_sound
+        self.reload_manager = reload_manager
 
         self.camera_config = {**self.default_camera_config, **camera_config}
-        self.window_config = {**self.default_window_config, **window_config}
-        for config in self.camera_config, self.window_config:
-            config["samples"] = self.samples
         self.file_writer_config = {**self.default_file_writer_config, **file_writer_config}
 
-        # Initialize window, if applicable (and reuse window if provided during
+        self.window = window
-        # reload by means of the ReloadManager)
+        if self.window:
-        if self.preview:
+            self.window.init_for_scene(self)
-            if existing_window:
+            # Make sure camera and Pyglet window sync
-                self.window = existing_window
+            self.camera_config["fps"] = 30
-                self.window.update_scene(self)
-            else:
-                self.window = Window(scene=self, **self.window_config)
-                self.camera_config["fps"] = 30  # Where's that 30 from?
-            self.camera_config["window"] = self.window
-        else:
-            self.window = None
 
         # Core state of the scene
-        self.camera: Camera = Camera(**self.camera_config)
+        self.camera: Camera = Camera(
+            window=self.window,
+            samples=self.samples,
+            **self.camera_config
+        )
         self.frame: CameraFrame = self.camera.frame
         self.frame.reorient(*self.default_frame_orientation)
         self.frame.make_orientation_default()
@@ -136,6 +121,7 @@ class Scene(object):
         self.skip_time: float = 0
         self.original_skipping_status: bool = self.skip_animations
         self.checkpoint_states: dict[str, list[tuple[Mobject, Mobject]]] = dict()
+        self.checkpoint_manager: CheckpointManager = CheckpointManager()
         self.undo_stack = []
         self.redo_stack = []
 
@@ -220,80 +206,12 @@ class Scene(object):
         close_scene_on_exit: bool = True,
         show_animation_progress: bool = False,
     ) -> None:
-        if not self.preview:
+        if not self.window:
-            # Embed is only relevant with a preview
+            # Embed is only relevant for interactive development with a Window
             return
-        self.stop_skipping()
-        self.update_frame(force_draw=True)
-        self.save_state()
         self.show_animation_progress = show_animation_progress
 
-        # Create embedded IPython terminal configured to have access to
+        interactive_scene_embed(self)
-        # the local namespace of the caller
-        caller_frame = inspect.currentframe().f_back
-        module = ModuleLoader.get_module(caller_frame.f_globals["__file__"])
-        shell = InteractiveShellEmbed(
-            user_module=module,
-            display_banner=False,
-            xmode=self.embed_exception_mode
-        )
-        self.shell = shell
-
-        # Add a few custom shortcuts to that local namespace
-        local_ns = dict(caller_frame.f_locals)
-        local_ns.update(
-            play=self.play,
-            wait=self.wait,
-            add=self.add,
-            remove=self.remove,
-            clear=self.clear,
-            focus=self.focus,
-            save_state=self.save_state,
-            reload=self.reload,
-            undo=self.undo,
-            redo=self.redo,
-            i2g=self.i2g,
-            i2m=self.i2m,
-            checkpoint_paste=self.checkpoint_paste,
-            touch=lambda: shell.enable_gui("manim"),
-            notouch=lambda: shell.enable_gui(None),
-        )
-
-        # Update the shell module with the caller's locals + shortcuts
-        module.__dict__.update(local_ns)
-
-        # 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")
-
-        # Operation to run after each ipython command
-        def post_cell_func(*args, **kwargs):
-            if not self.is_window_closing():
-                self.update_frame(dt=0, force_draw=True)
-
-        shell.events.register("post_run_cell", post_cell_func)
-
-        # Flash border, and potentially play sound, on exceptions
-        def custom_exc(shell, etype, evalue, tb, tb_offset=None):
-            # Show the error don't just swallow it
-            shell.showtraceback((etype, evalue, tb), tb_offset=tb_offset)
-            if self.embed_error_sound:
-                os.system("printf '\a'")
-            rect = FullScreenRectangle().set_stroke(RED, 30).set_fill(opacity=0)
-            rect.fix_in_frame()
-            self.play(VFadeInThenOut(rect, run_time=0.5))
-
-        shell.set_custom_exc((Exception,), custom_exc)
-
-        # Launch shell
-        shell()
 
         # End scene when exiting an embed
         if close_scene_on_exit:
@@ -616,6 +534,7 @@ class Scene(object):
         self.num_plays += 1
 
     def begin_animations(self, animations: Iterable[Animation]) -> None:
+        all_mobjects = set(self.get_mobject_family_members())
         for animation in animations:
             animation.begin()
             # Anything animated that's not already in the
@@ -623,8 +542,9 @@ class Scene(object):
             # 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.get_mobject_family_members():
+            if animation.mobject not in all_mobjects:
                 self.add(animation.mobject)
+                all_mobjects = all_mobjects.union(animation.mobject.get_family())
 
     def progress_through_animations(self, animations: Iterable[Animation]) -> None:
         last_t = 0
@@ -736,8 +656,6 @@ class Scene(object):
         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
@@ -770,37 +688,6 @@ class Scene(object):
         revert to the state of the scene the first time this function
         was called on a block of code starting with that comment.
         """
-        if self.shell is None or self.window is None:
-            raise Exception(
-                "Scene.checkpoint_paste cannot be called outside of " +
-                "an ipython shell"
-            )
-
-        pasted = pyperclip.paste()
-        lines = pasted.split("\n")
-
-        # Commented lines trigger saved checkpoints
-        if lines[0].lstrip().startswith("#"):
-            if lines[0] not in self.checkpoint_states:
-                self.checkpoint(lines[0])
-            else:
-                self.revert_to_checkpoint(lines[0])
-
-        # Copied methods of a scene are handled specially
-        # A bit hacky, yes, but convenient
-        method_pattern = r"^def\s+([a-zA-Z_]\w*)\s*\(self.*\):"
-        method_names = re.findall(method_pattern ,lines[0].strip())
-        if method_names:
-            method_name = method_names[0]
-            indent = " " * lines[0].index(lines[0].strip())
-            pasted = "\n".join([
-                # Remove self from function signature
-                re.sub(r"self(,\s*)?", "", lines[0]),
-                *lines[1:],
-                # Attach to scene via self.func_name = func_name
-                f"{indent}self.{method_name} = {method_name}"
-            ])
-
         # Keep track of skipping and progress bar status
         self.skip_animations = skip
 
@@ -811,7 +698,7 @@ class Scene(object):
             self.camera.use_window_fbo(False)
             self.file_writer.begin_insert()
 
-        self.shell.run_cell(pasted)
+        self.checkpoint_manager.checkpoint_paste(self)
 
         if record:
             self.file_writer.end_insert()
@@ -820,37 +707,8 @@ class Scene(object):
         self.stop_skipping()
         self.show_animation_progress = prev_progress
 
-    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()
+        self.checkpoint_manager.clear_checkpoints()
-
-    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)
@@ -1006,20 +864,23 @@ class Scene(object):
 
         If `start_at_line` is provided, the scene will be reloaded at that line
         number. This corresponds to the `linemarker` param of the
-        `config.get_module_with_inserted_embed_line()` method.
+        `extract_scene.insert_embed_line_to_module()` method.
 
         Before reload, the scene is cleared and the entire state is reset, such
         that we can start from a clean slate. This is taken care of by the
         ReloadManager, which will catch the error raised by the `exit_raise`
         magic command that we invoke here.
+
         Note that we cannot define a custom exception class for this error,
         since the IPython kernel will swallow any exception. While we can catch
         such an exception in our custom exception handler registered with the
         `set_custom_exc` method, we cannot break out of the IPython shell by
         this means.
         """
-        reload_manager.set_new_start_at_line(start_at_line)
+        self.reload_manager.set_new_start_at_line(start_at_line)
-        self.shell.run_line_magic("exit_raise", "")
+        shell = get_ipython()
+        if shell:
+            shell.run_line_magic("exit_raise", "")
 
     def focus(self) -> None:
         """

manimlib/scene/scene_embed.py

@@ -0,0 +1,151 @@
+import inspect
+import pyperclip
+import re
+
+from IPython.terminal import pt_inputhooks
+from IPython.terminal.embed import InteractiveShellEmbed
+
+from manimlib.animation.fading import VFadeInThenOut
+from manimlib.constants import RED
+from manimlib.mobject.mobject import Mobject
+from manimlib.mobject.frame import FullScreenRectangle
+from manimlib.module_loader import ModuleLoader
+
+
+def interactive_scene_embed(scene):
+    scene.stop_skipping()
+    scene.update_frame(force_draw=True)
+
+    shell = get_ipython_shell_for_embedded_scene(scene)
+    enable_gui(shell, scene)
+    ensure_frame_update_post_cell(shell, scene)
+    ensure_flash_on_error(shell, scene)
+
+    # Launch shell
+    shell()
+
+
+def get_ipython_shell_for_embedded_scene(scene):
+    """
+    Create embedded IPython terminal configured to have access to
+    the local namespace of the caller
+    """
+    # Triple back should take us to the context in a user's scene definition
+    # which is calling "self.embed"
+    caller_frame = inspect.currentframe().f_back.f_back.f_back
+
+    # Update the module's namespace to include local variables
+    module = ModuleLoader.get_module(caller_frame.f_globals["__file__"])
+    module.__dict__.update(caller_frame.f_locals)
+    module.__dict__.update(get_shortcuts(scene))
+
+    return InteractiveShellEmbed(
+        user_module=module,
+        display_banner=False,
+        xmode=scene.embed_exception_mode
+    )
+
+
+def get_shortcuts(scene):
+    """
+    A few custom shortcuts useful to have in the interactive shell namespace
+    """
+    return dict(
+        play=scene.play,
+        wait=scene.wait,
+        add=scene.add,
+        remove=scene.remove,
+        clear=scene.clear,
+        focus=scene.focus,
+        save_state=scene.save_state,
+        reload=scene.reload,
+        undo=scene.undo,
+        redo=scene.redo,
+        i2g=scene.i2g,
+        i2m=scene.i2m,
+        checkpoint_paste=scene.checkpoint_paste,
+    )
+
+
+def enable_gui(shell, scene):
+    """Enables gui interactions during the embed"""
+    def inputhook(context):
+        while not context.input_is_ready():
+            if not scene.is_window_closing():
+                scene.update_frame(dt=0)
+        if scene.is_window_closing():
+            shell.ask_exit()
+
+    pt_inputhooks.register("manim", inputhook)
+    shell.enable_gui("manim")
+
+
+def ensure_frame_update_post_cell(shell, scene):
+    """Ensure the scene updates its frame after each ipython cell"""
+    def post_cell_func(*args, **kwargs):
+        if not scene.is_window_closing():
+            scene.update_frame(dt=0, force_draw=True)
+
+    shell.events.register("post_run_cell", post_cell_func)
+
+
+def ensure_flash_on_error(shell, scene):
+    """Flash border, and potentially play sound, on exceptions"""
+    def custom_exc(shell, etype, evalue, tb, tb_offset=None):
+        # Show the error don't just swallow it
+        shell.showtraceback((etype, evalue, tb), tb_offset=tb_offset)
+        if scene.embed_error_sound:
+            os.system("printf '\a'")
+        rect = FullScreenRectangle().set_stroke(RED, 30).set_fill(opacity=0)
+        rect.fix_in_frame()
+        scene.play(VFadeInThenOut(rect, run_time=0.5))
+
+    shell.set_custom_exc((Exception,), custom_exc)
+
+
+class CheckpointManager:
+    checkpoint_states: dict[str, list[tuple[Mobject, Mobject]]] = dict()
+
+    def checkpoint_paste(self, scene):
+        """
+        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:
+            return
+
+        code_string = pyperclip.paste()
+
+        checkpoint_key = self.get_leading_comment(code_string)
+        self.handle_checkpoint_key(scene, checkpoint_key)
+        shell.run_cell(code_string)
+
+    @staticmethod
+    def get_leading_comment(code_string: str):
+        leading_line = code_string.partition("\n")[0].lstrip()
+        if leading_line.startswith("#"):
+            return leading_line
+        return None
+
+    def handle_checkpoint_key(self, scene, key: str):
+        if key is None:
+            return
+        elif key in self.checkpoint_states:
+            # Revert to checkpoint
+            scene.restore_state(self.checkpoint_states[key])
+
+            # Clear out any saved states that show up later
+            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)
+        else:
+            self.checkpoint_states[key] = scene.get_state()
+
+    def clear_checkpoints(self):
+        self.checkpoint_states = dict()

manimlib/scene/scene_file_writer.py

@@ -146,39 +146,6 @@ class SceneFileWriter(object):
     def get_movie_file_path(self) -> str:
         return self.movie_file_path
 
-    def get_saved_mobject_directory(self) -> str:
-        return guarantee_existence(self.saved_mobject_directory)
-
-    def get_saved_mobject_path(self, mobject: Mobject) -> str | None:
-        directory = self.get_saved_mobject_directory()
-        files = os.listdir(directory)
-        default_name = str(mobject) + "_0.mob"
-        index = 0
-        while default_name in files:
-            default_name = default_name.replace(str(index), str(index + 1))
-            index += 1
-        if platform.system() == 'Darwin':
-            cmds = [
-                "osascript", "-e",
-                f"""
-                set chosenfile to (choose file name default name "{default_name}" default location "{directory}")
-                POSIX path of chosenfile
-                """,
-            ]
-            process = sp.Popen(cmds, stdout=sp.PIPE)
-            file_path = process.stdout.read().decode("utf-8").split("\n")[0]
-            if not file_path:
-                return
-        else:
-            user_name = input(f"Enter mobject file name (default is {default_name}): ")
-            file_path = os.path.join(directory, user_name or default_name)
-            if os.path.exists(file_path) or os.path.exists(file_path + ".mob"):
-                if input(f"{file_path} already exists. Overwrite (y/n)? ") != "y":
-                    return
-        if not file_path.endswith(".mob"):
-            file_path = file_path + ".mob"
-        return file_path
-
     # Sound
     def init_audio(self) -> None:
         self.includes_sound: bool = False

manimlib/window.py

@@ -14,7 +14,7 @@ from manimlib.constants import FRAME_SHAPE
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
-    from typing import Callable, TypeVar
+    from typing import Callable, TypeVar, Optional
     from manimlib.scene.scene import Scene
 
     T = TypeVar("T")
@@ -29,21 +29,22 @@ class Window(PygletWindow):
 
     def __init__(
         self,
-        scene: Scene,
+        scene: Optional[Scene] = None,
         size: tuple[int, int] = (1280, 720),
         samples: int = 0
     ):
-        scene.window = self
         super().__init__(size=size, samples=samples)
 
+        self.scene = scene
         self.default_size = size
         self.default_position = self.find_initial_position(size)
         self.pressed_keys = set()
         self.size = size
 
-        self.update_scene(scene)
+        if self.scene:
+            self.init_for_scene(scene)
 
-    def update_scene(self, scene: Scene):
+    def init_for_scene(self, scene: Scene):
         """
         Resets the state and updates the scene associated to this window.
 
@@ -114,7 +115,7 @@ class Window(PygletWindow):
         py: int,
         relative: bool = False
     ) -> np.ndarray:
-        if not hasattr(self.scene, "frame"):
+        if self.scene is None or not hasattr(self.scene, "frame"):
             return np.zeros(3)
 
         pixel_shape = np.array(self.size)
@@ -145,6 +146,8 @@ class Window(PygletWindow):
     @note_undrawn_event
     def on_mouse_motion(self, x: int, y: int, dx: int, dy: int) -> None:
         super().on_mouse_motion(x, y, dx, dy)
+        if not self.scene:
+            return
         point = self.pixel_coords_to_space_coords(x, y)
         d_point = self.pixel_coords_to_space_coords(dx, dy, relative=True)
         self.scene.on_mouse_motion(point, d_point)
@@ -152,6 +155,8 @@ class Window(PygletWindow):
     @note_undrawn_event
     def on_mouse_drag(self, x: int, y: int, dx: int, dy: int, buttons: int, modifiers: int) -> None:
         super().on_mouse_drag(x, y, dx, dy, buttons, modifiers)
+        if not self.scene:
+            return
         point = self.pixel_coords_to_space_coords(x, y)
         d_point = self.pixel_coords_to_space_coords(dx, dy, relative=True)
         self.scene.on_mouse_drag(point, d_point, buttons, modifiers)
@@ -159,18 +164,24 @@ class Window(PygletWindow):
     @note_undrawn_event
     def on_mouse_press(self, x: int, y: int, button: int, mods: int) -> None:
         super().on_mouse_press(x, y, button, mods)
+        if not self.scene:
+            return
         point = self.pixel_coords_to_space_coords(x, y)
         self.scene.on_mouse_press(point, button, mods)
 
     @note_undrawn_event
     def on_mouse_release(self, x: int, y: int, button: int, mods: int) -> None:
         super().on_mouse_release(x, y, button, mods)
+        if not self.scene:
+            return
         point = self.pixel_coords_to_space_coords(x, y)
         self.scene.on_mouse_release(point, button, mods)
 
     @note_undrawn_event
     def on_mouse_scroll(self, x: int, y: int, x_offset: float, y_offset: float) -> None:
         super().on_mouse_scroll(x, y, x_offset, y_offset)
+        if not self.scene:
+            return
         point = self.pixel_coords_to_space_coords(x, y)
         offset = self.pixel_coords_to_space_coords(x_offset, y_offset, relative=True)
         self.scene.on_mouse_scroll(point, offset, x_offset, y_offset)
@@ -179,32 +190,44 @@ class Window(PygletWindow):
     def on_key_press(self, symbol: int, modifiers: int) -> None:
         self.pressed_keys.add(symbol)  # Modifiers?
         super().on_key_press(symbol, modifiers)
+        if not self.scene:
+            return
         self.scene.on_key_press(symbol, modifiers)
 
     @note_undrawn_event
     def on_key_release(self, symbol: int, modifiers: int) -> None:
         self.pressed_keys.difference_update({symbol})  # Modifiers?
         super().on_key_release(symbol, modifiers)
+        if not self.scene:
+            return
         self.scene.on_key_release(symbol, modifiers)
 
     @note_undrawn_event
     def on_resize(self, width: int, height: int) -> None:
         super().on_resize(width, height)
+        if not self.scene:
+            return
         self.scene.on_resize(width, height)
 
     @note_undrawn_event
     def on_show(self) -> None:
         super().on_show()
+        if not self.scene:
+            return
         self.scene.on_show()
 
     @note_undrawn_event
     def on_hide(self) -> None:
         super().on_hide()
+        if not self.scene:
+            return
         self.scene.on_hide()
 
     @note_undrawn_event
     def on_close(self) -> None:
         super().on_close()
+        if not self.scene:
+            return
         self.scene.on_close()
 
     def is_key_pressed(self, symbol: int) -> bool: