Make manim crash when ffmpeg crashes (#546)

* make manim crash when ffmpeg crashes

* lol black

* removed Example3DNo1 for not breaking the docs

* Quick test with all 3d scenes removed

* re added 3d scene

* woah that was hard to debug

* fix underlines

* woah THAT was hard to debug

* black

* blackest night

* do the other call too

* I just want to re-trigger the RTD build

Co-authored-by: kolibril13 <[email protected]>

Author: leotrs

docs/source/examples/3d.rst

@@ -78,4 +78,3 @@
             self.add(axes, curve1)
             self.set_camera_orientation(phi=80 * DEGREES, theta=-60 * DEGREES)
             self.wait()
-

docs/source/installation/linux.rst

@@ -11,7 +11,7 @@ The two necessary dependencies are cairo and ffmpeg.  LaTeX is strongly
 recommended, as it is necessary to have access to the ``Tex`` and ``MathTex`` classes.
 
 Ubuntu/Mint/Debian
-*************
+******************
 
 Before installing anything, make sure that your system is up to date.
 
@@ -42,15 +42,15 @@ To install LaTeX:
 If you don't have python3-pip installed, install it:
 
 .. code-block:: bash
-   
+
    sudo apt install python3-pip
-  
+
 .. note:: These instructions are also valid for other Debian-based
           distributions or distributions that use the ``apt`` package manager.
 
 
 Fedora/CentOS/RHEL
-*************
+******************
 
 To install cairo:
 
@@ -116,7 +116,7 @@ To install LaTeX:
 If you don't have python-pip installed, install it:
 
 .. code-block:: bash
-   
+
    sudo pacman -S python-pip
 
 

docs/source/manim_directive.py

@@ -168,6 +168,14 @@ def run(self):
         video_dir = os.path.join(media_dir, "videos")
         output_file = f"{clsname}-{classnamedict[clsname]}"
 
+        # Important: note that all scenes are being rendered on the same python
+        # interpreter.  That means that each time we change the config, that
+        # same config will be used for the next scene.  For this reason, we
+        # have to make sure to restore the original config after each scene.
+        save_config_code = [
+            "original_config = copy.deepcopy(config)",
+            "original_fw_config = copy.deepcopy(file_writer_config)",
+        ]
         file_writer_config_code = [
             f'config["frame_rate"] = {frame_rate}',
             f'config["pixel_height"] = {pixel_height}',
@@ -181,6 +189,14 @@ def run(self):
             f'file_writer_config["save_as_gif"] = {save_as_gif}',
             f'file_writer_config["output_file"] = "{output_file}"',
         ]
+        file_writer_config_code.append(
+            'file_writer_config["write_to_movie"] = '
+            + ("False" if save_last_frame else "True")
+        )
+        restore_config_code = [
+            "config = original_config",
+            "file_writer_config = original_fw_config",
+        ]
 
         user_code = self.content
         if user_code[0].startswith(">>> "):  # check whether block comes from doctest
@@ -190,9 +206,12 @@ def run(self):
 
         code = [
             "from manim import *",
+            f"logger.info('rendering {clsname}')",
+            *save_config_code,
             *file_writer_config_code,
             *user_code,
             f"{clsname}().render()",
+            *restore_config_code,
         ]
         exec("\n".join(code), globals())
 

manim/constants.py

@@ -1,6 +1,4 @@
-"""
-Constant definitions.
-"""
+"""Constant definitions."""
 
 import numpy as np
 

manim/scene/scene_file_writer.py

@@ -544,8 +544,11 @@ def combine_movie_files(self):
         if not self.includes_sound:
             commands.insert(-1, "-an")
 
-        combine_process = subprocess.Popen(commands)
-        combine_process.wait()
+        try:
+            subprocess.check_call(commands)
+        except subprocess.CalledProcessError as exc:
+            logger.error(f"FFMPEG returned with code {exc.returncode}")
+            raise exc
 
         if self.includes_sound:
             sound_file_path = movie_file_path.replace(
@@ -582,7 +585,12 @@ def combine_movie_files(self):
                 # "-shortest",
                 temp_file_path,
             ]
-            subprocess.call(commands)
+            try:
+                subprocess.check_call(commands)
+            except subprocess.CalledProcessError as exc:
+                logger.error(f"FFMPEG returned with code {exc.returncode}")
+                raise exc
+
             shutil.move(temp_file_path, movie_file_path)
             os.remove(sound_file_path)
 

manim/utils/caching.py

@@ -36,16 +36,21 @@ def wrapper(self, scene, *args, **kwargs):
             hash_play = get_hash_from_play_call(
                 self, self.camera, animations, mobjects_on_scene
             )
-            if self.file_writer.is_already_cached(hash_play):
-                logger.info(
-                    f"Animation {self.num_plays} : Using cached data (hash : %(hash_play)s)",
-                    {"hash_play": hash_play},
-                )
-                file_writer_config["skip_animations"] = True
+            if file_writer_config["write_to_movie"]:
+                if self.file_writer.is_already_cached(hash_play):
+                    logger.info(
+                        f"Animation {self.num_plays} : Using cached data (hash : %(hash_play)s)",
+                        {"hash_play": hash_play},
+                    )
+                    file_writer_config["skip_animations"] = True
         else:
             hash_play = "uncached_{:05}".format(self.num_plays)
         self.animations_hashes.append(hash_play)
-        self.file_writer.add_partial_movie_file(hash_play)
+        if (
+            not file_writer_config["disable_caching"]
+            and file_writer_config["write_to_movie"]
+        ):
+            self.file_writer.add_partial_movie_file(hash_play)
         logger.debug(
             "List of the first few animation hashes of the scene: %(h)s",
             {"h": str(self.animations_hashes[:5])},
@@ -84,15 +89,20 @@ def wrapper(self, scene, duration=DEFAULT_WAIT_TIME, stop_condition=None):
             hash_wait = get_hash_from_wait_call(
                 self, self.camera, duration, stop_condition, scene.get_mobjects()
             )
-            if self.file_writer.is_already_cached(hash_wait):
-                logger.info(
-                    f"Wait {self.num_plays} : Using cached data (hash : {hash_wait})"
-                )
-                file_writer_config["skip_animations"] = True
+            if file_writer_config["write_to_movie"]:
+                if self.file_writer.is_already_cached(hash_wait):
+                    logger.info(
+                        f"Wait {self.num_plays} : Using cached data (hash : {hash_wait})"
+                    )
+                    file_writer_config["skip_animations"] = True
         else:
             hash_wait = "uncached_{:05}".format(self.num_plays)
         self.animations_hashes.append(hash_wait)
-        self.file_writer.add_partial_movie_file(hash_wait)
+        if (
+            not file_writer_config["disable_caching"]
+            and file_writer_config["write_to_movie"]
+        ):
+            self.file_writer.add_partial_movie_file(hash_wait)
         logger.debug(
             "List of the first few animation hashes of the scene: %(h)s",
             {"h": str(self.animations_hashes[:5])},