Merge pull request #336 from mertyildiran/master

Live streaming and interactive shell

README.md

@@ -69,3 +69,18 @@ a Dockerfile provided.
 On a Windows system, make sure to replace `$PWD` with an absolute path to manim.
 
 Note that the shipped Docker image contains the bare requirements to run manim. To transform the Docker container into a fully-functioning development environment, you will have to edit your personal Dockerfile a bit. For a guide to create your own personal Docker image, consult [this guide to Dockerfiles](https://www.howtoforge.com/tutorial/how-to-create-docker-images-with-dockerfile/).
+
+## Live Streaming
+
+To live stream your animations, simply assign `IS_LIVE_STREAMING = True` in `constants.py` file and from your Python Interactive Shell (`python3`) import the stream starter with `from stream_starter import *` while under the project directory. This will provide a clean interactive shell to enter your commands. `manim` object is a `Manim()` instance so as soon as you play an animation with `manim.play()` your stream will start. A video player will pop-up and you can broadcast that video using [OBS Studio](https://obsproject.com/) which is the most practical way of streaming with this math animation library. An example:
+
+```
+>>> from stream_starter import *
+YOUR STREAM IS READY!
+>>> circle = Circle()
+>>> manim.play(ShowCreation(circle))
+Animation 0: ShowCreationCircle: 100%|███████████████████████████████████████████████████████████████████████████████████████████████████████████████████████| 60/60 [00:01<00:00, 37.30it/s]
+<scene.scene.Scene object at 0x7f0756d5a8d0>
+```
+
+It is also possible to stream directly to Twitch. To do that simply assign `IS_STREAMING_TO_TWITCH = True` in `constants.py` file and put your Twitch Stream Key to `TWITCH_STREAM_KEY = "YOUR_STREAM_KEY"` and when you follow the above example the stream will directly start on your Twitch channel(with no audio support).

animation/creation.py

@@ -98,6 +98,7 @@ class Write(DrawBorderThenFill):
             mobject = TextMobject(mob_or_text)
         else:
             mobject = mob_or_text
+
         if "run_time" not in kwargs:
             self.establish_run_time(mobject)
         if "lag_factor" not in kwargs:

constants.py

@@ -213,3 +213,13 @@ PALETTE = list(COLOR_MAP.values())
 locals().update(COLOR_MAP)
 for name in [s for s in list(COLOR_MAP.keys()) if s.endswith("_C")]:
     locals()[name.replace("_C", "")] = locals()[name]
+
+# Streaming related configurations
+IS_LIVE_STREAMING = False
+LIVE_STREAM_NAME = "LiveStream"
+IS_STREAMING_TO_TWITCH = False
+TWITCH_STREAM_KEY = "YOUR_STREAM_KEY"
+STREAMING_PROTOCOL = "tcp"
+STREAMING_IP = "127.0.0.1"
+STREAMING_PORT = "2000"
+STREAMING_CLIENT = "ffplay"

manim.py

@@ -0,0 +1,31 @@
+#!/usr/bin/python3
+
+from constants import *
+from scene.scene import Scene
+
+
+class Manim():
+
+    def __new__(cls):
+        kwargs = {
+            "scene_name": LIVE_STREAM_NAME,
+            "open_video_upon_completion": False,
+            "show_file_in_finder": False,
+            # By default, write to file
+            "write_to_movie": True,
+            "show_last_frame": False,
+            "save_pngs": False,
+            # If -t is passed in (for transparent), this will be RGBA
+            "saved_image_mode": "RGB",
+            "movie_file_extension": ".mp4",
+            "quiet": True,
+            "ignore_waits": False,
+            "write_all": False,
+            "name": LIVE_STREAM_NAME,
+            "start_at_animation_number": 0,
+            "end_at_animation_number": None,
+            "skip_animations": False,
+            "camera_config": HIGH_QUALITY_CAMERA_CONFIG,
+            "frame_duration": MEDIUM_QUALITY_FRAME_DURATION,
+        }
+        return Scene(**kwargs)

scene/scene.py

@@ -7,13 +7,18 @@ import random
 import shutil
 import subprocess as sp
 import warnings
+from time import sleep
+try:
+    import thread  # Low-level threading API (Python 2.7)
+except ImportError:
+    import _thread as thread  # Low-level threading API (Python 3.x)
 
 from tqdm import tqdm as ProgressDisplay
 
 from constants import *
 
 from animation.animation import Animation
-from animation.transform import MoveToTarget
+from animation.transform import MoveToTarget, ApplyMethod
 from camera.camera import Camera
 from continual_animation.continual_animation import ContinualAnimation
 from mobject.mobject import Mobject
@@ -24,6 +29,9 @@ from utils.output_directory_getters import get_image_output_directory
 
 from container.container import Container
 
+from mobject.svg.tex_mobject import TextMobject
+from animation.creation import Write
+import datetime
 
 class Scene(Container):
     CONFIG = {
@@ -58,6 +66,7 @@ class Scene(Container):
         self.frame_num = 0
         self.current_scene_time = 0
         self.original_skipping_status = self.skip_animations
+        self.stream_lock = False
         if self.name is None:
             self.name = self.__class__.__name__
         if self.random_seed is not None:
@@ -67,6 +76,8 @@ class Scene(Container):
         self.setup()
         if self.write_to_movie:
             self.open_movie_pipe()
+        if IS_LIVE_STREAMING:
+            return None
         try:
             self.construct(*self.construct_args)
         except EndSceneEarlyException:
@@ -453,6 +464,8 @@ class Scene(Container):
                 raise EndSceneEarlyException()
 
     def play(self, *args, **kwargs):
+        if IS_LIVE_STREAMING:
+            self.stream_lock = False
         if len(args) == 0:
             warnings.warn("Called Scene.play with no animations")
             return
@@ -489,8 +502,25 @@ class Scene(Container):
         else:
             self.continual_update(0)
         self.num_plays += 1
+
+        if IS_LIVE_STREAMING:
+            self.stream_lock = True
+            thread.start_new_thread(self.idle_stream, ())
+
         return self
 
+    def idle_stream(self):
+        while(self.stream_lock):
+            a = datetime.datetime.now()
+            self.update_frame()
+            n_frames = 1
+            frame = self.get_frame()
+            self.add_frames(*[frame] * n_frames)
+            b = datetime.datetime.now()
+            time_diff = (b - a).total_seconds()
+            if time_diff < self.frame_duration:
+                sleep(self.frame_duration - time_diff)
+
     def clean_up_animations(self, *animations):
         for animation in animations:
             animation.clean_up(self)
@@ -608,6 +638,7 @@ class Scene(Container):
             '-pix_fmt', 'rgba',
             '-r', str(fps),  # frames per second
             '-i', '-',  # The imput comes from a pipe
+            '-c:v', 'h264_nvenc',
             '-an',  # Tells FFMPEG not to expect any audio
             '-loglevel', 'error',
         ]
@@ -622,6 +653,14 @@ class Scene(Container):
                 '-vcodec', 'libx264',
                 '-pix_fmt', 'yuv420p',
             ]
+        if IS_LIVE_STREAMING:
+            if IS_STREAMING_TO_TWITCH:
+                command += ['-f', 'flv']
+                command += ['rtmp://live.twitch.tv/app/' + TWITCH_STREAM_KEY]
+            else:
+                command += ['-f', 'mpegts']
+                command += [STREAMING_PROTOCOL + '://' + STREAMING_IP + ':' + STREAMING_PORT]
+        else:
             command += [temp_file_path]
         # self.writing_process = sp.Popen(command, stdin=sp.PIPE, shell=True)
         self.writing_process = sp.Popen(command, stdin=sp.PIPE)
@@ -629,11 +668,21 @@ class Scene(Container):
     def close_movie_pipe(self):
         self.writing_process.stdin.close()
         self.writing_process.wait()
+        if IS_LIVE_STREAMING:
+            return True
         if os.name == 'nt':
             shutil.move(*self.args_to_rename_file)
         else:
             os.rename(*self.args_to_rename_file)
 
+    def tex(self, latex):
+        eq = TextMobject(latex)
+        anims = []
+        anims.append(Write(eq))
+        for mobject in self.mobjects:
+            anims.append(ApplyMethod(mobject.shift,2*UP))
+        self.play(*anims)
+
 
 class EndSceneEarlyException(Exception):
     pass

stream_starter.py

@@ -0,0 +1,13 @@
+from big_ol_pile_of_manim_imports import *
+import subprocess
+from time import sleep
+from manim import Manim
+
+if not IS_STREAMING_TO_TWITCH:
+    FNULL = open(os.devnull, 'w')
+    subprocess.Popen([STREAMING_CLIENT, STREAMING_PROTOCOL + '://' + STREAMING_IP + ':' + STREAMING_PORT + '?listen'], stdout=FNULL, stderr=FNULL)
+    sleep(3)
+
+manim = Manim()
+
+print("YOUR STREAM IS READY!")