Variable framerate fix for all branches

[qo4on]

1. Manim generates variable framerate video instead of the constant value in the CONFIG

2. mp4fpsmod tool can fix this. Unzip the attachment to manim folder and place this code to line 502 of scene_file_writer.py right after combine_process.wait().

Note: this tool does not work if you have opened the video file in another program.

mp4fpsmod_file_path = os.path.join(
    os.getcwd(),
    'mp4fpsmod.exe' if os.name == 'nt' else 'mp4fpsmod'
)

fix_timestamps_process = subprocess.Popen([
    mp4fpsmod_file_path,
    '--fps', '0:' + str(self.scene.camera.frame_rate),
    '--timescale', '15360',
    movie_file_path, '--inplace'
])
fix_timestamps_process.wait()

mp4fpsmod.zip

[TonyCrane]

I think you may have made a mistake, why did you make a pull request from the shaders branch to the master. If you are actually mistaken, please close this pull request.

[qo4on]

Yes, sorry.
I made a correct pr.