[FEATURE] Allow to complete loop before going to next slide

[jeertmans]

Discussed in #252

^{Originally posted by torannn August 23, 2023}
I've seen a similar project named Manim Editor. I think the feature complete_loop is quite useful. Currently, if we use the loop and press the next button, the animation will end immediately. It creates an unsmooth transition between animations. I think we can create the complete_loop feature similar to Manim Editor. When the user press the next button, the complete_loop force the animation to be finished, then continue running the next animation.
You can check out the example created by manim editor here https://manimcommunity.github.io/manim_editor/Tutorial/index.html.

[zain93393]

I would like to work on this issue. I'd appreciate some guidance as I'm new to open source.

[jeertmans]

Hello @zain93393, thanks for your interest in helping me!

First, make sure to read the contributing guide.

Next, you should only edit the code in https://github.com/jeertmans/manim-slides/blob/main/manim_slides/present/.

The idea I propose it to have a CLI option --next-terminates-loops that will allow user to turn a loop into a plain slide (i.e., not looping) upon pressing NEXT.

This is the code that is processed when pressing NEXT:

manim-slides/manim_slides/present/player.py

Lines 298 to 303 in bbe8b96

	@Slot()
	def next(self) -> None:
	if self.media_player.playbackState() == QMediaPlayer.PausedState:
	self.media_player.play()
	else:
	self.load_next_slide()

I think you should modify the else clause to something like

elif self.next_terminates_loops and self.medial_player.loops() != 1:
    self.media_player.setLoops(1)
else:
    self.load_next_slide() 

Of course, you will need to add a new option to the Player's __init__ method:

manim-slides/manim_slides/present/player.py

Lines 42 to 55 in bbe8b96

	def __init__(
	self,
	config: Config,
	presentation_configs: List[PresentationConfig],
	*,
	start_paused: bool = False,
	full_screen: bool = False,
	skip_all: bool = False,
	exit_after_last_slide: bool = False,
	hide_mouse: bool = False,
	aspect_ratio_mode: Qt.AspectRatioMode = Qt.KeepAspectRatio,
	presentation_index: int = 0,
	slide_index: int = 0,
	screen: Optional[QScreen] = None,

Finally, you need to add a CLI option to

manim-slides/manim_slides/present/__init__.py

Lines 220 to 233 in bbe8b96

	def present(
	scenes: List[str],
	config_path: Path,
	folder: Path,
	start_paused: bool,
	full_screen: bool,
	skip_all: bool,
	exit_after_last_slide: bool,
	hide_mouse: bool,
	aspect_ratio: str,
	start_at: Tuple[Optional[int], Optional[int], Optional[int]],
	start_at_scene_number: int,
	start_at_slide_number: int,
	screen_number: Optional[int] = None,

and document it (see other click.option as examples) so that the user can specify the option via the terminal.

Tell me if you need further help :-)

[zain93393]

hey @jeertmans, this error is coming up when I am trying to push the changes

can you help me with this?

[jeertmans]

Seems that you are trying to push your virtual environment, which contains very large files, which you should not do.

Usually, you want to ignore that folder, by adding a new line to .gitignore.

Check the Undoing Your Last Commit (That Has Not Been Pushed) section, to undo your commit. Next, modify .gitignore to include your virtual env. Then, re-commit your files and push.

[jeertmans]

After testing, I am afraid this might not be possible: QMediaPlayer.setLoops(1) does not seem to apply to the current loop. Actually, setting the loop to 1 finishes the current loop, and does two more loops before reaching EndOfMedia. I will open a PR showing my work, but this does not work at the moment.