Hi Ferdinand,

I just wanted to thank you for your invaluable help! Thanks to your guidance, I was able to solve my issue with toggling the default gravity in Cinema 4D. Honestly, I didn't think it would be this complicated!

For anyone who might encounter a similar problem, here's the script I used, based on your code. It allows access to the global default simulation scene in the simulation hook and toggles the gravity value between 0 and -981:

import c4d

doc: c4d.documents.BaseDocument  # The currently active document.
op: c4d.BaseObject | None  # The primary selected object in the document. Can be None.

c4d.SHsimulation: int = 1057220  # The ID of the simulation hook.

def main() -> None:
    """Called by Cinema 4D when the script is executed."""
    
    # Get the simulation hook of the active document
    simulationHook: c4d.BaseList2D | None = doc.FindSceneHook(c4d.SHsimulation)
    if not simulationHook:
        raise RuntimeError("Cannot find the simulation hook.")
    
    # Retrieve the object branch from the simulation hook
    branches: list[dict] = simulationHook.GetBranchInfo()
    data: dict | None = next(n for n in branches if n["id"] == c4d.Obase)  # We're looking for the object branch.
    if not data:
        raise RuntimeError("Malformed simulation hook with missing object branch.")
    
    # Get the simulation scene
    simulationScene: c4d.BaseObject | None = data["head"].GetFirst()
    if not simulationScene:
        raise RuntimeError("Malformed simulation hook with missing object branch children.")
    
    # Toggle gravity between 0 and -981
    if simulationScene[c4d.PBDSCENE_DEFAULTGRAVITY] == 0:
        simulationScene[c4d.PBDSCENE_DEFAULTGRAVITY] = -981
    else:
        simulationScene[c4d.PBDSCENE_DEFAULTGRAVITY] = 0

    c4d.EventAdd()

if __name__ == '__main__':
    main()

This script toggles the default gravity of the simulation scene between 0 and -981 depending on its current value.

Thanks again for your help! I hope this can be useful to others who might face the same issue.

Hi everyone,

I'm working on a Python script in Cinema 4D and I'm trying to toggle the default gravity of the scene between 0 and -981. I've tried several approaches, but I can't seem to find the correct method to access and modify this value.

Here's what I've attempted so far:

from typing import Optional
import c4d

doc: c4d.documents.BaseDocument  # The active document
op: Optional[c4d.BaseObject]  # The active object, None if unselected

def main() -> None:
    def object() -> Optional[c4d.BaseObject]:
        return doc.GetActiveObject()

    active_object = object()
    if not active_object:
        return

    current_gravity = active_object[c4d.PBDSCENE_DEFAULTGRAVITY]
    if current_gravity == 0:
        active_object[c4d.PBDSCENE_DEFAULTGRAVITY] = -981
    else:
        active_object[c4d.PBDSCENE_DEFAULTGRAVITY] = 0

if __name__ == '__main__':
    main()
    c4d.EventAdd()

Unfortunately, this doesn't work. If anyone can point me to the correct way to access and modify this value, that would be great!

Thanks in advance for your help!