How to change gravity?

[fabkury]

I wanted to make some animated GIFs using this tool, if that's ok.

Imagine for example an hourglass. I wanted to be able to turn it upside down.

I can easily turn an image upside down, outside of the tool (e.g. in GIMP), but would there be an easy way to change the direction of gravity in the simulation?

If I can have full control of gravity, I can rotate the images "in post production" in sync with the change in the direction of gravity, hence simulating a real rotation of an hourglass.

I am not experienced with Javascript, but I code in other languages. I can try to implement the gravity chanmge feature in a rough-but-works way if needed.

[Hartrik]

Yes, why not :)

However, the gravity direction is somewhat hardcoded in the simulation, and there isn't a straightforward way to change it. A simpler approach might be to mirror flip the content of the canvas, which could simulate the effect you're looking for

[fabkury]

Thanks :)
I see what you're saying. Would you mind giving me a general direction to go, if I am to implement that myself?

[Hartrik]

You can add a flip button into dev/test tools. See how Fill is implemented in gui/ComponentViewTestTools. Re-introduce this method that I recently deleted. Create an action similar to gui/ActionFill – use sandGame and sandGame.graphics() ...

If you do it this way and want to create a pull request, I will approve it