Issues of scale

[sanform]

I'm using the "3D Cross Platform Determistic" version of Rapier making a game where I need to detect collisions of an object a cylinder with a radious of .02 meters. I'm seeing the object penetrate the surface it's resting on and issues with Area3D detection. I'm using the stability preset. Are there other changes needed to deal with simulations of this scale?

[Ughuuu]

Hi, if the unit of measure is 0.02 radius for the cylinder, you can update if you want some project settings to make things react better at smaller scale. There is 1 setting you can try, eg. PIXEL_PER_METER or something like that. That one for 2d is 100 (because in 2d 100 pixels are 1 meter) and for 3d is 1 (because 1 pixel is 1 meter). You can try it with 0.1 or 0.01, see if it improves the simulation.

[sanform]

I was able to find "LENGTH_UNIT_VALUE" in the source and "physics/rapier/solver/length_unit_3d" the editor. The editor doesn't seem to want to allow floating point precision for "length_unit_3d". Would a change like this involve the gravity setting too?

[Ughuuu]

Hi. Not 100% sure, you will need to check the source code to see, but I think yes.
About the float point precision, that should be an easy enough fix also. Open an issue for that one.

[sanform]

Thanks! #481