NewtonBodyAddBuoyancyFo water settings

[PJani]

What settings to use for water buoyancy if 1unit = 1meter. i have set density 1000kg/m^3 but i dont have idea what to set for fluidLinearViscosity and fluisAngularViscosity.

When i drop 0.2m^3(200 liter) empty barrel with mass 20kg from 100meters barrel jumps outof water like rocket. 10meters high.

[Julio Jerez]

you can use trial an error.

when using boyuancy you cans no really gon by teh density and volume, because density is a volumetric quantity teh quicky crate very large mass value,
and that eassitly brake the floating point precitions.

I worte a doc of hwo to usin scaling, but essentcially you can save a water density with teh body, and usin fo each body.
say you havce a body of side A and one side 2 * A,
to obey the Mas/desnsity equation you will have to have the secund body 8 time heavier than the first body, so the ratio goes quite fast.
if instead secund body is only twice as heavy it will float a lot more, but you can scale it water density and make lighter, that way thewill sink mopre will displace more volume.

[PJani]

This means more lines of code in my force callback?

[Julio Jerez]

no, all you need to save is a scale factor for for the Body Volume with the body.

so for body one the density is bodyScale * fluidDentity
so for body one the density is bodyScale * fluidDentity