I tried to add the same mesh to multiple geometry objects and got strange results. I suppose that this is not the correct way. What to do? Make deep clone of mesh or is only deep clone of a geometry object allowed if there is already a mesh attached to it?
if it has animation use deep clone().
if you wont change the geometry parameters you dont need to clone().
There’s very little cases where you need to use deepClone().
In your case, you just need to set the same mesh on two geometries.
Taking a step back, you say: “I tried to add the same mesh to multiple geometry objects and got strange results.”
Can you tell us what the strange results were?