# An add-on to calculate mass of complex 3D mesh?

For example, i have non manifold mesh, and want to compute the mass of mesh like if it is made of steel or wood.
Is there such add-on? Or may be i can use some other program, or online service?

i might have found one method, but im not in the mood of doing math and shitâŚ so ill let that up to you.
if the following statement is true, then my method works.

DO THE MATH TO CHECK!
Statement:
A cube that is 2x2x2 meters made of solid gold will have a mass of 154.256tonn

method:
select the mesh, apply scale by hitting CTRL + A, go to the physics tab in the properties and enable Rigid Body, then in the tools panel, go to physics and click Calculate mass (in this case i selected gold), then look in the rigid body properties and there should be a Mass value. from there you can find the density of whatever material you chose, and from there you can calculate the volume.

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also, turn on metric units if you havent already

Many thanks finalbarrage Stadard 2x2x2 meters cube made of steel is 62.88 ton

If the mesh is non manifold, wouldnât that make getting a mass impossible?

I donât know. I never try to calculate mass of non-manifold mesh.

Itâs easy, add a fluid sim and inflow, fill the non manifold mesh with honey, delete the mesh, apply the fluid sim, 3-d print the fluid sim mesh, weight it on a triple beam balance, and then divide by the plasticâs density.

for non manifold you must separate the different parts to get manifold meshes
then you can calculate the volume and sum all the parts
there is a script some where to calculate volume for manifold mesh

happy bl

I think I misunderstood your original post, were you asking for a way to get the value for a mesh that is not closed?

No chrisd i was asking how i can calculate mass of non-manifold (water-proof) mesh.

Waterproof does not say if it is manifold or not

happy bl

Alternative

Ď = m / V

Ď = density (kg/m[SUP]3[/SUP])
m = mass (kg)
V = volume (m[SUP]3[/SUP])

So all you need is to get the Volume

2. MeshLab has: ââŚ a measurement filter that computes volume, surface, inertia tensor, topological invariants, manifoldness etc etc.â

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watertight and manifold, I believe, are the same thing

EDIT I should say closed manifold, as there can be open manifolds as well

as I remember watertight just means closed volume and no holes !
can be manifold or not !

happy bl

well point was you can use this method to gain data to calculate the volume and mass of whatever object you want.
even non-uniform once.