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Cloth simulation machine units scale is off.. it have to be 10 times smaller
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Description

Operating system: Win10
Graphics card: Nvidia 1060

Blender Version
Broken: v2.80.248

Short description of error
Cloth simulation machine units scale is off.. it have to be 10 times smaller

Exact steps for others to reproduce the error
If you want to make a Simulation off a piece of canvas there is a square meter,you have to make it Ten times bigger (10m x10m).
Then default presetting for canvas works, as Long as you don't change the settings for the mass, it should be 10 times less Around 0.2 to 0.3 kg

Related Objects

Event Timeline

Personally I think the default scale of Blender is way too big..
The default cube is 2x2x2 meters, When You Look at a screen without any reference to compare with,you will properly think It is a lot smaller.
I'm guessing between 2x2x2cm and 20x20x20cm depending of the size of the screen you are working on.
but I don't think anyone with ges in the meters range

Brecht Van Lommel (brecht) lowered the priority of this task from Needs Triage by Developer to Needs Information from User.Mar 16 2019, 6:17 PM

Can you describe exactly what the bug is? What fails if you don't make it bigger? It seems to work fine here.

Here is two file/scenes with baked in keyframes - world scene scale is 1.0
if I change the scene scale to 0.1 the Mass is 0.0003kg and max out at 0.01kg

Philipp Oeser (lichtwerk) raised the priority of this task from Needs Information from User to Needs Triage by Developer.Mar 27 2019, 12:28 PM
Sebastian Parborg (zeddb) lowered the priority of this task from Needs Triage by Developer to Confirmed, Medium.

The weight of the cloth sim is indeed scaled too much it seems.

This is actually the correct behavior.

The mass is calculated as mass = density * volume and volume = m^3. So if you scale the scene to 0.1 units, the new mass will be oldmass * 0.1^3 = 0.3kg * 0.1^3 = 0.0003kg

My bad now I see the issue. The weight can't go up higher than 0.01kg.

@Brecht Van Lommel (brecht) this is really old, but do you remember why we cap the weight rB6ec52fc1b573e2904d7d08728f120589b649a08b ?

I'm guessing it has to do with simulation stability etc.

There's no good reason I imagine, it's easy to get unstable simulations anyway. That commit is porting things from even older UI code that had these limits. Just remove the limits.