Unreal Scale?

Hmmm, after merging in one of your samples into my character scene, Ragdoll characters are 1/9th the scale of an Unreal Engine character.

This would explain the massive discrepancy in the limit behavior I was experiencing considering the ‘mass’-ive difference in the Mass of the Markers on my character versus yours…magnitudes in fact (my characters arm has a mass of 2647!)

I included that old Pirate rig as I suspected the Ragdoll demos were using the smaller scale.

So what’s going on here and what do we do? Crank everything up proportionally?


There is a global multiplier you can try under the solver Attribute Editor.

Not sure what I’m looking at that helps here? Unreal (Human) characters are 180 cm, so according to Ragdoll these are massive, if going by all your sample characters.

How can we easily compensate for this so we get performance and accuracy out of our as demonstrated in your samples?

I’m having trouble understanding what you are looking for. Could you mean the Scene Scale attribute on the solver?

If a character has 10% of the size of a real-world character, such as 18 cm rather than 180 cm, then the Scene Scale value should be 0.1. If your character is 100% the size already, then the value can be 1.0 instead. The example characters are all 10% of real-world scale.


If you are able to upload a video of what you are seeing, and if possible another video of what you would like to achieve, then that would help narrow down what it is you are looking for.

This isn’t a video thing, just talking numbers. Now, something tells me that this:

…is a LOT of mass for what is otherwise just a ‘human scale’ character at 180cm? Regardless if Scene Scale is set to 0.1 or 1.0, that number never changes. (To be clear, that’s my Unreal engine scale character of 180 cm)

In all of your example Ragdolls, they are tiny and have very little mass. I’m just curious why you opted to demonstrate Ragdoll with a 0.1 Scene Scale and 20 cm characters, as that would lead me to believe that might be an ideal way to work with Ragdoll?

So with “human sized” characters, how important is the Mass value? Does the physics system see me moving around a massive character, or is the number merely relative to other objects during interactions? Does Mass have any affect on either Limits or Interactive Mode or both? (the two things I’m having difficulty with)

Thank you Marcus!


This was a challenge, as every studio has their own preference on scale. Some operate at 10%, some at 100%, others at 33.2% or other arbitrary values. So we had to pick one, and stick to it. In my professional experience, and the past few years of serving Ragdoll customers, 10% has been the most common scale; roughly 4/5 of studios uses it. So most of the time, scale is not anything that comes to mind.

But when it does, things need explanation, like this Mass value you’ve found. To Ragdoll, these are not kilograms or pounds; they are Ragdoll units. To Ragdoll, it is not important how large they are, only how they relate to each other. If one object has a mass of 100 and another a mass of 10, then one of them is 10x as heavy as the other. Meaning that if you put these two on a see-saw, the heavier one will reach the ground.

The one casualty however are limits; they are affected by the overall mass of each Marker and normally the best thing to do is either increase the Limit Stiffness by a factor of 10 to 1000, depending on taste. That global value on the solver can help shift the balance on all limits at once and should generally be enough.

Okay cool. I’m clearly biased, assuming EVERYone does game animation, and by that virtue uses Unreal if not Unity, and therefore would want to about by the unit/cm paradigm!

Now, I did find that turning Density down to 0.0 allows for custom Mass to be entered. Is this also a viable avenue to help with the same issues with the Limits? (which is exactly what my issue has been)