Body Physics in FO4

[Gawdzila]

I think there may be a solution for the body physics that has eluded Fallout 4 thus far.

 

If I remember correctly, the major difficulty of implementing physics in FO4 was the number of bones available in the bodies, and the limits on weights inherent to those bones.  Well, having recently upgraded my Skyrim installation to the Special Edition, I soon discovered that the physics plugin that everyone knew and loved, HDT-PE, was no longer functioning with it, either.

 

However, I also found out that the original creator also made a new physics engine, HDT-SMP -- Skinned Mesh Physics -- which functions using Bullet instead of Havok.  The great and helpful feature of this is that it doesn't, as I understand it, require doing anything to the bones at all to do physics; it simply uses the model itself as a collision mesh, with all physics parameters defined in a separate file.  This whole setup requires just the framework (Script Extender plugin .dlls), some weight-painted models, a set of .xml files that reference the shapes in the models, and of course a compatible skeleton.

 

I, unfortunately, do not have even the most basic requisite programming knowledge to even think about implementing SMP for FO4, nor even enough to know whether it is possible.  For anyone who might be interested in investigating it, though, I can at least gather the necessary resources in one spot.  Keep in mind this is all Skyrim-based stuff.

 

 

1) SMP Framework:

SMP Physics Framework: http://www.9damao.com/thread-61877-1-1.html

SMP Mesh Physics: http://www.9damao.com/thread-61878-1-1.html

 

This is a Chinese site (Google translate works well enough to get through it), you can just register with a fake e-mail; all you need to do is post one reply in the thread in order to be able to download stuff.

 

2)  A weight-painted body like CBBE.  To see how this works, it might be best to download the Skyrim CBBE body since SMP actually works on it (https://www.nexusmods.com/skyrimspecialedition/mods/198). 

 

3) Also under the above link, download the "CBBE SMP Config" under the optional files to get the .xml files that enable the physics on the body.

 

4) A compatible skeleton

 

This is all that is required for SMP to work, at least in Skyrim.  For a more detailed, technical, although incomplete explanation of what is in the .xml files and how SMP works, this pdf is also available: https://www.loverslab.com/applications/core/interface/file/attachment.php?id=581678

 

EDIT: Another in-depth discussion of the .xml files: https://forums.nexusmods.com/index.php?/topic/3800385-a-guide-to-hdt-smp-usersmodders/

 

 

Now, maybe this is all impossible to port over from Skyrim.  Maybe I misunderstood and this doesn't actually solve any problems; I must admit that I am absolutely no expert in modeling or programming, and have little familiarity with the technical underpinnings of physics engines, so I don't know for sure.  But I saw something that, with my limited knowledge, seemed like a workaround for Fallout physics, and I didn't see any discussion of SMP physics around here, so I figured I'd just bring some awareness and perhaps start a discussion on feasibility.

[Andy14]

Small correction:
Even HDT SMP moves bones.

The main difference to HDT PE is that the shapes are created in real time by the SMP itself (based on the skin).
In HDT PE, the shapes are defined beforehand.

 

The limit is not the bones in the skeleton, but the number of bones with which a vertex can be skinned.

Max. 4 bones per vertex - theoretical.

[Mister X]

Basically, theoretically and without real knowledge of implementing something into existing code: Skyrim doesn't have any physics enabled for the bodies whatsoever, neither are there many physically rendered objects.

 

FO4 has extended both, there are more physical objects in the world AND physics is enabled for hair and clothing of characters. Shouldn't it be possible to just hook upon this existing physics framework for the clothing and extend it to certain body parts? This way, nothing new would be needed.

[Guest]

So far there is no real solution for Fo4 body physics.

All the options available are workarounds that perform very badly IMO.

One can only hope for a true crack of the engine physics system.

[dup3w4sh1ngt0n]

It doesn't add physics, it just adds more bones that have to be animated. The "physics" are produced in-program and baked into the animation, so they aren't true, havok-based physics like in Skyrim.