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How to scale Softbody and other questions
#1
Triste 
Hello,
We recently purchased the Obi Softbody plugin and we are strugling to make it work as we wanted, in our game the user decides the initial scale of the world before playing and everything in that world gets scaled at the start and then you play with that scale.

But the meshes that use softbody doesn't scale as intended, we have read several posts in the unity forums as in here and we got that apparently the way the obi works dynamic scaling is not mathematicaly possible or something like that, the scaling aspect of our game is something we cannot change and we really want to implement softbody physics for some mechanics is there anything we can do to make it work?

Also, we are quite not getting how attachments works as sometimes the mesh bounds get moved outside the camera and the objects don't get rendered, how we can constrain the simulation to stay on the object position but retaining the softbody behaviour? because when we tried to attach some points to the mesh or bones the simulation stop working.
Also, any considerations for the 3d artists, most of our models don't work as expected, in the examples the dragon mesh works flawless with only 3 clicks, but 80% of the models we have tried got mixed results from melting like behvaiour to partial parts of the mesh working as expected.

Thanks!
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#2
(13-03-2020, 01:09 AM)JulioWabisabi Wrote: Hello,
We recently purchased the Obi Softbody plugin and we are strugling to make it work as we wanted, in our game the user decides the initial scale of the world before playing and everything in that world gets scaled at the start and then you play with that scale.

But the meshes that use softbody doesn't scale as intended, we have read several posts in the unity forums as in here and we got that apparently the way the obi works dynamic scaling is not mathematicaly possible or something like that, the scaling aspect of our game is something we cannot change and we really want to implement softbody physics for some mechanics is there anything we can do to make it work?

Also, we are quite not getting how attachments works as sometimes the mesh bounds get moved outside the camera and the objects don't get rendered, how we can constrain the simulation to stay on the object position but retaining the softbody behaviour? because when we tried to attach some points to the mesh or bones the simulation stop working.
Also, any considerations for the 3d artists, most of our models don't work as expected, in the examples the dragon mesh works flawless with only 3 clicks, but 80% of the models we have tried got mixed results from melting like behvaiour to partial parts of the mesh working as expected.

Thanks!

Hi,

- Scaling:
You can just scale the solver component. That will change the scale of the entire simulation. What you can't do though, is scale a single object individually, as mathematically speaking, a deformable object cannot be scaled using a single transform matrix.
See:
http://obi.virtualmethodstudio.com/tutor...olver.html

- Attachments:
Attachments do not affect rendering in any way. If the object is not rendered, it means the bounds of the SkinnedMeshRenderer do not match the mesh. Could you show a video or share a repro project?

Quote:Also, any considerations for the 3d artists, most of our models don't work as expected, in the examples the dragon mesh works flawless with only 3 clicks, but 80% of the models we have tried got mixed results from melting like behvaiour to partial parts of the mesh working as expected.

All models are treated in exactly the same way. However, most generation parameters must be adjusted for each specific model. You can't expect the default generation parameters to work for any mesh.

For instance, if you use the defaults with an object that has vertices very spaced apart, the default cluster radius will fail to generate clusters for most particles, and these will "detach" from the model giving a melting look.  See:
http://obi.virtualmethodstudio.com/tutor...setup.html

Also, the skin radius parameter of the skinner is important. Too low radius values will leave vertices with no skinning. See:
http://obi.virtualmethodstudio.com/tutor...inner.html
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#3
Hi!,

Thanks for the quick response

Quote:- Scaling:
You can just scale the solver component. That will change the scale of the entire simulation. What you can't do though, is scale a single object individually, as mathematically speaking, a deformable object cannot be scaled using a single transform matrix. 
See:
http://obi.virtualmethodstudio.com/tutor...olver.html

For scaling:
  In the softbody configuration the solver needs to be parent of the sofbody, how we can scale the solver without scaling the softbody what is the correct way to do it?
  We have made some tests and so far:
        1) if we scale the solver before play, at runtime the softbody looks wierd but then if we apply the same scale to the softbody everything works as expected.
        2) if we scale the solver during playtime, the softbody looks wierd but then if we apply the same scale to the softbody the softbody looks good but the colisions doesn't work.

Quote:All models are treated in exactly the same way. However, most generation parameters must be adjusted for each specific model. You can't expect the default generation parameters to work for any mesh. 

For instance, if you use the defaults with an object that has vertices very spaced apart, the default cluster radius will fail to generate clusters for most particles, and these will "detach" from the model giving a melting look.  See:
http://obi.virtualmethodstudio.com/tutor...setup.html

Also, the skin radius parameter of the skinner is important. Too low radius values will leave vertices with no skinning. See:
http://obi.virtualmethodstudio.com/tutor...inner.html


For the models:
  Thanks we are looking at the settings with the 3d artists and making test to see how many vertices and what works best.

Quote:- Attachments:

Attachments do not affect rendering in any way. If the object is not rendered, it means the bounds of the SkinnedMeshRenderer do not match the mesh. Could you show a video or share a repro project?


Fo the attachments:
   Yes that was what was happening, if we dont use any particle attachments the skinnedmesh bounds move like crazy and get outside the camera fov, but when using attachments the skinnedmesh bounds get attach to the mesh but the simulation stops working it seems we only need to attach a couple of points to the bones and leave the rest alone? do attachment means those points get anchored to the transform and wont simluate at all?

Kind regards!!
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