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+--- Thread: What defines overall attributes of softbodies (/thread-1061.html)
What defines overall attributes of softbodies - aphixe - 09-04-2019
I am not an expert at all in physics. but what defines the attributes, of a softbodie. I know normally outside softbodies, we use rigidbodies to define, mass/weight, etc. what makes the softbodies over all attributes. like how soft something is, can you inflate things like a tire, can you make things more bouncy. only thing that changed most of the charactistics for me was the friction of an object, but that just made it slide or not slide on surface. maybe I need to reread the documents. but some things don't make sense yet.
RE: What defines overall attributes of softbodies - josemendez - 09-04-2019
(09-04-2019, 09:25 AM)aphixe Wrote: I am not an expert at all in physics. but what defines the attributes, of a softbodie. I know normally outside softbodies, we use rigidbodies to define, mass/weight, etc. what makes the softbodies over all attributes. like how soft something is, can you inflate things like a tire, can you make things more bouncy. only thing that changed most of the charactistics for me was the friction of an object, but that just made it slide or not slide on surface. maybe I need to reread the documents. but some things don't make sense yet.
Hi,
Shape matching constraints control most of the behavior of the softbody:
http://obi.virtualmethodstudio.com/tutorials/shapematchingconstraints.html
Note that the exact extent of the effect these parameters have depends of global solver settings (specially substeps and amount of shape matching constraint iterations). All iterative solvers (99% of all solvers used in games, Obi being no exception) can attain more stiffness when letting them run more substeps/iterations.
Bounciness depends on how stiff the softbody is. Stiff softbodies will generally bounce more than less stiff ones, just like in real life. Bouncing objects bounce because they compress upon collision, storing energy. Once they release this energy by decompressing, they bounce off the surface. Rigidbodies approximate this by modifying their velocity upon collision, because they cannot deform (by definition, they're completely rigid).
You can also change per-particle masses, to control overall softbody mass and/or change the center of mass:
http://obi.virtualmethodstudio.com/tutorials/particleediting.html