12-12-2023, 06:42 AM
Thank you for your response. It helped a lot. I also went through the codes in more detail. I think I have a better idea of what I want help with.
I want to have mathematical/statistical ways to define deformation of a softbody and use that to make decisions. For example, I want to tell the difference between when it bends sideways or twists around. Like, maybe a sideways bend is a 0.5 and a twist is a 0.2, or something like that.
As I understand, Obi Solver tries to confine the softbodies/ropes/clothes to a certain structure so they are not too deformed that they don't resemble the original self but also has some relaxed constraints so that they are not too rigid. There are different sets of constraints that define this confinement. I believe the calculations done behind the scene to confine the softbody to these constraints might hold the values that I am looking for. Is there a mathematical model that you are basing them on? I know 'Position Based Dynamics' algorithm (Müller et al., 2007) is being used for simulation but does PBD also include definitions for all the constraints used in the obi solver or were other mathematical models also used? Can you please recommend the papers or keywords that can I look for understanding these constraints?
Taking an example of bending constraints, let's take a look at the Execute(int i) function of BurstBendConstraintsBatch.cs. The variables bendVector, bend, constraint, compliance and dLambda are used. Are there any standard definition for those? Do they come from any specific model or paper? If they come from specific models then can you please let me know about them otherwise I would love to learn more about them from you.
Finally, do all of these constraints make sense for softbody. I see in documentation that density and chain are used specifically for fluid and rods. Is density properly defined for Obi Fluid asset only and I need to use it or can I play around with this constraint with softbody and see some effects?
I want to have mathematical/statistical ways to define deformation of a softbody and use that to make decisions. For example, I want to tell the difference between when it bends sideways or twists around. Like, maybe a sideways bend is a 0.5 and a twist is a 0.2, or something like that.
As I understand, Obi Solver tries to confine the softbodies/ropes/clothes to a certain structure so they are not too deformed that they don't resemble the original self but also has some relaxed constraints so that they are not too rigid. There are different sets of constraints that define this confinement. I believe the calculations done behind the scene to confine the softbody to these constraints might hold the values that I am looking for. Is there a mathematical model that you are basing them on? I know 'Position Based Dynamics' algorithm (Müller et al., 2007) is being used for simulation but does PBD also include definitions for all the constraints used in the obi solver or were other mathematical models also used? Can you please recommend the papers or keywords that can I look for understanding these constraints?
Taking an example of bending constraints, let's take a look at the Execute(int i) function of BurstBendConstraintsBatch.cs. The variables bendVector, bend, constraint, compliance and dLambda are used. Are there any standard definition for those? Do they come from any specific model or paper? If they come from specific models then can you please let me know about them otherwise I would love to learn more about them from you.
Finally, do all of these constraints make sense for softbody. I see in documentation that density and chain are used specifically for fluid and rods. Is density properly defined for Obi Fluid asset only and I need to use it or can I play around with this constraint with softbody and see some effects?