Question obout materials

[Witek900]

What does exactly NewtonMaterialSetDefaultSoftness and NewtonMaterialSetSurfaceThickness do? On wiki there's nothing about it. What influence softness and thicknes on bodies behavior has?

[Julio Jerez]

softness in hwo fast penetration will be resulved (by penaltry force proportinal to the penetration.)
Thickness is how cloase the collision will be, you can for example set a small sickness value and the shape will not touch.

[tiresius]

I was using softness to help prevent bouncing between two materials and assist in friction for a rolling sphere. Does softness cover that at all or is bounciness purely a product of elasticity?

When I have softness high and elasticity high (0.90) and an object is moving at a decent speed, sometimes I get odd bounces on the edges of coplanar tiles and I attributed this to the collision normals issue with spheres, but perhaps the high softness is letting it have too much penetration which throws off the normals to begin with?

I'll have to play with my settings I may have misunderstood the intended effects of these things.

[Julio Jerez]

softness an deleaticity are very different thing. one is a function of penetration distance and the other is funtion of relative impact velocity
elasticity is the coeficient of restitution according to the equation of impulse. eleaticity is proportional to the relative velocity of impact at a contact.

softness it there to resolve interpenetration only.
Softness is the penetration coneficient that is use to convert teh interpenetration is disatnce to an inpulse veliocity to recove from penetration,
the velocity is then added to the impact velocity.

in future versions of Newton softness will be eliminated all together.
you can leave the softnes coficient to the default and only work with elaticity.

there should not be any edge problems of any kind, can you show me a video of the problem?