The code in this site can be used freely without any charge
The aim of this code is only for education, the author do not
guanratee this code will be safe! So any damage or lose cause 
by this code is totally un-related to the author
Good Luck!



// Dynamic random model
// penetration force will take consideration after the rigid body dynamic have been finished                    
// Here Only consider the disk to disk collision and the disk to boundary collision                    
// consider these collision to be the elastic                    
// disk0 to disk1 the velocity of two disk will change                    
// disk to boundary the velocity of the boundary normal of the disk will reverse                    
// only took consider the two body condistion ?                    
// the three disks collision???                    
//force = force + txPhysicalShpere.CalculateForceFromPenetrationDepth(it.Stiffness, patch.penetrationdepth, patch.normal);