computeB method
Computes the right hand side of the SPOOK equation
Implementation
@override
double computeB(double h){
final b = this.b;
final ri = this.ri;
final rj = this.rj;
final rixt = _frictionEquationComputeBTemp1;
final rjxt = _frictionEquationComputeBTemp2;
final t = this.t;
// Caluclate cross products
ri.cross(t, rixt);
rj.cross(t, rjxt);
// G = [-t -rixt t rjxt]
// And remember, this is a pure velocity constraint, g is always zero!
final ga = jacobianElementA;
final gb = jacobianElementB;
t.negate(ga.spatial);
rixt.negate(ga.rotational);
gb.spatial.copy(t);
gb.rotational.copy(rjxt);
final gw = computeGW();
final giMf = computeGiMf();
final B = -gw * b - h * giMf;
return B;
}