/** Two particles
*/
void test_2particles( Real stiffness, Real dampingRatio, Real restLength,
Vec3 x0, Vec3 v0,
Vec3 x1, Vec3 v1,
Vec3 f0)
{
// set position and velocity vectors, using DataTypes::set to cope with tests in dimension 2
VecCoord x(2);
DataTypes::set( x[0], x0[0],x0[1],x0[2]);
DataTypes::set( x[1], x1[0],x1[1],x1[2]);
VecDeriv v(2);
DataTypes::set( v[0], v0[0],v0[1],v0[2]);
DataTypes::set( v[1], v1[0],v1[1],v1[2]);
VecDeriv f(2);
DataTypes::set( f[0], f0[0], f0[1], f0[2]);
DataTypes::set( f[1], -f0[0],-f0[1],-f0[2]);
// randomly rotate and translate the scene
/// @todo functions to apply the transform to VecCoord and VecDeriv
RigidTransform<DataTypes> transform;
transform.randomize(1.1);
transform.projectPoint( x[0]);
transform.projectVector(v[0]);
transform.projectPoint( x[1]);
transform.projectVector(v[1]);
transform.projectVector(f[0]);
transform.projectVector(f[1]);
// tune the force field
this->force->addSpring(0,1,stiffness,dampingRatio,restLength);
// cout<<"test_2particles, x = " << x << endl;
// cout<<" v = " << v << endl;
// cout<<" f = " << f << endl;
// and run the test
this->run_test( x, v, f );
}
