message: Core: VP Solver now produces virtual force corrsponding to direct minimization.
diff: @@ -107,12 +107,13 @@ namespace Engine
  Vector3 je = s_c_vec;// direction of current
  //////////
  - // TODO: why the 0.5 everywhere??
  - if (parameters.direct_minimization)
  + // Direct minimisation
  + if (parameters.direct_minimization || solver == Solver::VP)
  {
  dtg = parameters.dt * Constants::gamma / Constants::mu_B;
  Vectormath::set_c_cross( dtg, image, force, force_virtual);
  }
  + // Dynamics simulation
  else
  {
  Vectormath::set_c_a( dtg, force, force_virtual);
  @@ -121,7 +122,6 @@ namespace Engine
  // STT
  if (a_j > 0)
  {
  -
  if (parameters.stt_use_gradient)
  {
  auto& geometry = *this->systems[0]->geometry;
  