Adding updates

vtkm/Particle.h

@@ -100,6 +100,7 @@ public:
     , Time(time)
   {
     this->Direction = 1;
+    this->DirChanged = false;
   }
 
   VTKM_EXEC_CONT
@@ -108,6 +109,7 @@ public:
     , ID(p.ID)
     , NumSteps(p.NumSteps)
     , Direction(p.Direction)
+    , DirChanged(p.DirChanged)
     , Status(p.Status)
     , Time(p.Time)
   {
@@ -149,6 +151,7 @@ public:
   vtkm::Id ID = -1;
   vtkm::Id NumSteps = 0;
   vtkm::Id Direction = 1;
+  bool DirChanged = 0;
   vtkm::ParticleStatus Status;
   vtkm::FloatDefault Time = 0;
 };

vtkm/worklet/particleadvection/Particles.h

@@ -62,6 +62,7 @@ public:
     newParticle.Pos = pt;
     newParticle.Time = time;
     newParticle.NumSteps++;
+    newParticle.DirChanged = false;
     this->Particles.Set(idx, newParticle);
   }
 

vtkm/worklet/particleadvection/Termination.h

@@ -36,17 +36,19 @@ public:
     /// -- Check if the particle is out of spatial boundaries
     /// -- Check if the particle has reached the maximum number of steps
     /// -- Check if the particle is in a zero velocity region
-    auto& status = particle.Status;
+    auto& status  = particle.Status;
+    auto& changed = particle.DirChanged;
     if(particle.NumSteps == this->MaxSteps)
     {
       status.SetTerminate();
     }
-    if(this->ReverseDirection && (status.CheckSpatialBounds() || status.CheckTemporalBounds()))
+    if(!changed && this->ReverseDirection && (status.CheckSpatialBounds() || status.CheckTemporalBounds()))
     {
       status.SetOk();
       status.ClearSpatialBounds();
       status.ClearTemporalBounds();
       particle.Direction *= -1;
+      particle.DirChanged = true;
     }
     bool terminate =  status.CheckOk()
                       && !status.CheckTerminate()