Collision check and particlePosition -> random

- A new class is added for simple collision check
- position particles in utility is upgraded
- morton sorting is not active yet for particlesPhasicFlow

src/Particles/Insertion/collisionCheck/collisionCheck.cpp

@@ -0,0 +1,91 @@
+#include "collisionCheck.hpp"
+
+bool
+pFlow::collisionCheck::build()
+{
+	fill(head_, static_cast<uint32>(-1));
+	fill(next_, static_cast<uint32>(-1));
+
+	for (auto i = 0uL; i < position_.size(); i++)
+	{
+		if(!searchBox_.isInside(position_[i]))
+        {
+            fatalErrorInFunction<<
+            "Point "<< position_[i]<< "is not in search box"<<endl;
+        }
+
+        const auto ind                   = pointIndex(position_[i]);
+		next_[i]                         = head_(ind.x(), ind.y(), ind.z());
+		head_(ind.x(), ind.y(), ind.z()) = static_cast<uint32>(i);
+	}
+
+    return true;
+}
+
+pFlow::collisionCheck::collisionCheck(
+  box                 sBox,
+  real                dx,
+  const realx3Vector& pos,
+  const realVector&   diam
+)
+  : searchBox_(sBox),
+    dx_(dx),
+    nCells_((sBox.maxPoint() - sBox.minPoint()) / dx + realx3(1.0)),
+    position_(pos),
+    diameters_(diam),
+    next_("next", pos.size()),
+    head_("head", nCells_.x(), nCells_.y(), nCells_.z())
+{
+	if(!build())
+    {
+        fatalExit;
+    }
+}
+
+bool
+pFlow::collisionCheck::checkPoint(const realx3& p, const real d) const
+{
+    
+    if(!searchBox_.isInside(p)) return false;
+
+    const auto ind = pointIndex(p);
+    
+    uint32 n = head_(ind.x(), ind.y(), ind.z());
+    while( n != -1)
+    {
+        if( (position_[n]-p).length() - 0.5*(diameters_[n]+d )<0.0 )
+        {
+            return false;
+        }
+        n = next_[n];
+    }
+	return true;
+}
+
+bool
+pFlow::collisionCheck::mapLastAddedParticle()
+{
+    size_t n = position_.size()-1;
+    if( next_.size() != n )
+    {
+        fatalErrorInFunction<<
+        "size mismatch of next and position"<<endl;
+        return false;
+    }
+    next_.push_back(-1);
+    const auto& p = position_[n];
+
+    if(!searchBox_.isInside(p))
+    {
+        fatalErrorInFunction<< 
+        "Point "<< p <<" is not inside the search box"<<endl;
+        return false;
+    }
+
+    const auto ind = pointIndex(p);
+
+    next_[n]       = head_(ind.x(), ind.y(), ind.z());
+    head_(ind.x(), ind.y(), ind.z()) = static_cast<uint32>(n);
+
+	return true;
+}