ENH: use simpler boundBox handling

- use default initialize boundBox instead of invertedBox
- reset() instead of assigning from invertedBox
- extend (three parameter version) and grow method
- inflate(Random) instead of extend + re-assigning

src/parallel/distributed/distributedTriSurfaceMesh/distributedTriSurfaceMesh.C

@@ -950,7 +950,7 @@ Foam::distributedTriSurfaceMesh::findBestProcs
                 // Minimum search distance to find the triangle
                 point near, far;
                 bbs[bbi].calcExtremities(centre, near, far);
-                minDistSqr = min(minDistSqr, magSqr(centre-far));
+                minDistSqr = min(minDistSqr, centre.distSqr(far));
             }
         }
     }
@@ -977,11 +977,11 @@ Foam::distributedTriSurfaceMesh::findBestProcs
                     point near, far;
                     bbs[bbi].calcExtremities(centre, near, far);
 
-                    scalar d2 = magSqr(centre-near);
+                    scalar d2 = centre.distSqr(near);
                     if (d2 < minDistSqr)
                     {
                         minDistSqr = d2;
-                        maxDistSqr = min(radiusSqr, magSqr(centre-far));
+                        maxDistSqr = min(radiusSqr, centre.distSqr(far));
                         minProci = proci;
                     }
                 }
@@ -1748,12 +1748,11 @@ Foam::distributedTriSurfaceMesh::independentlyDistributedBbs
 
 
     // Initialise to inverted box
-    List<List<treeBoundBox>> bbs(Pstream::nProcs());
-    forAll(bbs, proci)
-    {
-        bbs[proci].setSize(1, treeBoundBox(boundBox::invertedBox));
-    }
-
+    List<List<treeBoundBox>> bbs
+    (
+        Pstream::nProcs(),
+        List<treeBoundBox>(1, treeBoundBox::null())
+    );
 
     const globalIndex& triIndexer = globalTris();
 
@@ -3735,7 +3734,7 @@ void Foam::distributedTriSurfaceMesh::findLineAll
     const vectorField smallVec
     (
         ROOTSMALL*dirVec
-      + vector(ROOTVSMALL,ROOTVSMALL,ROOTVSMALL)
+      + vector::uniform(ROOTVSMALL)
     );
 
     // Copy to input and compact any hits

src/parallel/distributed/patchDistMethods/exact/exactPatchDistMethod.C

@@ -52,13 +52,13 @@ Foam::patchDistMethods::exact::patchSurface() const
 
         Random rndGen(0);
 
-        boundBox localBb(mesh_.points(), false);
+        treeBoundBox localBb(mesh_.points());
 
         // Determine mesh bounding boxes:
         List<treeBoundBox> meshBb
         (
             1,
-            treeBoundBox(localBb).extend(rndGen, 1E-3)
+            localBb.extend(rndGen, 1E-3)
         );
 
         // Dummy bounds dictionary