Added calculation and reporting of the bounding box of all nodes in the

mesh to ElmerGrid.  If the bounds are greater than 50 (meters) then an
informative notice is output to console.  The purpose is to inform new
users that converting from millimeters to meters may be needed.

elmergrid/src/egmesh.c

@@ -10161,3 +10161,51 @@ int MeshTypeStatistics(struct FemType *data,int info)
   return(0);
 }
 
+int BoundingBox(struct FemType *data,int nomesh,int nomeshes,int info)
+{
+  int i;
+  Real xmin, xmax, ymin, ymax, zmin, zmax, sidemax;
+
+  xmin = xmax = data->x[1];
+  ymin = ymax = data->y[1];
+  zmin = zmax = data->z[1];
+
+  for(i=1; i<=data->noknots; i++){
+    xmax = MAX( xmax, data->x[i] );
+    xmin = MIN( xmin, data->x[i] );
+    ymax = MAX( ymax, data->y[i] );
+    ymin = MIN( ymin, data->y[i] );
+    zmax = MAX( zmax, data->z[i] );
+    zmin = MIN( zmin, data->z[i] );
+  }
+  sidemax = MAX(xmax-xmin,ymax-ymin);
+  sidemax = MAX(sidemax,zmax-zmin);
+
+  if(nomeshes > 1)  {
+    printf("Bounding box of all nodes in mesh[%d] of [%d] meshes:\n",nomesh,nomeshes);
+  }
+  else  {
+    printf("Bounding box of all nodes in mesh:\n");
+  }
+
+  printf("X:[%g,%g] ",xmin,xmax);
+  printf("Y:[%g,%g] ",ymin,ymax);
+  printf("Z:[%g,%g]\n",zmin,zmax);
+
+  if(sidemax > 49.9)  {
+    printf("\nNotice: the longest bounding box side length of [%g] is greater than 50.\n",sidemax);
+    printf("ElmerGUI includes a library of material properties, defined in SI units.  If using ElmerGUI, \n");
+    printf("then the geometry is expected to have meters as length.  Geometry that exceeds 50 meters \n");
+    printf("in length or width or height may not be intended.  Many Geometry generators assume \n");
+    printf("millimeters as the basic unit of length.  Scaling the geometry from millimeters to meters \n");
+    printf("may be the desired action.  For more help, search the Elmer users forum for posts \n");
+    printf("about SI units, or for posts about Coordinate Scaling.\n");
+    printf("Scaling can be accomplished in at least three ways, as follows:\n");
+    printf(" 1. Define the original geometry in meters, not millimeters.\n");
+    printf(" 2. Call ElmerGrid with -scale 0.001 0.001 0.001 as an option.\n");
+    printf(" 3. Add Coordinate Scaling = 0.001 to the simulation section of the sif file.\n");
+    printf("If using Elmer to analyze large geometry, such as a glacier, then ignore this notice.\n\n");
+  }
+
+  return(0);
+}

elmergrid/src/egmesh.h

@@ -112,3 +112,4 @@ int DestroyDualGraph(struct FemType *data,int info);
 int CreateInverseTopology(struct FemType *data,int info);
 int DestroyInverseTopology(struct FemType *data,int info);
 int MeshTypeStatistics(struct FemType *data,int info);
+int BoundingBox(struct FemType *data,int nomesh,int nomeshes,int info);

elmergrid/src/fempre.c

@@ -780,7 +780,9 @@ int main(int argc, char *argv[])
     for(k=0;k<nomeshes;k++) 
       SaveSizeInfo(&data[k],boundaries[k],eg.infofile,info);
   }
-
+
+  if(info) for(k=0;k<nomeshes;k++)
+    BoundingBox(&data[k],k,nomeshes,info);
 
   if(eg.nosave) {
     Goodbye();