Support for regional grids in the LayeredData class.

src/layereddata.cpp

@@ -139,20 +139,30 @@ std::pair<const BaseParameters*, MString> LayeredData::Parameters(michlib_intern
   real lon2   = ToGeoDomain(reg.lone, dom);
   real lat1   = reg.latb;
   real lat2   = reg.late;
+  bool global = lone - lonb + 1.5 * lonstep > 360.0;
 
   // Special case when the longitude lies in a small sector between the end and the start
+  if(global)
+  {
    if(lon1 < lonb) lon1 = lone;
    if(lon2 > lone) lon2 = lonb;
-
-  ppar->yb = static_cast<size_t>(Floor((lat1 - latb) / latstep));
-  ppar->ye = static_cast<size_t>(Ceil((lat2 - latb) / latstep));
-  if(ppar->ye > dname.ny - 1) ppar->ye = dname.ny - 1;
-  if(ppar->yb >= ppar->ye) return {nullptr, "Latb must be lesser then late"};
+  }
+  else
+  {
+   if(lon1 < lonb) lon1 = lonb;
+   if(lon2 > lone) lon2 = lone;
+  }
 
   ppar->xb = static_cast<size_t>(Floor((lon1 - lonb) / lonstep));
   ppar->xe = static_cast<size_t>(Ceil((lon2 - lonb) / lonstep));
 
   if(ppar->xb == ppar->xe) return {nullptr, "Lonb must be not equal late"};
+  if(!global && ppar->xb > ppar->xe) return {nullptr, "Lonb must be lesser then lone"};
+
+  ppar->yb = static_cast<size_t>(Floor((lat1 - latb) / latstep));
+  ppar->ye = static_cast<size_t>(Ceil((lat2 - latb) / latstep));
+  if(ppar->ye > dname.ny - 1) ppar->ye = dname.ny - 1;
+  if(ppar->yb >= ppar->ye) return {nullptr, "Latb must be lesser then late"};
 
   if(depth < 0.0 || depth > depths.back())
    ppar->layer = (depth < 0.0) ? 0 : (depths.size() - 1);