rearrangements and comments

nifty_gridder.cc

@@ -552,6 +552,15 @@ template<typename T> class GridderConfig
     T beta;
     vector<T> cfu, cfv;
 
+    complex<T> wscreen(double x, double y, double w, bool adjoint) const
+      {
+      constexpr double pi = 3.141592653589793238462643383279502884197;
+      double n = cos(sqrt(x+y)), xn = 1./n;
+      double phase = 2*pi*w*(n-1);
+      if (adjoint) phase *= -1;
+      return complex<T>(cos(phase)*xn, sin(phase)*xn);
+      }
+
   public:
     GridderConfig(size_t nxdirty, size_t nydirty, double epsilon,
       double pixsize_x, double pixsize_y)
@@ -707,14 +716,6 @@ template<typename T> class GridderConfig
       }
       return tmp;
       }
-    complex<T> wscreen(double x, double y, double w, bool adjoint) const
-      {
-      constexpr double pi = 3.141592653589793238462643383279502884197;
-      double n = cos(sqrt(x+y)), xn = 1./n;
-      double phase = 2*pi*w*(n-1);
-      if (adjoint) phase *= -1;
-      return complex<T>(cos(phase)*xn, sin(phase)*xn);
-      }
     inline void getpix(T u_in, T v_in, T &u, T &v, int &iu0, int &iv0) const
       {
       u=fmodulo(u_in*psx, T(1))*nu,
@@ -745,17 +746,16 @@ template<typename T> class GridderConfig
           {
           double fy = y0+j*psy;
           auto ws = wscreen(fx, fy*fy, w, adjoint);
-          res[ny_dirty*i+j] = dirty[ny_dirty*i+j]*ws;
-          size_t i2 = nx_dirty-i,
-                 j2 = ny_dirty-j;
+          res[ny_dirty*i+j] = dirty[ny_dirty*i+j]*ws; // lower left
+          size_t i2 = nx_dirty-i, j2 = ny_dirty-j;
           if ((i>0)&&(i<i2))
             {
-            res[ny_dirty*i2+j] = dirty[ny_dirty*i2+j]*ws;
+            res[ny_dirty*i2+j] = dirty[ny_dirty*i2+j]*ws; // lower right
             if ((j>0)&&(j<j2))
-              res[ny_dirty*i2+j2] = dirty[ny_dirty*i2+j2]*ws;
+              res[ny_dirty*i2+j2] = dirty[ny_dirty*i2+j2]*ws; // upper right
             }
           if ((j>0)&&(j<j2))
-            res[ny_dirty*i+j2] = dirty[ny_dirty*i+j2]*ws;
+            res[ny_dirty*i+j2] = dirty[ny_dirty*i+j2]*ws; // upper left
           }
         }
 }