Index: /trunk/Mars/mgeom/MGeomPix.h
===================================================================
--- /trunk/Mars/mgeom/MGeomPix.h	(revision 9870)
+++ /trunk/Mars/mgeom/MGeomPix.h	(revision 9871)
@@ -26,6 +26,13 @@
 
 public:
+    // Helper to calculate hexagonal geometry
+    enum { kDirCenter, kDirNE, kDirN, kDirNW, kDirSW, kDirS, kDirSE };
+
+    static Double_t CalcXY(Int_t dir, Int_t ring, Int_t i, Double_t &x, Double_t &y);
+
+    // MGeomPix
     MGeomPix(Float_t x=0, Float_t y=0, Float_t d=1, UInt_t s=0, UInt_t aidx=0);
 
+    // TObject
     void Copy(TObject &obj) const
     {
@@ -38,4 +45,7 @@
     }
 
+    void Print(Option_t *opt=NULL) const;
+
+    // Setter
     void SetD(Float_t d=1) { fD=d; fA=d*d*gsSin60; }
     void SetPhi(Double_t phi=0);
@@ -48,8 +58,7 @@
     Float_t GetDy() const { return fD*gsSin60; } // Distance of two rows in y-direction (without rotation)
 
+    // Helper
     Bool_t  IsInside(Float_t px, Float_t py) const;
     void    PaintPrimitive(const TAttLine &line, const TAttFill &fill, Double_t scalexy=1, Double_t scaled=1) const;
-
-    void Print(Option_t *opt=NULL) const;
 
     ClassDef(MGeomPix, 5) // Geometry class describing the geometry of one pixel