diff --git a/EGkPolyLine.h b/EGkPolyLine.h
index 72bc146..1c2caf9 100644
--- a/EGkPolyLine.h
+++ b/EGkPolyLine.h
@@ -134,8 +134,8 @@ typedef std::vector<PolyLine>  POLYLINEVECTOR ;   // vettore di PolyLine
 typedef std::list<PolyLine>    POLYLINELIST ;     // lista di PolyLine
 
 //----------------------------------------------------------------------------
-bool DistPointPolyLine( const Point3d& ptP, const PolyLine& plPoly, double& dDist) ;
-bool IsPointInsidePolyLine( const Point3d& ptP, const PolyLine& plPoly, double dToler) ;
-bool GetPointParamOnPolyLine( const Point3d& ptP, const PolyLine& plPoly, double dToler, double& dPar) ;
-bool ChangePolyLineStart( PolyLine& plPoly, const Point3d& ptNewStart, double dToler) ;
-bool SplitPolyLineAtPoint( const PolyLine& plPoly, const Point3d& ptP, double dToler, PolyLine& plPoly1, PolyLine& plPoly2) ;
+EGK_EXPORT bool DistPointPolyLine( const Point3d& ptP, const PolyLine& plPoly, double& dDist) ;
+EGK_EXPORT bool IsPointInsidePolyLine( const Point3d& ptP, const PolyLine& plPoly, double dToler) ;
+EGK_EXPORT bool GetPointParamOnPolyLine( const Point3d& ptP, const PolyLine& plPoly, double dToler, double& dPar) ;
+EGK_EXPORT bool ChangePolyLineStart( PolyLine& plPoly, const Point3d& ptNewStart, double dToler) ;
+EGK_EXPORT bool SplitPolyLineAtPoint( const PolyLine& plPoly, const Point3d& ptP, double dToler, PolyLine& plPoly1, PolyLine& plPoly2) ;
diff --git a/EGkSurfFlatRegion.h b/EGkSurfFlatRegion.h
index a77c65d..819b471 100644
--- a/EGkSurfFlatRegion.h
+++ b/EGkSurfFlatRegion.h
@@ -15,6 +15,7 @@
 
 #include "/EgtDev/Include/EGkSurf.h"
 #include "/EgtDev/Include/EGkIntersCurves.h"
+#include "/EgtDev/Include/EgkCurveComposite.h"
 #include "/EgtDev/Include/EgtPointerOwner.h"
 
 class ISurfTriMesh ;
@@ -47,6 +48,7 @@ class __declspec( novtable) ISurfFlatRegion : public ISurf
       virtual bool GetChunkCentroid( int nChunk, Point3d& ptCen) const ;
       virtual bool GetCurveClassification( const ICurve& Crv, double dLenMin, CRVCVECTOR& ccClass) const = 0 ;
       virtual int  GetChunkSimpleClassification( int nChunk, const ISurfFlatRegion& Other, int nOthChunk) const ;   // compare only outsides
+      virtual bool GetZigZagInfill( double dSideStep, bool bAllowStepCorrection, bool bInvert, ICRVCOMPOPOVECTOR& vpCrvs) const = 0 ;
 } ;
 
 //-----------------------------------------------------------------------------
diff --git a/EXeExecutor.h b/EXeExecutor.h
index 0c98c35..a0542dd 100644
--- a/EXeExecutor.h
+++ b/EXeExecutor.h
@@ -645,6 +645,8 @@ EXE_EXPORT bool ExeSurfFrTestExternal( int nId1, int nId2, double dMinDist) ;
 EXE_EXPORT int  ExeSurfFrChunkCount( int nId) ;
 EXE_EXPORT int  ExeSurfFrChunkSimpleClassify( int nId1, int nChunk1, int nId2, int nChunk2, double dToler = 0) ;
 EXE_EXPORT int  ExeExtractSurfFrChunkLoops( int nId, int nChunk, int nDestGrpId, int* pnCount) ;
+EXE_EXPORT int  ExeSurfFrGetZigZagInfill( int nId, int nDestGrpId, double dStep, double dAng, bool bStepCorrection, 
+                                          bool bInvert, int* pnCount) ;
 EXE_EXPORT int  ExeSurfTmFacetCount( int nId) ;
 EXE_EXPORT int  ExeSurfTmFacetFromTria( int nId, int nT) ;
 EXE_EXPORT bool ExeSurfTmFacetAdjacencies( int nId, int nFacet, INTMATRIX& vAdj) ;