diff --git a/API_GdbGetSurf.cpp b/API_GdbGetSurf.cpp
index dd265d4..d03596a 100644
--- a/API_GdbGetSurf.cpp
+++ b/API_GdbGetSurf.cpp
@@ -84,6 +84,24 @@ __stdcall EgtSurfFrChunkSimpleClassify( int nId1, int nChunk1, int nId2, int nCh
    return ExeSurfFrChunkSimpleClassify( nId1, nChunk1, nId2, nChunk2, dToler) ;
 }
 
+//----------------------------------------------------------------------------
+BOOL
+__stdcall EgtSurfFrChunkCenter( int nId, int nChunk, int nRefId, double ptCen[3], double vtNorm[3])
+{
+  // verifica parametri
+   if ( ptCen == nullptr  ||  vtNorm == nullptr)
+      return FALSE ;
+  // recupero il centro e la normale
+   Point3d ptTmp ;
+   Vector3d vtN ;
+   if ( ! ExeSurfFrChunkCenter( nId, nChunk, nRefId, ptTmp, vtN))
+      return FALSE ;
+  // li assegno
+   VEC_FROM_3D( ptCen, ptTmp)
+   VEC_FROM_3D( vtNorm, vtN)
+   return TRUE ;
+}
+
 //----------------------------------------------------------------------------
 int
 __stdcall EgtExtractSurfFrChunkLoops( int nId, int nChunk, int nDestGrpId, int* pnCount)
diff --git a/EgtInterface.rc b/EgtInterface.rc
index 4e6399e..3fc6dcd 100644
Binary files a/EgtInterface.rc and b/EgtInterface.rc differ