diff --git a/EGkCurve.h b/EGkCurve.h
index 53a3e3f..d1f815e 100644
--- a/EGkCurve.h
+++ b/EGkCurve.h
@@ -29,6 +29,7 @@ class __declspec( novtable) ICurve : public IGeoObj
                     PP_MID = 2,        // punto appartenente all'interno della curva
                     PP_END = 3} ;      // punto coincidente con la fine
       enum ApprLineType { APL_STD = 0,              // approssimazione standard
+                          APL_SPECIAL = 10,         // come STD, per composite conserva estremi di curve componenti
                           APL_LEFT = 1,             // linee sempre a sinistra
                           APL_LEFT_CONVEX = 11,     // linee sempre a sinistra convesse
                           APL_RIGHT = 2,            // linee sempre a destra
diff --git a/EInAPI.h b/EInAPI.h
index 8efa082..4660e83 100644
--- a/EInAPI.h
+++ b/EInAPI.h
@@ -433,6 +433,7 @@ EIN_EXPORT BOOL __stdcall EgtArcNormVersor( int nId, int nRefId, double vtNorm[3
 EIN_EXPORT BOOL __stdcall EgtCurveCompoCenter( int nId, int nSimpCrv, int nRefId, double ptCen[3]) ;
 EIN_EXPORT BOOL __stdcall EgtSurfFrNormVersor( int nId, int nRefId, double vtNorm[3]) ;
 EIN_EXPORT int  __stdcall EgtSurfFrChunkCount( int nId) ;
+EIN_EXPORT int  __stdcall EgtSurfFrChunkSimpleClassify( int nId1, int nChunk1, int nId2, int nChunk2) ;
 EIN_EXPORT int  __stdcall EgtSurfTmFacetCount( int nId) ;
 EIN_EXPORT int  __stdcall EgtSurfTmFacetFromTria( int nId, int nT) ;
 EIN_EXPORT BOOL __stdcall EgtSurfTmFacetNearestEndPoint( int nId, int nFacet, const double ptNear[3], int nRefId,
diff --git a/EXeConst.h b/EXeConst.h
index c78cfe3..be0eeb4 100644
--- a/EXeConst.h
+++ b/EXeConst.h
@@ -45,6 +45,7 @@ enum InterpType{ ITT_ARCS = 0,              // stima tg Akima, curve risultanti
 
 //----------------- Costanti tipo di approssimazione di curve ------------------
 enum ApprType{ APP_LINES = 0,                // come ICurve::APL_STD
+               APP_SPECIAL_LINES = 10,       // come ICurve::APL_SPECIAL
                APP_LEFT_LINES = 1,           // come ICurve::APL_LEFT
                APP_LEFT_CONVEX_LINES = 11,   // come ICurve::APL_LEFT_CONVEX
                APP_RIGHT_LINES = 2,          // come ICurve::APL_RIGHT