diff --git a/EGkColor.h b/EGkColor.h
index fab601d..58042fb 100644
--- a/EGkColor.h
+++ b/EGkColor.h
@@ -26,6 +26,7 @@
 //-----------------------------------------------------------------------------
 const int MAX_RGB = 255 ;
 const int MAX_ALPHA = 100 ;
+const int ALPHA_LIM = 90 ;                       // valore di opacità equivalente al 100%
 const float INV_MAX_RGB = 1 / float( MAX_RGB) ;
 const float INV_MAX_ALPHA = 1 / float( MAX_ALPHA) ;
 
diff --git a/EGkIntersLinePlane.h b/EGkIntersLinePlane.h
new file mode 100644
index 0000000..ecae8e0
--- /dev/null
+++ b/EGkIntersLinePlane.h
@@ -0,0 +1,39 @@
+//----------------------------------------------------------------------------
+//  EgalTech 2015-2015
+//----------------------------------------------------------------------------
+// File : EGkIntersLinePlane.h      Data : 18.02.15         Versione : 1.6b7
+// Contenuto : Dichiarazione della classe intersezione linea/piano.
+//
+//
+//
+// Modifiche : 18.02.15 DS Creazione modulo.
+//
+//
+//----------------------------------------------------------------------------
+
+#pragma once
+
+#include "/EgtDev/Include/EGkPlane3d.h"
+
+//----------------------- Macro per import/export ----------------------------
+#undef EGK_EXPORT
+#if defined( I_AM_EGK)            // da definirsi solo nella DLL
+   #define EGK_EXPORT __declspec( dllexport)
+#else
+   #define EGK_EXPORT __declspec( dllimport)
+#endif
+
+//-----------------------------------------------------------------------------
+EGK_EXPORT int IntersLinePlane( const Point3d& ptL1, const Point3d& ptL2, const Plane3d& plPlane,
+                                Point3d& ptInt) ;
+EGK_EXPORT int IntersLinePlane( const Point3d& ptL, const Vector3d& vtL, double dLen, const Plane3d& plPlane,
+                                Point3d& ptInt) ;
+
+//-----------------------------------------------------------------------------
+// Tipo di intersezione linea-piano
+const int ILPT_NO = 0 ;          // non c'è intersezione
+const int ILPT_INPLANE = 1 ;     // la linea giace nel piano
+const int ILPT_START = 2 ;       // l'intersezione è il punto iniziale
+const int ILPT_END = 3 ;         // l'intersezione è il punto finale
+const int ILPT_YES = 4 ;         // intersezione con attraversamento
+  
\ No newline at end of file
diff --git a/EGkIntersLineTria.h b/EGkIntersLineTria.h
new file mode 100644
index 0000000..2356d68
--- /dev/null
+++ b/EGkIntersLineTria.h
@@ -0,0 +1,38 @@
+//----------------------------------------------------------------------------
+//  EgalTech 2015-2015
+//----------------------------------------------------------------------------
+// File : EGkIntersLinePlane.h      Data : 18.02.15         Versione : 1.6b7
+// Contenuto : Dichiarazione della classe intersezione linea/piano.
+//
+//
+//
+// Modifiche : 18.02.15 DS Creazione modulo.
+//
+//
+//----------------------------------------------------------------------------
+
+#pragma once
+
+#include "/EgtDev/Include/EGkTriangle3d.h"
+
+//----------------------- Macro per import/export ----------------------------
+#undef EGK_EXPORT
+#if defined( I_AM_EGK)            // da definirsi solo nella DLL
+   #define EGK_EXPORT __declspec( dllexport)
+#else
+   #define EGK_EXPORT __declspec( dllimport)
+#endif
+
+//-----------------------------------------------------------------------------
+EGK_EXPORT int IntersLineTria( const Point3d& ptL1, const Point3d& ptL2, const Triangle3d& trTria,
+                               Point3d& ptInt) ;
+EGK_EXPORT int IntersLineTria( const Point3d& ptL, const Vector3d& vtL, double dLen, const Triangle3d& trTria,
+                               Point3d& ptInt) ;
+
+//-----------------------------------------------------------------------------
+// Tipo di intersezione linea-triangolo
+enum IntLineTriaType { ILTT_NO = 0,            // non c'è intersezione
+                       ILTT_SEGM = 1,          // una parte di linea appartiene al triangolo
+                       ILTT_VERT = 2,          // intersezione coincide con un vertice
+                       ILTT_EDGE = 3,          // intersezione coincide con interno di un lato
+                       ILTT_IN = 4} ;          // intersezione coincide con interno del triangolo
diff --git a/EGrScene.h b/EGrScene.h
index 657d508..08495f9 100644
--- a/EGrScene.h
+++ b/EGrScene.h
@@ -59,6 +59,7 @@ class IEGrScene
       virtual int  GetFirstSelectedObj( void) = 0 ;
       virtual int  GetNextSelectedObj( void) = 0 ;
       virtual double GetSelectedObjWinZ( int nSel = - 1) = 0 ;
+      virtual double GetSelectedObjMinWinZ( int nSel = - 1) = 0 ;
       virtual bool GetPointFromSelect( int nSelId, const Point3d& ptView, Point3d& ptSel) = 0 ;
       virtual bool Project( const Point3d& ptWorld, Point3d& ptView) = 0 ;
       virtual bool UnProject( const Point3d& ptView, Point3d& ptWorld) = 0 ;
@@ -144,8 +145,9 @@ enum SnapPoint { SP_NONE = 0,
                  SP_END = 3,
                  SP_MID = 4,
                  SP_CENTER = 5,
-                 SP_NEAR = 6,
-                 SP_INTERS = 7,
-                 SP_TANG = 8,
-                 SP_PERP = 9,
-                 SP_MINDIST = 10} ;
\ No newline at end of file
+                 SP_CENTROID = 6,
+                 SP_NEAR = 7,
+                 SP_INTERS = 8,
+                 SP_TANG = 9,
+                 SP_PERP = 10,
+                 SP_MINDIST = 11} ;
\ No newline at end of file
diff --git a/EInAPI.h b/EInAPI.h
index 3808554..4404957 100644
--- a/EInAPI.h
+++ b/EInAPI.h
@@ -291,6 +291,7 @@ EIN_EXPORT BOOL __stdcall EgtStartPoint( int nId, int nRefId, double ptP[3]) ;
 EIN_EXPORT BOOL __stdcall EgtEndPoint( int nId, int nRefId, double ptP[3]) ;
 EIN_EXPORT BOOL __stdcall EgtMidPoint( int nId, int nRefId, double ptP[3]) ;
 EIN_EXPORT BOOL __stdcall EgtCenterPoint( int nId, int nRefId, double ptP[3]) ;
+EIN_EXPORT BOOL __stdcall EgtCentroid( int nId, int nRefId, double ptP[3]) ;
 EIN_EXPORT BOOL __stdcall EgtAtParamPoint( int nId, double dU, int nRefId, double ptP[3]) ;
 EIN_EXPORT BOOL __stdcall EgtNearPoint( int nId, const double ptNear[3], int nRefId, double ptP[3]) ;
 EIN_EXPORT BOOL __stdcall EgtIntersectionPoint( int nId1, int nId2, const double ptNear[3], int nRefId, double ptP[3]) ;
@@ -307,7 +308,9 @@ EIN_EXPORT BOOL __stdcall EgtCurveThickness( int nId, double* pdThick) ;
 EIN_EXPORT BOOL __stdcall EgtGetMinDistPointCurve( const double ptP[3], int nId, double* pdDist) ;
 EIN_EXPORT BOOL __stdcall EgtGetMinDistPntSidePointCurve( const double ptP[3], int nId, double vtN[3],
                                                           double* pdDist, double ptMin[3], int* pnSide) ;
+EIN_EXPORT BOOL __stdcall EgtCurveArcRadius( int nId, double* pdRad) ;
 EIN_EXPORT BOOL __stdcall EgtCurveArcNormVersor( 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 EgtExtTextNormVersor( int nId, int nRefId, double vtNorm[3]) ;
 EIN_EXPORT BOOL __stdcall EgtPointToIdGlob( double ptP[3], int nId) ;
 EIN_EXPORT BOOL __stdcall EgtPointToIdLoc( double ptP[3], int nId) ;
diff --git a/EgkCurve.h b/EgkCurve.h
index bc47911..e54f9b7 100644
--- a/EgkCurve.h
+++ b/EgkCurve.h
@@ -44,6 +44,7 @@ class __declspec( novtable) ICurve : public IGeoObj
       virtual bool GetEndPoint( Point3d& ptEnd) const = 0 ;
       virtual bool GetMidPoint( Point3d& ptMid) const = 0 ;
       virtual bool GetCenterPoint( Point3d& ptCen) const = 0 ;
+      virtual bool GetCentroid( Point3d& ptCen) const = 0 ;
       virtual bool GetStartDir( Vector3d& vtDir) const = 0 ;
       virtual bool GetEndDir( Vector3d& vtDir) const = 0 ;
       virtual bool GetMidDir( Vector3d& vtDir) const = 0 ;
diff --git a/EgkCurveComposite.h b/EgkCurveComposite.h
index 736d872..e49ae97 100644
--- a/EgkCurveComposite.h
+++ b/EgkCurveComposite.h
@@ -30,6 +30,7 @@ class __declspec( novtable) ICurveComposite : public ICurve
       virtual bool PolygonCenterMidSide( int nSides, const Point3d& ptCen, const Point3d& ptMidSide, const Vector3d& vtN) = 0 ;
       virtual bool PolygonSide( int nSides, const Point3d& ptStart, const Point3d& ptEnd, const Vector3d& vtN) = 0 ;
       virtual int  GetCurveNumber( void) const = 0 ;
+      virtual const ICurve* GetCurve( int nCrv) const = 0 ;
       virtual const ICurve* GetFirstCurve( void) const = 0 ;
       virtual const ICurve* GetNextCurve( void) const = 0 ;
       virtual const ICurve* GetLastCurve( void) const = 0 ;
diff --git a/EgkSurfTriMesh.h b/EgkSurfTriMesh.h
index 672ac35..0cf38ff 100644
--- a/EgkSurfTriMesh.h
+++ b/EgkSurfTriMesh.h
@@ -49,12 +49,17 @@ class __declspec( novtable) ISurfTriMesh : public ISurf
       virtual int  GetTriangleSize( void) const = 0 ;
       virtual double GetLinearTolerance( void) = 0 ;
       virtual double GetSmoothAngle( void) = 0 ;
+      virtual bool GetVertex( int nId, Point3d& ptP) const = 0 ;
       virtual int  GetFirstVertex( Point3d& ptP) const = 0 ;
       virtual int  GetNextVertex( int nId, Point3d& ptP) const = 0 ;
+      virtual bool GetTriangle( int nId, int nIdVert[3]) const = 0 ;
       virtual int  GetFirstTriangle( int nIdVert[3]) const = 0 ; 
       virtual int  GetNextTriangle( int nId, int nIdVert[3]) const = 0 ; 
+      virtual bool GetTriangle( int nId, Triangle3d& Tria) const = 0 ;
       virtual int  GetFirstTriangle( Triangle3d& Tria) const = 0 ; 
       virtual int  GetNextTriangle( int nId, Triangle3d& Tria) const = 0 ; 
+      virtual int  GetAllTriaAroundVertex( int nV, INTVECTOR& vT, bool& bCirc) const = 0 ;
+      virtual bool GetVertexSmoothNormal( int nV, int nT, Vector3d& vtN) const = 0 ;
       virtual bool GetTriangleBoundaryEdges( int nId, TriFlags3d& TFlags) const = 0 ;
       virtual bool GetTriangleSmoothNormals( int nId, TriNormals3d& TNrms) const = 0 ;
 } ;