0026369: Modeling Data - Geom_OffsetSurface direction is wrong for indirect conical...

diff --git a/src/Geom/Geom_OffsetSurface.cxx b/src/Geom/Geom_OffsetSurface.cxx
index c708bb0a9f5a6a5691979ea728dedf1a2161cfa3..049a5c1387b36b6d8ac4281e61e91bdcc4db3594 100644 (file)
--- a/src/Geom/Geom_OffsetSurface.cxx
+++ b/src/Geom/Geom_OffsetSurface.cxx
@@ -1625,16 +1625,33 @@ Handle(Geom_Surface) Geom_OffsetSurface::Surface() const
   {
     Handle(Geom_ConicalSurface) C =
       Handle(Geom_ConicalSurface)::DownCast(Base);
-    Standard_Real Alpha = C->SemiAngle();
-    Standard_Real Radius = C->RefRadius() + offsetValue * Cos(Alpha);
-    gp_Ax3 Axis = C->Position();
-    if ( Radius >= 0.) {
-      gp_Vec Z( Axis.Direction());
-      Z *= - offsetValue * Sin(Alpha);
-      Axis.Translate(Z);
-      Result = new Geom_ConicalSurface(Axis, Alpha, Radius);
+    gp_Ax3 anAxis = C->Position();
+    Standard_Boolean isDirect = anAxis.Direct();
+    Standard_Real anAlpha = C->SemiAngle();
+    Standard_Real aRadius;
+    if (isDirect)
+    {
+      aRadius = C->RefRadius() + offsetValue * Cos (anAlpha);
     }
-    else 
+    else
+    {
+      aRadius = C->RefRadius() - offsetValue * Cos (anAlpha);
+    }
+    if (aRadius >= 0.)
+    {
+      gp_Vec aZ (anAxis.Direction());
+      if (isDirect)
+      {
+        aZ *= -offsetValue * Sin (anAlpha);
+      }
+      else
+      {
+        aZ *=  offsetValue * Sin (anAlpha);
+      }
+      anAxis.Translate (aZ);
+      Result = new Geom_ConicalSurface (anAxis, anAlpha, aRadius);
+    }
+    else
     {
       // surface degeneree      
     }

diff --git a/tests/bugs/moddata_3/bug26369 b/tests/bugs/moddata_3/bug26369
new file mode 100644 (file)
index 0000000..f732aac
--- /dev/null
+++ b/tests/bugs/moddata_3/bug26369
@@ -0,0 +1,29 @@
+puts "============"
+puts "CR26369"
+puts "============"
+puts ""
+###################################################################################
+# Modeling Data - Geom_OffsetSurface direction is wrong for indirect conical surface
+###################################################################################
+
+restore [locate_data_file bug26369_conicsurf.brep] conic_face
+
+mksurface conic_surf conic_face
+offset conic_surf_offset conic_surf 0.05
+mkface conic_face_offset conic_surf_offset
+
+set sprops_s [sprops conic_face_offset]
+set cog_x  -0.00408684
+set cog_y   0.00408684
+set cog_z  -0.03213030
+set cog_tol 0.00000010
+
+regexp {X += +([-0-9.+eE]+)} $sprops_s full res_cog_x
+regexp {Y += +([-0-9.+eE]+)} $sprops_s full res_cog_y
+regexp {Z += +([-0-9.+eE]+)} $sprops_s full res_cog_z
+
+if { ([expr abs($cog_x - $res_cog_x)] > $cog_tol)
+  || ([expr abs($cog_y - $res_cog_y)] > $cog_tol)
+  || ([expr abs($cog_z - $res_cog_z)] > $cog_tol) } {
+  puts "Error: The center of gravity for offset of conical surface is wrong."
+}