Merge from branch giga

StgSharp.Model/Step/Items/StepEdge.cs

@@ -28,21 +28,22 @@
 //     
 //-----------------------------------------------------------------------
 //-----------------------------------------------------------------------
-using StgSharp.Script;
+using StgSharp.Model.Step;
 
+using StgSharp.Script;
 using StgSharp.Script.Express;
 
 using System.Collections.Generic;
 
-namespace StgSharp.Modeling.Items
+namespace StgSharp.Model.Step
 {
-    public abstract class StepEdge : StepTopologicalRepresentationItem
+    public class StepEdge : StepTopologicalRepresentationItem, IExpConvertableFrom<StepEdge>
     {
 
-        protected StepEdge() : base( string.Empty ) { }
+        protected StepEdge( StepModel model ) : base( model ) { }
 
-        protected StepEdge( string name, StepVertex edgeStart, StepVertex edgeEnd )
-            : base( name )
+        protected StepEdge( StepModel model, StepVertex edgeStart, StepVertex edgeEnd )
+            : base( model )
         {
             EdgeStart = edgeStart;
             EdgeEnd = edgeEnd;
@@ -52,15 +53,16 @@ namespace StgSharp.Modeling.Items
 
         public StepVertex EdgeEnd { get; set; }
 
-        internal override IEnumerable<StepRepresentationItem> GetReferencedItems()
+        public void FromInstance( StepEdge entity )
         {
-            if( EdgeStart != null ) {
-                yield return EdgeStart;
-            }
+            base.FromInstance( entity );
+            EdgeStart = entity.EdgeStart;
+            EdgeEnd = entity.EdgeEnd;
+        }
 
-            if( EdgeEnd != null ) {
-                yield return EdgeEnd;
-            }
+        public override bool IsConvertableTo( string entityName )
+        {
+            return base.IsConvertableTo( entityName ) || entityName == "StepEdge";
         }
 
     }