- improved the FlatCAMGerber.isolate() function to work for geometry in the form of list and also in case that the elements of the list are LinearRings (like when doing the Exterior Isolation)

- in NCC Tool made sure that at each run the old objects are deleted

flatcamTools/ToolNonCopperClear.py

@@ -332,6 +332,12 @@ class NonCopperClear(FlatCAMTool, Gerber):
         FlatCAMTool.run(self)
         self.set_tool_ui()
 
+        # reset those objects on a new run
+        self.ncc_obj = None
+        self.bound_obj = None
+        self.obj_name = ''
+        self.bound_obj_name = ''
+
         self.build_ui()
         self.app.ui.notebook.setTabText(2, _("NCC Tool"))
 
@@ -692,6 +698,8 @@ class NonCopperClear(FlatCAMTool, Gerber):
         self.build_ui()
 
     def on_ncc(self):
+        self.bound_obj = None
+        self.ncc_obj = None
 
         try:
             over = float(self.ncc_overlap_entry.get_value())