DSN export: export keepout zone polygons on each layer they are living

pcbnew/specctra_export.cpp

@@ -1087,13 +1087,25 @@ void SPECCTRA_DB::FromBOARD( BOARD* aBoard )
             else
                 keepout_type = T_keepout;
 
+            // Now, build keepout polygon on each copper layer where the item
+            // keepout is living (keepout zones can live on many copper layers)
+            const int copperCount = aBoard->GetCopperLayerCount();
+
+            for( int layer = 0; layer < copperCount; layer++ )
+            {
+                if( layer == copperCount-1)
+                    layer = B_Cu;
+
+                if( !item->IsOnLayer( PCB_LAYER_ID( layer ) ) )
+                    continue;
+
                 KEEPOUT*   keepout = new KEEPOUT( pcb->structure, keepout_type );
                 pcb->structure->keepouts.push_back( keepout );
 
                 PATH* mainPolygon = new PATH( keepout, T_polygon );
                 keepout->SetShape( mainPolygon );
 
-            mainPolygon->layer_id = layerIds[ kicadLayer2pcb[ item->GetLayer() ] ];
+                mainPolygon->layer_id = layerIds[ kicadLayer2pcb[ layer ] ];
 
                 // Handle the main outlines
                 SHAPE_POLY_SET::ITERATOR iterator;
@@ -1137,6 +1149,7 @@ void SPECCTRA_DB::FromBOARD( BOARD* aBoard )
                 }
             }
         }
+    }
 
     //-----<build the images, components, and netlist>-----------------------
     {