blender: make progress report work consistent

gds/library.py

@@ -31,7 +31,19 @@ class Library(object):
         
         return (coord[0] * fact, coord[1] * fact)
 
-    def link_refs(self, progress_callback=None):
+    def link_refs(self, root, progress_callback=None):
+        for ref in root.references:
+            if isinstance(ref.structure, str):
+                try:
+                    element.structure = self.structures[ref.structure]
+                except KeyError:
+                    err = LinkError("dangeling sref (structure {} is not defined in library)".format(ref.structure))
+                    err.element = root
+                    raise err
+            
+        return root
+
+    def link_all_refs(self, progress_callback=None):
         class Progress(ProgressGetter):
             total   = 0
             current = 0