code: public static Xml exportPathData(PathData data)
      {
          Check.notNull(data);
  
          final Xml node = new Xml(NODE_PATH);
          node.writeString(ATT_CATEGORY, data.getName());
          node.writeDouble(ATT_COST, data.getCost());
          node.writeBoolean(ATT_BLOCK, data.isBlocking());
          exportAllowedMovements(node, data.getAllowedMovements());
  
          return node;
      }
docs: Create a path data from its node.
  
  @param data The path data (must not be <code>null</code>).
  @return The path data node.