+
+ /* turn permission should always be stricter than page permission
+ and page permission should always be stricter than line permission */
+ line.page_permission_ = min_permission (line.break_permission_,
+ line.page_permission_);
+ line.turn_permission_ = min_permission (line.page_permission_,
+ line.turn_permission_);
+
+ line.extent_ = (extent.is_empty ()
+ || isnan (extent[LEFT])
+ || isnan (extent[RIGHT]))
+ ? Interval (0, 0) : extent;