// no RTL boundary at paragraph start
if (pos == 0)
return false;
-
+
+ // if the metrics have not been calculated, then we are not
+ // on screen and can safely ignore issues about boundaries.
+ if (!contains(pit))
+ return false;
+
ParagraphMetrics & pm = par_metrics_[pit];
// no RTL boundary in empty paragraph
if (pm.rows().empty())