revealRect
Brings the region rect names of the pane's content into view - in the content's own coordinates, where its top left corner is the origin, whatever the pane is currently scrolled to - and returns whether it was reached.
Revealing is a gesture rather than a declaration: it scrolls where it is called and leaves nothing behind, so no later pass scrolls back and where the user scrolls afterwards stands. Wherever it lands is reported back through x and y, like the user's own scrolling.
false means nothing was revealed: no pane renders this state, or the pane holds no content to scroll. true means the pane was asked to show that region, which scrolls it as far as the content reaches: a region larger than the viewport is shown from its leading edge, and one already in view leaves the pane where it stands.
Return
whether the pane was asked to show the region.
Parameters
the region asked for, read during the call and neither kept nor modified.