a #GtkTextIter
margin as a [0.0,0.5) fraction of screen size
whether to use alignment arguments (if %FALSE, just get the mark onscreen)
horizontal alignment of mark within visible area
vertical alignment of mark within visible area
Return: %TRUE if scrolling occurred
Scrolls @text_view so that @iter is on the screen in the position indicated by @xalign and @yalign. An alignment of 0.0 indicates left or top, 1.0 indicates right or bottom, 0.5 means center. If @use_align is %FALSE, the text scrolls the minimal distance to get the mark onscreen, possibly not scrolling at all. The effective screen for purposes of this function is reduced by a margin of size @within_margin.
Note that this function uses the currently-computed height of the lines in the text buffer. Line heights are computed in an idle handler; so this function may not have the desired effect if it’s called before the height computations. To avoid oddness, consider using gtk_text_view_scroll_to_mark() which saves a point to be scrolled to after line validation.