gdk:pango-layout-line-clip-region (line xorigin yorigin ranges)

line -- a pango:layout-line instance
xorigin -- an integer with the x pixel where you intend to draw the layout line with this clip
yorigin -- an integer with the y pixel where you intend to draw the layout line with this clip
ranges -- a list of integer with the byte indexes into the layout, where even members of the list are start indexes and odd elements end indexes

The cairo:region-t instance with the clip region containing the given ranges.

Obtains a clip region which contains the areas where the given ranges of text would be drawn. The xorigin and yorigin arguments are the top left position of the layout. The ranges argument should contain ranges of bytes in the text of the layout. The clip region will include space to the left or right of the line (to the layout bounding box) if you have indexes above or below the indexes contained inside the line. This is to draw the selection all the way to the side of the layout. However, the clip region is in line coordinates, not layout coordinates.

Note that the regions returned correspond to logical extents of the text ranges, not ink extents. So the drawn layout may in fact touch areas out of the clip region. The clip region is mainly useful for highlightling parts of text, such as when text is selected.