gtk:tree-view-path-at-pos (view x y)

view -- a gtk:tree-view widget
x -- an integer with the x position to be identified (relative to the GDK window)
y -- an integer with the y position to be identified (relative to the GDK window)

path -- a gtk:tree-path instance, or nil
column -- a gtk:tree-view-column object, or nil
xcell -- an integer with the x coordinate relative to the cell
ycell -- an integer with the y coordinate relative to the cell

Finds the path at the point (x,y), relative to the GDK window coordinates. Please see the gtk:tree-view-bin-window function. That is, x and y are relative to an events coordinates. The x and y coordinates must come from an event on the tree view only where the event window from the gdk:event-window function is equal to the GDK window from the gtk:tree-view-bin-window function. It is primarily for things like popup menus.

If the path argument is non-nil, then it will be filled with the gtk:tree-path instance at that point. If the column argument is non-nil, then it will be filled with the column at that point. The xcell and ycell values return the coordinates relative to the cell background, i.e. the background value passed to the gtk:cell-renderer-render function. This function is only meaningful if the tree view is realized. Therefore this function will always return nil if the tree view is not realized or does not have a model.

For converting widget coordinates, e.g. the ones you get from the "query-tooltip" signal, please see the gtk:tree-view-convert-widget-to-bin-window-coords function.