Tile engine

[LukasT.dev@gmail.com]

Hi, 

I would like to ask if we have tile row hinting?
Described here http://git.gnome.org/cgit/gimp/tree/NEWS?h=gimp-1-2 as 

"The image compositing has been speed up by                          
implementing hints to the tile structure.
That way the render-engine knows for example
if a row is totally transparent and can skip
the calculation."

Dimitry, do you know about any papers/articles describing the tile engine?