2D Level of Detail (LOD) algorithm

I have been scouting around the net for an algorithm that enables you to create level of detail (LOD) representations of 2D polygons, but am unable to find ANY decent reference. Maybe I am using the wrong search terms, but all search results are for 3D LOD algorithms, which, I guess, cannot(?) really be applied in 2D.

I am sure that before the onslaught of 3D graphics, many people would have worked on 2D LOD algorithms. Any clues or pointers to where I can get more information? Thanks!