What does the layer structures and the macro structre describe in a LEF file?
Here are a couple of files that may be useful:


400+ page spec: LEF/DEF Language Reference, Cadence, v5.7, Nov 2009
A slide deck referenced by the Wikipedia article on the LEF format. Standard Cell Library/Library Exchange Format (LEF), CMPE 641, via Wayback Machine


I can't find the official source for the LEF file formats, though. The Cadence one above looks like a copy saved as part of a contest through the International Symposium on Physical Design, but probably not entirely legitimately.