nvx/CleanroomGenerator — pull request #1 by hwei (2011-11-03 18:13:08+00:00)
Title: Add Grid Populator 

Can generate grid on surface of ground like this: http://i.imgur.com/UHdja.png
In this example, generator id is "30,stone,20,dirt,1,grass;6,sandstone,3,sand,2,cobblestone,1,gravel".
The "6,sandstone,3,sand,2,cobblestone,1,gravel" controls the grid, which means
divides world into regions (32*32 chunks) with 12-width sandstone lines,
then divides them with 6-width sand lines,
then divides them with 4-width cobblestone lines,
then divides them with 2-width gravel lines.