Move the (light) ball around to light the pillars from various angles and distances. This is a simpler implementation of dynamic lighting than used in the isometric game. It handle shadows and arbitrary angles.
It does not handle shadows that cut light from half of the side of a tile. Either the entire side of a tile is lit, or it is not. Higher precision can be achieved by using smaller tiles.
This simple test was put together using the Image API and about 30 code blocks.