No, actually, I realized what caused the shadow to look weird. The shadow of the small tower takes all "four sides" into account, but it is emitted from only one side, causing it to look strange, and helping the illusion of a malplaced light source.

And thanks for your feedback all. Much appreciated, except for your random remarks, Randuin. That's just low.

"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram