When it is a NSString, do copy in @property

e.g.

@property (copy) NSString *info;

Create NSIndexPath with this Idiom

[NSIndexPath indexPathForRow: inSection:]

http://en.wikipedia.org/wiki/Ambient_occlusion

Chang Chü-cheng (張居正)

Alternative spelling: Zhang Juzheng

Wikipedia link:

http://en.wikipedia.org/wiki/Zhang_Juzheng

Concepts

• Sphere and complex space

• a line in a 1 dim space is a circle; a line in a 1 dim complex space is a sphere

• Riemann Sphere and Space