Galaxy models:
Interface definition

Bump	A cutoff inverted parabaloid
FixedExp	Elliptical exponential with fixed ratio of major and minor axis
FixedGaussian	Elliptical gaussian with fixed ratio of major and minor axis
Gaussian	Elliptical gaussian with random axis ratio
Point	Delta function
SnapGal	Either a fixed exponential or fixed gaussian with poisson photon distribution

Shear models:
Interface definition

Box	Rectangular constant biased region within an unbiased plane.
Constant	A constant bias level
Image	Shear map taken from a file, and stretched to given dimensions.
Point	Bias from a point mass