{This puckered texture is used to provide a bumpy look.
A1 is the degree of puckeredness puck_dx, puck_dy, puck_dz are the 
perturbation variables in the x, y and z directions.}


puck_dx = A1 * noise3a(Px, Py, Pz);
puck_dy = A1 * noise3b(Px, Py, Pz);
puck_dz = A1 * noise3c(Px, Py, Pz);
