Infill type
Infill type for a given brush. IceSL is packed
with four options listed bellow. It is possible
to add a custom infill by writing its specifi-
cation (see 'README.md' file in 'icesl-infillers'
folder):

-Automatic: Tetrahedral infills (best for the
majority of situations).

-Progressive: Changes to infill percentage
produce smooth variations on the output.

-Cubic: Cubic infills with no smoothing
of infill percentage variations.

-Polyfoam: Sponge-like structure infill. See other
settings below for more control of the output.

-Phasor: Procedural phasor noise infill; highly
deformable structure. See other settings below
for more control of the output.