The tySpiral modifier applies a circular deformation to geometry, outward from a central axis. It is similar to 3ds Max’s built-in Twist modifier, except that instead of deforming geometry around an axis in an absolute manner, the strength of the circular effect has a falloff, allowing the deformation to form a spiral pattern.
Amount: the amount, in degrees, of spiral deformation to apply.
Axis X/Y/Z: the local axis of the sub-object gizmo around which to apply the spiral deformation.
Start: the minimum distance from the specified axis a vertex must be in order to undergo deformation.
Invert: inverts the spiral effect, so that vertices within the “start” distance will undergo deformation, rather than vertices further than the “start” distance.
Extrapolate: extrapolates the spiral deformation effect amount, for vertices that are further from the “start” distance to the specified axis than the falloff amount.
Falloff: the maximum distance past the “start” distance from the specified axis to apply the deformation.
Falloff curve: defines the deformation amount from “start” distance to [“start” + falloff] distance from the specified axis.
Accuracy: defines the internal resolution of the falloff curve. Values that are too low can produce geometry artifacts when the spiral amount value is high.