param pt1
- Previous point
param pt2
- First point
param pt3
- Second point
param pt4
- Next point
param tension
- The tension of the curve, [-1..1] from round to tight.
param continuity
- The continuity of the curve, [-1..1] from box corners to inverted corners.
param bias
- The bias of the curve, [-1..1] from pre-shoot to post-shoot.
returns A function which gives the value on the 2D Kochanek–Bartels curve at t