cardinal(pt1: Vec2, m1: Vec2, m2: Vec2, pt2: Vec2, tension: number): Vec2
A second order function returning an evaluator for the given 2D Cardinal curve
param
pt1- Previous point
param
m1- First point
param
m2- Second point
param
pt2- Next point
param
tensionThe tension of the curve, [0..1] from round to tight.
returns
A function which gives the value on the 2D Cardinal curve at t