catmullRom(pt1: Vec2, m1: Vec2, m2: Vec2, pt2: Vec2): Vec2
A second order function returning an evaluator for the given 2D Catmull-Rom curve
param
pt1- Previous point
param
m1- First point
param
m2- Second point
param
pt2- Next point
returns
A function which gives the value on the 2D Catmull-Rom curve at t