[R] cp2tform equivalent

[George Macaulay Shaw]

I'm a new R user and am looking for an R equivalent to the Matlab 'cp2tform' function (see: http://www.mathworks.com/help/toolbox/images/ref/cp2tform.html). 

cp2tform accepts pairs of 2D control points and produces a least-squares optimized spatial transformation from one set of points to the other. Specifically, I'm looking to produce the coefficients of a 3rd order polynomial transformation. 

I'm familiar with the mathematics involved, but am very new to R. If this functionality isn't implemented in R directly, a brief outline of the R functions that I'd use to implement it myself would be helpful. 

Thanks!