R package Kohonen - how to plot hexagons instead of circles as in Matlab SOM toolbox?

Question

Is it possible to plot the SOM map (package Kohonen) with hexagons as elementary forms instead of circles? Now the different plottings (count, changes etc.) are plotted as

Answer 1

I don't have sufficient reputation to comment on @NBremer's answer. I have extended the above code to allow visualization of large component planes and u-matrices for output from the R "kohonen" library. Code and worked examples available here:

R SOM Visualization Functions