[FieldTrip] Question concerning ft_headmodel_bem_openmeeg

[Paul Czienskowski]

Dear all,

I want to create headmodels with the ft_headmodel_bem_openmeeg function, 
and - for I formerly used the ft_prepare_bemmodel function - decided to 
delve into the new function first, to see how it works. Anyway, I 
stumbled upon something that puzzled me a bit. In line 96 to 106, the 
boundaries are rearranged to be inside first, which to my understanding 
means, that the first boundary in the array of boundaries will be the 
innermost one (i.e. the brain in my case) and the last boundary will be 
the outermost one (i.e. skin). Everything's fine hitherto. But from line 
108 on, things become quite odd. Line 108 and 109 define the first 
compartment to be the skin and the last to be the source compartment. 
This is cross-checked again in line 127 to 129. To my understanding this 
is a contradiction and I would appreciate, if anybody could tell me if I 
got something completely wrong, or if the function does odd things. If 
the function is correct, there should at least be a comment explaining 
why this contradiction makes sense anyway.

Best regards,
Paul