Sorry to return your attention to this aging thread!
I am knee deep in IF and I have a been attempting to divine what each of the different node attributes represent such as bpd (block progression dimension?), etc.
It would be really good to have a definitive description of the meaning and function of each of the attribute (and nodes) in an IF document. I have been searching diligently however I have failed to find any document that completely satisfies this requirement.
Would be possible for you provide me with a link to a thorough documentation of the IF format or, if not, perhaps you might be able to provide an explanation of the attributes important for reading the dimension of a given block from an IF document (I think position is bpd, ipd, .. but ipda? and
bpda?) and what are the units (millipoints?).