Object IDs

Okay, I think I understand the statement of my current problem. In 8.1, Base Node Data included an Object ID. The Property Table was a list of keys and values, each of which was an Object ID, whic I would look up through the list of Object IDs read in.

In 9.5 Base Node Data no longer has the Object ID field. So I have no idea what those keys and values refer to any more…

(Posting this in the moment, haven’t had a chance to look up the property table in the 9.5 spec, and it’s time for me to cook dinner now…)

Updated: Okay, I think I’ve got it. But this is pure conjecture, I haven’t tried coding it up yet. If you look at the graph for the Element Header, 9.5 has added a very mysterious “I32: Texture Coord” field. (It’s “I32: Texture Coord Channel” in the ISO 14306 document.) If you actually read the descriptions of the fields, where the “I32: Texture Coord” should be explained is “I32: Object ID. Object ID is the identifier for this Object.”

So somehow they appear to have made a major typo THE most important field in element. And in the ISO 14306 it’s a slightly different version of the typo. What the heck? Did anyone actually try to implement this specification before making it a standard?

Final Update: I can confirm that the “I32: Texture Coord” field definitely appears to actually be the Object ID. I have this implemented now, and the import is getting a lot further before it falls apart. Alas, the tri-strip storage code seems to have utterly changed since 8.1…

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