I

Hello Mathias,It seems to me that you came across the VTPChildPoint structure which was discussed in this forum. It is a structure not documented in the MS SDK docs. Please do a search with the keywords VTP and Child. Regards, Luis

YES ! Thanks so much, Luis. That is exactly it and it also explains that reserved = 3 anomaly.This forum rocks, I guess I should stop by here more often.

Hi Mathias.The latest copy of the BGLC macros for VTP and LWM terrain data are here:http://www.flatface.net/~rhumba/downloads/TDFMacros.zipYou can study the structure of the different data commads by looking at the macros.Also, a version of BGLC containing the new FS9 commands are here:http://www.flatface.net/~rhumba/downloads/BGLC_9_Source.zipDick

Thanks Dick, that helped me find some more discrepancies.Unfortunately I still run into one issue for which I have not found documentation.That is the reserved value in VTPPolyMethod2 (2 bits) being set to 1, 2 or 3. It must have some meaning cause my chugger goes out of sync after that. It only happens in a few files though (NAMWsceneryHL916190.bgl for example).Edit: correction ... I think there is just something wrong with my handling of VTPPolyMethod2Ex Matthias

Ok, I missed the part where VTPPolyMethod2Ex and VTPPolyMethod1Ex have changed to 16 bit values. It's getting through now with no more problems. Thanks again for all the help.Matthias