NWN Binary Model Files Basics
The binary format of the model files contains 3 main sections, the header, the model data and the vertex or raw data.
The header is a only twelve bytes long. It provides us with the offset and size of the raw data, and a 32 bit value of 0. The value of 0 is important since it can be used to tell the difference between an ASCII model file and a binary one. The chances of an ASCII model file starting with 4 bytes of 0 is somewhere between zero and none.
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[Edit - Shortened as reformatted ver available below)