Contains area 3D data, including:

• Terrain geometry
• Water geometry
• Grass
• Textures
• If the file is a TRN file:
  • Walkmesh geometry, identical to terrain geometry
• If the file is a baked TRX file:
  
  • Walkmesh geometry, modified by placeable walkmeshes and walkmesh cutters
  • Pathfinding pre-calculated data

File format

The TRN file format is quite similar to MDB format.

Source: https://neverwintervault.org/project/nwn2/other/trn-fileformat

Header struct (12 bytes)

PacketKeyTable struct (8 bytes)

Packet struct (variable length)

Each packet contains different data depending on their type