ConstReadonlybid: 1Building id (per-building weather lookup).
Readonlyfacade: 4Walls: style code (+8 = shops), per-wall seed, wall length (0 = no windows), material. Roofs: part, seed, 0, material.
Readonlynormal: 3Flat face normal.
Readonlyposition: 3Position relative to the settlement centre.
Readonlytint: 3Wall or roof colour (linear RGB).
Readonlyuv: 2Walls: metres along the wall, metres above the ground floor. Roofs: pattern coordinates in metres.
Vertex attributes of building geometry (walls and roofs share them so both fit any BatchedMesh).