Buildings

A region's settlements are built from a small set of pieces that repeat, so the kit builds a building from its dimensions rather than from a stored mesh. One building is a platform the walls stand on, four walls and a roof, each given in metres from the ground. Its geometry is one mesh, so a building is one draw for its material.

How it works

flowchart TD
  OP[Building options: footprint, heights, wall thickness, roof kind] --> PL[Platform: a slab from the ground to the platform's top]
  PL --> WL[Four walls on the platform, each a box of the wall thickness]
  WL --> RK{Roof kind}
  RK -->|Flat| FR[A slab over the walls]
  RK -->|Conical| CR[A cone scaled to the footprint, standing on the walls' top]
  FR --> MG[Merged into one geometry]
  CR --> MG

• The pieces are boxes, and the walls are the boxes' inner ring. The platform spans the whole footprint. Each wall is a box along one edge, the two long walls running the full width and the two short walls fitting between them, so the four boxes meet at the corners without overlapping (createBoxesGeometry).
• A flat roof is one more box over the walls, its thickness its roof height.
• A conical roof is a cone scaled to the footprint. A unit cone is stretched to half the footprint's width and depth, so its base lies over the walls' outside edge on any rectangle, not only a square. Its apex stands the roof height above the walls.
• The result is merged into one geometry, the parts freed once merged (mergeGeometryParts).

The building is centred on the origin and stands on it, so a caller places it on the ground with its position. Natlan's tribes build with it, the People of the Springs' first building standing as a building landmark.

Key files