Procedural Buildings and Cities

Treat architecture as a compiler: decide the runtime package, produce and validate a serializable plan, then emit geometry. The plan owns massing, exposed surfaces, placements, material slots, and stable identity.

Process

1. Select the runtime package from mutability and repetition.

   Workload	Package
   Static building or chunk	merged indexed BufferGeometry per material slot
   Editable varied modules	BatchedMesh per compatible material slot
   Repeated identical topology	spatially paged InstancedMesh
   District-scale streaming	bounded chunks with projected-error LOD