Walls and Floors

Purpose

In scope: placement, snapping, connections, variants, decorative trims, doors (placement)
Out of scope: decals, advanced materials

Units are game units (u), where 1 u = 1 Unity metre (~2 real-world metres). The grid is a 0.5 u sub-grid (IJ horizontal, K up); 1 u is only a display/simulation aggregation, never the placement step. See Grid system — the canonical source for grid dimensions, coordinate mapping, and the unit/scale convention.
Walls can be placed in 0.5 u increments, horizontal and vertical
Floors can be sized in 0.5 u increments

Types: solid tile
- Future types: fences, glass
Built from flat-ended modules (25×25, 25×50, 50×25, 50×50). Exposed ends use bevelled pieces (TL, TR, BL, BR, Left, Right, Top, Bottom)
Heights extend in 0.5 u increments only
Placement along cell edges in 0.5 u horizontal increments; corners and ends determined by neighbours
Prefer largest tiles first to minimise count, avoid 0.25 u residuals, pick correct bevels automatically
Optional trims 0.3 u wide at top and/or bottom and bevel when the wall bevels
Doors, windows, arches cut through wall
Intersections (top-down) use flat-ended pieces at T and cross joins
- Bevels only on exposed ends
Corners (side view overlap):

FB
FB
FFBB
FFFB

Types: solid tile
- Future types: glass, grate, grass
Built from wall modules rotated: 25×25, 25×50, 50×25, 50×50
Place in 0.5 u increments
Platforms only at 1 u stacks (~2 m) to create deck height; non-overlapping floors can be placed with 0.5 u increments
Bevel only on unfinished/exposed borders; at wall intersections, bevel only when no adjacent floor continues past the wall
Merge floor bevel with wall bottom bevel when applicable
Grid-aligned snapping with neighbour seam alignment
Choose minimal-count tiling with largest modules first; generate border strips as needed; apply bevels only to exposed edges