Customising Buildings

This page covers everything that changes what a building is made of — which kind it is, which palette it wears, how much geometry it gets, and the optional extras. These settings appear in the Generation Settings ▸ Geometry foldout on every pane that generates buildings, and as per-district fields on BCG_BuildingZone.

Everything here is deterministic. Changing a setting changes what you get, but the same settings plus the same seed always give the same building.

The four archetypes

An archetype is a structural preset — the rules the generator follows for that kind of building.

Switching archetype loads a starting point for that kind of building. Every field stays editable afterwards — these are defaults, not constraints:

Multi-volume towers

Towers are the only archetype that can break out of a single box, and only when they are big enough to justify it: 7 or more floors, at least 6 cells wide and 5 cells deep. Below that threshold — and for every other archetype at any size — you get a single slab.

When a tower does qualify, its seed picks between a plain slab, a setback (stepping in as it rises), a podium (a wide base with a tower on top) or an L-plan. This is the single biggest reason a downtown district looks varied while a low-rise one looks uniform.

Houses

House geometry is deliberately special-cased. The roof pitch is a pure function of the seed — 32 + (seed mod 9) degrees, so always between 32° and 40° — with the ridge running along the building's longer axis. A chimney appears 70% of the time, its side and position along the ridge both seeded. Houses have no parapet, no roof clutter and no massing variants, so the parapet fields are ignored for them.

Palettes

Texture Variant picks which of four palettes a building wears:

All four share one atlas layout, so a palette swap is genuinely free — same mesh, different material. On the fills that place many buildings, the Variant Mix checkboxes control which palettes are eligible: tick only C for a glass financial district, drop B for a city with no brick.

Detail levels

The Detail dropdown picks how much geometry represents a building. Crucially, it does not change which building you get — the same seed produces the same design at every tier, just with more or less geometry describing it.

What Detailed adds

• Recessed relief on every facade style. Styles that were flush gain the same recessed-opening treatment the others already had, plus window sills and mullion divider bars inside each opening.
• Real balconies — an actual slab, railing posts and a top rail per cell, instead of a flat painted band.
• Cornices and trim — a parapet coping profile and corner pilasters on block edges.
• Storefront depth — recessed entry cells and pilasters between shop windows.
• House details — window shutters, a door canopy and porch stoop, and a chimney cap.
• Richer roof clutter — the same clutter boxes, but each with a lip, legs and a pipe.

None of this consumes any extra randomness. Every Detailed-only feature is either always-present geometry or a pure function of the seed, which is why switching tiers never changes the design.

What it costs

These are pinned reference measurements from the package's own regression tests, with rooftop props and facade extras off so the comparison is like-for-like:

(Vertex counts.) Apartments and houses show the largest multipliers because they gain the most per-cell geometry — balconies on one, shutters and porches on the other. A Standard house is close to a decorated box, which is exactly what makes it cheap.

Two pieces of guidance:

1. Pair Detailed with Generate LODs. A Detailed building gets a three-level LOD chain (Detailed → Standard → Simple), so the extra triangles only cost anything close up. Without LODs, a Detailed building carries its full vertex count at every distance, including when it is twelve pixels tall. See Optimising ▸ LODs.
2. On mobile, stay on Standard or Simple. Detailed is a desktop, foreground-only tier. It is fine for a handful of hero buildings near the camera; it is not what you fill a mobile skyline with.

Detail is available from every workflow, and as a per-district field on BCG_BuildingZone, so you can run Detailed in the block the player walks through and Simple everywhere else.

Rooftop and storefront props

Rooftop Props (on by default) adds silhouette props — the things that stop a skyline reading as a row of boxes:

The rooftop billboard's face reuses the lit-window band of the atlas, so it part-glows at night along with the windows, at no extra cost.

Turning props off reproduces the pre-props geometry exactly. Turning them on means a given seed's roof clutter differs from what that seed produced before props existed — the props draw from the same random sequence. That is expected and documented; it is not a bug, and it only affects buildings you generate from now on.

Facade extras

Facade Extras (on by default) adds small seeded set-dressing to walls: air-conditioning units under some window cells, and wall vents. It applies to Tower, Shop and Apartment; House is untouched.

It is independent of detail level and works the same at Standard and Detailed. Simple truncates it, along with everything else in the tail.

Turning it off reproduces the extras-free geometry byte-for-byte.

Lit signage

Lit Signage adds vertical corner sign strips to tall towers (10+ floors, up to two of them) and a lit fascia strip over a shop's storefront. The strips are mapped into the atlas's lit-window band, so they glow at night through the same emission path as the windows — no new textures, no real lights, still one material and one draw call per building.

The engine default is off, for byte-compatibility with scenes made before signage existed. The window's toggle defaults on for new work, so buildings you generate now get signs while nothing existing changes retroactively.

Turning a blockout into buildings

If you prefer to design a skyline by hand, block it out with plain boxes — any object with a BoxCollider or a mesh; scaled cubes are ideal — select them, and run Replace Greyboxes With Buildings from 2 Build ▸ Greybox.

Each box becomes a generated building matching its footprint, height, base height and yaw (snapped to the nearest 90°).

• The box defines the intent. There is no ground snapping (the box's own base is the base) and no random reseed — the seed is a stable hash of the box's name. Re-running a re-blocked scene reproduces the same buildings, and renaming one box rerolls just that building.
• The archetype is inferred from shape: tall becomes a Tower, mid-rise an Apartment, low and wide a Shop, low and small a House. Floors and window cells are fitted to the box's dimensions.
• Placement still routes through the anti-overlap guard. Generated output, road pieces and zone markers are never mistaken for greyboxes. One Undo restores the boxes.

Four settings have no effect on greybox replacement either way, and the pane says so: Snap To Ground and Ground Layers (the box's base already decides the height), Mesh Variety (the seed is always the box-name hash) and Reuse Existing Assets (replacement always reuses a matching asset when saving prefabs).

The menu-item version of this command uses quick-blockout defaults instead of the pane's settings: scene instances with no assets written, no lightmap UVs, no LODs, Standard detail, props and extras on. Run it from the pane when you want your own settings honoured.

How mesh files stay separate

Because these options change geometry, the tool must never let one option's mesh overwrite another's. Generated mesh files carry short name tags recording what built them — props, detail tier, extras and signage each add a tag — so a props-on mesh and a props-off mesh are always different files at the same size and seed.

You do not need to think about this day to day. It matters when you flip an option and want to know whether your existing buildings changed: they did not. The tag table is in Reference ▸ Mesh name tags.

Common questions

I switched to Detailed and my building looks the same shape. That is correct. Detail changes how much geometry describes the design, not the design. Look at the window reveals, sills and balconies.

My towers are all plain boxes. They are below the massing threshold — multi-volume shapes need 7+ floors and at least 6 × 5 cells.

Can I add my own props or facades? Not through the tool. You can repaint the texture atlas — see Atlas Layout — and you can of course parent your own objects to a generated building in the scene.

Why did my old buildings not get signage after I turned it on? Nothing changes retroactively. Regenerate them, or refill the district, to pick up new content options.

Where to go next

• Materials and Lighting — palettes, night glow and fake interiors.
• Optimising — LODs, and what Detailed actually costs you.
• Reference — the seed contract and every setting's default.