Buildings and Building Tool - Gears of War: E-Day

Nearly every building in Kalona comes out of the building tool.

Nearly every building in Kalona comes out of the building tool.

How a building is put together in a very simplified way

How a building is put together in a very simplified way

Every building is three layers: a top, a body that repeats per floor, and a base.

Every building is three layers: a top, a body that repeats per floor, and a base.

Building tool in action, part 1: selecting and editing parts of a facade in the editor. Footage from Epic's public Inside Unreal broadcast (link in the description).

Storefronts swap in and out of the base.

Storefronts swap in and out of the base.

Interior add-ons behind street-level windows.

Interior add-ons behind street-level windows.

Interior shell: a footprint spline drives walls, floor and ceiling that match the exterior.

Interior shell: a footprint spline drives walls, floor and ceiling that match the exterior.

Accessories layered on the architecture: fire escapes, drainpipes, awnings and AC units.

Accessories layered on the architecture: fire escapes, drainpipes, awnings and AC units.

Roof trims and props finish the silhouette.

Roof trims and props finish the silhouette.

Recipes: the same system at any size, intact or damaged.

Recipes: the same system at any size, intact or damaged.

Part 2: changing modules and recipes on the same building.

Custom add-ons for hero moments: arches, porticos and destruction.

Custom add-ons for hero moments: arches, porticos and destruction.

Mixed residential facades along one street.

Mixed residential facades along one street.

A civic stone facade: a different recipe on the same system.

A civic stone facade: a different recipe on the same system.

Looking up between two blocks.

Looking up between two blocks.

Corners and angled blocks are handled by the tool.

Corners and angled blocks are handled by the tool.

Fire escapes and back alleys between the main roads.

Fire escapes and back alleys between the main roads.

Usage of the building tool on a Public parking with an unique kit.

Usage of the building tool on a Public parking with an unique kit.

The bar and grill block in the middle of a fight.

The bar and grill block in the middle of a fight.

One recipe family across a whole street, at different heights and footprints.

One recipe family across a whole street, at different heights and footprints.

Building scale under the sky train.

Building scale under the sky train.

Storeys, cornices and fire escapes repeating up the block.

Storeys, cornices and fire escapes repeating up the block.

Ground-floor detail: arcades, recesses and shopfronts.

Ground-floor detail: arcades, recesses and shopfronts.

Residential blocks lining a Downtown street.

Residential blocks lining a Downtown street.

A newsstand corner with a damaged tower behind it.

A newsstand corner with a damaged tower behind it.

Industrial and residential recipes side by side.

Industrial and residential recipes side by side.

Fire escapes, signage and AC units layered on the architecture.

Fire escapes, signage and AC units layered on the architecture.

Part 3: swapping style kits and layering in VFX like fire damage.

Kalona is a city, so buildings were one of the biggest content challenges on the project. Almost every building in the game comes from one tool.

Bruno Parillo (Behaviour Interactive) was in charge of it, and I was his art-side partner from the first prototype on. Bruno built the system; I focused on shaping it for the environment team:
• Needs: where the tool could speed up the workflow, and which features would remove the biggest time sinks
• UX: what artists see, what's exposed, what stays hidden, and keeping it fast in the editor
• Problem solving: working through technical challenges together and deciding where an edge case deserved support and where the common case should stay simple
• Recipes: authoring most of the building recipes, and setting the rules for how facades break down into packed level actors and static meshes so pieces reuse across the whole city and stay Nanite-friendly

How a building is put together:
• Three layers: a top, a body that repeats per floor, and a base
• Swappable modules: storefronts, interior add-ons, accessories, roof trims and props
• Interior shell: a footprint spline drives walls, floor and ceiling that match the exterior
• Recipes: one setup that scales to any size, intact or damaged
• Custom add-ons for hero buildings
It also handles custom insets anywhere on a facade, material breakup across a whole facade, and corners and angled blocks.

It had to work for level design too: anything sticking out of a facade was built to cover-compliant metrics, so designers could rely on whatever the tool generated.

The infographics show a handful of examples; there are dozens more across the city.

The real test of a tool is whether artists reach for it without being asked. This one became the default way to build Kalona. Thanks Bruno, one of my favorite collaborations of my career.

And a huge shout-out to the entire Environment Tech and Level Art teams, who took this tool and built a whole city with it.

The video clips come from a public broadcast: "How The Coalition Brought Gears of War: E-Day to Life in Unreal Engine 5 | Inside Unreal" https://www.youtube.com/live/S91UEeVdspo

More from this series:
• Kalona City and Downtown District: https://www.artstation.com/artwork/rzXXQm
• Downtown District: https://www.artstation.com/artwork/31bb02
• Theater and Tools: https://www.artstation.com/artwork/q0ooWD
• Downtown Photography Trip: https://www.artstation.com/artwork/LaZZYA

Date
November 7, 2026