Cell of Interest

A cell of interest is the specific tile on a building or natural structure that Dupes, delivery systems, or outputs interact with. In Oxygen Not Included, many buildings do not use their full footprint for every action: a Dupe may stand on one tile to operate the building, materials may be delivered to a different tile, and the finished product may appear or be dropped from yet another tile. Knowing these cells is important for clean room layouts, automation, and making sure conveyors, sweepers, and floor tiles are placed where they can actually interact with the building.

Cells of interest are usually described with a coordinate system based on the building’s footprint. Rows are counted from the bottom upward, with A as the bottom row, B the second row, and so on. Columns are counted from left to right, with 1 as the leftmost tile. For example, A1 is the bottom-left cell of a building, while A2 is the second tile from the left on the bottom row. Some buildings have multiple valid interaction cells, while others have no delivery cell or no drop-off cell at all. In a few cases, the building can be rotated, which changes where the relevant tile is located.

The most common cell of interest types are:

• Dupe Interaction Cell: the tile Dupes must occupy to operate the building. This matters for motion sensors, lighting bonuses, carpet placement, and other tile-based effects.
• Delivery Cell: the tile that accepts item deliveries from Dupes or Auto-Sweepers.
• Material Drop-Off Cell: the tile where the building’s output is placed or emitted.

The exact cell depends on the building. For example, the Electric Grill uses the middle bottom cell for delivery, operation, and output, while the Compost places its output on the bottom-right cell even though the animation appears to show the middle. The Arcade Cabinet allows Dupe interaction from either the bottom-left or bottom-right cell, and both can be used at the same time. Some buildings also have special behavior: the Bottle Emptier places liquid in the adjacent bottom cell under its faucet, and the Conveyor Loader and Conveyor Receptacle use the conveyor connection point rather than a fixed visible tile in the same way as ordinary buildings.

Natural formations are also listed using cells of interest. Geysers, volcanos, and vents all follow the same Neutronium-based reference pattern for interaction and output. For these structures, the analysis interaction is one cell above the center-left Neutronium tile, and the material output is two cells above that same tile.

Understanding cells of interest helps with:

• placing Auto-Sweepers so they can reach the correct delivery or output tile
• positioning Duplicant movement, lights, and decor for the actual work tile
• aligning conveyor outputs, floor gaps, mesh tiles, and catch basins
• avoiding situations where a building is technically reachable, but not usable from the intended side

Because several buildings place their functional tile away from the visual center of the sprite, checking the cell of interest is often necessary when designing compact bases or automation-heavy production lines.