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Radar/infobox The radar triggers charting of the map of the force it belongs to.

It can be used to provide a small area of remote vision on the map; it also allows periodic scanning of distant chunks around it. Radar has a high power demand (300kW) so a radar indirectly contributes to Pollution when powered by Boilers and steam engines. The radar will be attacked by enemies that come within very close range, like turrets, but will not attract biters from long range like polluting structures do. The radar will show enemy lifeforms and structures, as well as trains, cars, and other players in the scanned area.

Nearby Pulse Scanning

Radar continuously charts a charting area of 100x100 tiles. Which mean, that you most times chart 7x7 Chunk (224x224 Tiles), centered on the chunk the radar occupies. This nearby area is updated as a single pulse approximately every second. At reduced power levels, this nearby pulse scan will take longer, which can lead to 'blinking' on the player's map similar to the long range scan. This is particularly noticeable at dawn and dusk on solar powered radar stations.

At 20% power the radar will pulse about every 4 seconds which will still keep the nearby area continuously lit on the map, but will provide reduced detail. 20% power can be achieved by a single solar panel, or by using one isolating accumulator for every 5 radars.

Long Range Survey Scanning

Radar charts one distant Chunk every time the sector scanning progress bar fills. This will take 33.333 seconds, if the Radar is receiving full power. Mouse-over or click-open the radar details to see this progress bar. Long range scanning is visible on the map as a single chunk lighting up for several seconds, then slowly darkening.

  • It scans the unexplored chunks first, represented by the black areas on the map.
  • One chunk scan takes 10 MJ of energy to complete. Since the Radar draws 300 kW of power, it takes 10 MJ / 300 kW = 33.333... seconds to scan one chunk.
  • This is done in an 29x29 chunks around the Radar, excluding the nearby 7x7 chunk.
    • With a total number of 797 chunks (29x29 - 7x7), it takes one radar 7 hours 20 minutes to complete one full scan cycle.
  • If everything is already explored it continues to scan by re-scanning the longest-ago scanned chunk within range.
  • Multiple radars will share long-range chunks, reducing the amount of time it takes to complete long-range survey scanning.
    • This is a smart process, meaning that the radars will not scan chunks currently being scanned by other radars.

It is possible that a new alien nest will appear in a previously scanned chunk; just because you don't see it on the map, don't be taken unawares.


Something easily missed is that Radars give a line of sight around them, this is good for keeping tabs on distant bases if they get attacked and to see how big the attack is. The radar's LOS updates once every second, so keeping one or two around your base could prove to be an early warning system. Keep in mind the update rate for the LOS of the radar is not the same as the rate at which the radar will reveal unexplored terrain, which updates once every ~30 seconds. You can see the LOS given in the image below, taken from map view.

File:Radar Coverage.jpg


If a chunk is scanned by a radar or player, the image of that chunk that is copied into the map of the players of this surface force (every force has it's own map).

This procedure is called "charting".

Charting Process

If the contents of a chunk changes between two ticks, the content of that chunk is "charted" into the map. The map is just a bitmap, a picture. See below. You can see the entities moving, you can see enemies walking. Every entity is represented by one ore more pixels. Not every entity is drawn. What's drawn and in which color etc. is configurable and there are also mods, that changes this.

Charting Decay Time / Fog of War

Once a scan for a chunk is triggered, it keeps actively charted for 10 seconds. This effect can also be seen: In the map that chunk is highlighted and dims within 10 seconds to dark-grey.

If charting is not repeated within the 10 seconds, the charting process stops for this chunk after 10 seconds and is not longer updated. What you see after that time is the last charted picture for that chunk (also called "fog of war").

Once a new scan has been triggered the chunk keeps again charted for 10 seconds.

While charting one chunk is quite fast, charting of very much chunks, that changes each tick can become a problem in big maps. Because of that, it is recommended to use not more radars than really needed.

The Map

That is just a bitmap (graphics). The map for each force is stored with a save. Uncharted areas (never charted before) keep black and are not saved.

Charting-Area vs. Charted Chunks

For example: A radar actively charts an charting-area of 100x100 tiles. This means: Each chunk, that is touched by the charting-area is charted. Which means, that you nearly always chart a bigger area than defined in charting-area.

Visible Area vs. Charted

Like in reality there is a difference between what a player can "see" and what of that is charted. A player can see a much bigger area (use for example this console-command: "/c game.player.zoom=0.1"), than what is charted. This depends in normal game for example on your screen-resolution. The charting has nothing to do with that, it depends only on charting area.

Charting entities

The default game has two sources of triggering charting: The player and radars.


  • 0.11.11:
    • Radar ignores chunks outside the map radius.
  • 0.9.0:
    • Halved radar electricity consumption.
  • 0.7.3:
    • Radar continues refreshing chunks after all chunks in range have been discovered.

See also