Sector
A sector is one square of the Galactic Empire map. Sectors are identified by signed X and Y numbers, such as 0 0 or -3 2. The conventional map directions are east for increasing X and south for increasing Y; north therefore makes Y more negative.
Size and local position
Each sector measures 10,000 by 10,000 displayed distance units. A ship's position has two parts: its sector and its local X/Y coordinates within that sector. Sector 0 0 at local position 5000 5000 is near the sector's center. Crossing an ordinary sector edge changes the sector number and continues the local position from the opposite side without teleporting the ship.
Internally, GE stores one continuous floating-point world coordinate on each axis. The sector number is the floor of that value; the fractional part supplies the local position. Thus a world X coordinate of -0.25 belongs to sector -1 at local X 7500, not to sector 0. Distances are calculated from continuous positions, so two ships on opposite sides of a sector boundary can still be very close. See Coordinate system for worked examples and the compass convention.
Contents and local numbering
A sector can contain ships, mines, planets, and wormholes. Ships and mines can move or disappear; they are not part of a fixed sector layout. The sector record instead holds the positions and types of its planets and wormholes, with separate records for the details of each object. Planets and wormholes share one sequence of numbers within that sector. Thus planet 1 or wormhole 2 identifies a local object for commands such as SCAN PLANET and ORBIT, not a galaxy-wide object number. Ship letters come from the observing player's scan table and are a different kind of identifier. A sector scan shows the nearby objects and their local numbers.
Sector 0 0
Sector 0 0 is the center sector and ordinarily the Neutral zone. It contains the standard Galactic Command locations, including Zygor, Tahanian Station, and the Enforcer Planet. It is a complete sector in its own right, not a point at the mathematical origin.
Discovery and the galaxy edge
The game does not create every possible sector at startup. A sector record is created the first time the game requests it. Scanning an unexplored sector can do this, but a scan is not required: the ship's nearby-planet and wormhole check also calls refresh(), which loads the current sector or creates it if it does not yet exist. Merely crossing a coordinate boundary is not itself the database operation. A ship passing through in hyperspace can leave sectors uncreated until a scan or another operation requests them.
In classic GE, the nearby-object check is gravity(), called for a user ship moving in normal space. Thus impulse travel into an unexplored sector can create it even without a scan, while a stopped ship does not invoke that particular check. In ge-next 0.3, the check was renamed proximity() and moved outside the moving-ship branch so a stopped ship near a planet could receive its beacon without scanning first. A stopped user ship in normal space can consequently create an unexplored sector on its next ship update. Gravity and wormhole hazards still require movement. In ordinary play, an impulse-moving ship will usually have created the sector already, so the stopped-ship difference is easy to miss.
When a newly created sector contains wormholes, the game also loads or creates their destination sectors and adds return wormholes where there is room. Generated sector contents persist; later visitors do not get a fresh random roll. The radius setting UNIVMAX limits playable sector numbers. At the default radius of 300, ge-next includes sectors -300 through 300 on both axes. Crossing the outer Galactic perimeter wraps or repels the ship according to UNIVWRAP.
See also
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