ID64
This is an ID format used by the game to identify systems and stellar bodies. The ID is represented as a 64-bit integer.
Format
The 64-bit integer is effectively a structure, with different parts of the bitfield representing different aspects of the system's features.
These parts are:
- Mass code (3 bits) - the mass code of the system, with a = 0 through to h = 7
- Z boxel (0-7 bits) - the Z boxel (within-sector) coordinate of the system
- Z sector (7 bits) - the Z sector coordinate of the system
- Y boxel (0-7 bits) - the Y boxel (within-sector) coordinate of the system
- Y sector (6 bits) - the Y sector coordinate of the system
- X boxel (0-7 bits) - the X boxel (within-sector) coordinate of the system
- X sector (7 bits) - the X sector coordinate of the system
- N2 (11-32 bits) - the N2 number (within-boxel identifier) of the system
- Body ID (9 bits) - the ID of the body within the system; for systems this is always 0 (representing the arrival star)
Note that the X/Y/Z boxel coordinates and the N2 number have variable sizes; this is because the amount of space taken by these pieces of data is different depending on the mass code.
The following image shows the bitfield for each mass code:
Use
The format first became visible with the release of E:D 2.2, as it is used in the VisitedStarsCache data file used to track which stars the player has visited.
It is also used when storing the current active route between game sessions; this is how the stellar body part at the top end of the ID were discovered (since you are able to set a route to planets/stations).