Keywords / Filters to select groups of ships in datafilecontent

[petervdmeer]

Problem Description

Some features like formation-flying, tagging of ships, locking/unlocking ship-fucntions and teleporting would benefit from (or even require) having the ability to select (groups of) operational ships, for example for formation-positions (only certain ships at certain formation positions) or for selecting which ships to tag or which ships to teleport along with the player.

We can discuss such ShipFilters in any of those feature-requests, but it seems valid to also have a separate ticket to discuss this specifically.

Related Issue Links

• formation-flying (feat: Formation flying functionality #4471)
• tagging of ships (Set, query and remove "identity tags" on ships from missions. #4930)
• teleporting (Allow mission writers to let time pass and to teleport in mission events #6018)
• locking/unlocking of certain features

Desired Solution

The LocationFilter class and the wiki on filtering (https://github.com/endless-sky/endless-sky/wiki/CreatingMissions#filters) seems to be a good starting location. What I would like to see is a specific type of filter that allows me to select active ships both from the player as well as non-player (for example escort) ships.

Some selection-criteria which I already came up with:

• flagship (explicit, special case)
• ships selected by a location filter
  • ships in the players system
  • ships in the players planet
  • ships in specific systems
  • ships in systems close to another system
• ships selected by attributes (having them or not having them, having an attribute not set)
• ship (static) properties
  • Cargo space
  • Nr of bunks
  • Type
  • Category
  • Certain outfits installed (or not installed)
• active (runtime) ship properties
  • Amount of cargo
  • Nr of Passengers
  • ships being carried
  • Nr of ships carried
  • Ships being disabled
  • Ships being parked
• Owner
  • Both player-owned as well as certain government owned
• Selected by player (not supported by the examples, but might be valuable for other usecases) => unlikely to be used often in story-content.

The feature should be available to be embedded in other features using some keyword. The keyword itself can be specific to the feature on top.

Alternative Approaches

Extending locationfilters or creating a new type of filter seem to be 2 different directions in which this can be implemented. I feel that a new type of filter (that can include location filters to select ships on a location) would work best.

Additional Context

No response

[xX-Dillinger-Xx]

Selected by player

I like the idea of being able to select certain ships, adding them to specific groups, and be able to issue commands to those groups. It adds some much needed fleet support. I know fleet play isn't the intended experience but it is defiantly a part of the game, particularly for 1st time players.
Case uses:

• getting freighters and other support groups to wait at a safe distance until my combat group has cleared the system.
• setting traps by placing group A out away from system center and then baiting enemy to chase me into the trap.

[petervdmeer]

Selected by player

I like the idea of being able to select certain ships, adding them to specific groups, and be able to issue commands to those groups. It adds some much needed fleet support.

This feature already exists (using numeric keys, with and without control) and is not what this feature-request is about.

I know fleet play isn't the intended experience but it is defiantly a part of the game, particularly for 1st time players. Case uses:

• getting freighters and other support groups to wait at a safe distance until my combat group has cleared the system.
• setting traps by placing group A out away from system center and then baiting enemy to chase me into the trap.

Yes, that is what I used group selection for as well, but that is not what this feature-request is for.