Adjustable Plane Taxi Speed

Originated from embeddedt/OpenTTD-modded (Batch 1 port).

Feature

New game setting vehicle.plane_taxi_speed (Plane Taxi Speed), independently adjusts the speed limit for aircraft taxiing on the ground:

• Range 1–8, default 4 (= original taxi speed limit of 50 units)
• Higher values mean faster taxiing (1 → 12.5, 8 → 100)
• Works independently from other aircraft speed settings (plane_speed global multiplier), no interference

Setting Location

In-game Settings → Expert Settings → Vehicles, or in the configuration file openttd.cfg:

[vehicle]
plane_taxi_speed = 4

Implementation Notes

• Setting has SettingFlag::NoNetwork (server-authoritative, decided by the host in multiplayer)
• Uses XSLF extended feature gating (XSLFI_PLANE_TAXI_SPEED, version 1): when loading old saves, this feature does not exist → the setting stays at default value 4, does not break any old saves
• Taxi speed limit applies when the aircraft is in AS_RUNNING state (taxiing on ground), taking min(aircraft speed limit, taxi speed limit)

Involved Files

• src/aircraft_cmd.cpp (new SPEED_LIMIT_TAXI constant + taxi speed limit logic)
• src/table/settings/game_settings.ini (setting definition)
• src/settings_type.h (VehicleSettings::plane_taxi_speed)
• src/sl/extended_ver_sl.h/.cpp (XSLF feature registration)
• src/lang/english.txt (STR_CONFIG_SETTING_PLANE_TAXI_SPEED*)