Reduce fuel for fast-forwarded player flights.

This only has an effect for aircraft for which we have fuel consumption
data, but that's fine.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/1681

game/ato/flight.py

@@ -1,12 +1,13 @@
 from __future__ import annotations
 
 from datetime import datetime, timedelta
-from typing import Any, Optional, List, TYPE_CHECKING
+from typing import Any, List, Optional, TYPE_CHECKING
+
+from dcs.planes import C_101CC, C_101EB, Su_33
 
 from gen.flights.loadouts import Loadout
-
 from .flightroster import FlightRoster
-from .flightstate import Uninitialized, FlightState
+from .flightstate import FlightState, Uninitialized
 
 if TYPE_CHECKING:
     from game.dcs.aircrafttype import AircraftType
@@ -122,6 +123,18 @@ class Flight:
         self.roster.clear()
         self.squadron.claim_inventory(-self.count)
 
+    def max_takeoff_fuel(self) -> Optional[float]:
+        # Special case so Su 33 and C101 can take off
+        unit_type = self.unit_type.dcs_unit_type
+        if unit_type == Su_33:
+            if self.flight_type.is_air_to_air:
+                return Su_33.fuel_max / 2.2
+            else:
+                return Su_33.fuel_max * 0.8
+        elif unit_type in {C_101EB, C_101CC}:
+            return unit_type.fuel_max * 0.5
+        return None
+
     def __repr__(self) -> str:
         if self.custom_name:
             return f"{self.custom_name} {self.count} x {self.unit_type}"

game/ato/flightstate/flightstate.py

@@ -37,3 +37,9 @@ class FlightState(ABC):
 
     def a2a_commit_region(self) -> Optional[ThreatPoly]:
         return None
+
+    def estimate_fuel(self) -> float:
+        """Returns the estimated remaining fuel **in kilograms**."""
+        if (max_takeoff_fuel := self.flight.max_takeoff_fuel()) is not None:
+            return max_takeoff_fuel
+        return self.flight.unit_type.dcs_unit_type.fuel_max

game/ato/flightstate/inflight.py

@@ -11,7 +11,7 @@ from game.ato.flightstate.flightstate import FlightState
 from game.ato.flightwaypoint import FlightWaypoint
 from game.ato.flightwaypointtype import FlightWaypointType
 from game.ato.starttype import StartType
-from game.utils import Distance, Speed, meters
+from game.utils import Distance, LBS_TO_KG, Speed, meters, pairwise
 from gen.flights.flightplan import LoiterFlightPlan
 
 if TYPE_CHECKING:
@@ -83,6 +83,30 @@ class InFlight(FlightState):
             self.current_waypoint, self.next_waypoint
         )
 
+    def estimate_fuel_at_current_waypoint(self) -> float:
+        initial_fuel = super().estimate_fuel()
+        if self.flight.unit_type.fuel_consumption is None:
+            return initial_fuel
+        initial_fuel -= self.flight.unit_type.fuel_consumption.taxi * LBS_TO_KG
+        waypoints = self.flight.flight_plan.waypoints[: self.waypoint_index + 1]
+        for a, b in pairwise(waypoints[:-1]):
+            consumption = self.flight.flight_plan.fuel_consumption_between_points(a, b)
+            assert consumption is not None
+            initial_fuel -= consumption * LBS_TO_KG
+        return initial_fuel
+
+    def estimate_fuel(self) -> float:
+        initial_fuel = self.estimate_fuel_at_current_waypoint()
+        ppm = self.flight.flight_plan.fuel_rate_to_between_points(
+            self.current_waypoint, self.next_waypoint
+        )
+        if ppm is None:
+            return initial_fuel
+        position = self.estimate_position()
+        distance = meters(self.current_waypoint.position.distance_to_point(position))
+        consumption = distance.nautical_miles * ppm * LBS_TO_KG
+        return initial_fuel - consumption
+
     def next_waypoint_state(self) -> FlightState:
         from game.ato.flightstate.loiter import Loiter
         from game.ato.flightstate.racetrack import RaceTrack

game/ato/flightstate/loiter.py

@@ -29,6 +29,10 @@ class Loiter(InFlight):
     def estimate_speed(self) -> Speed:
         return self.flight.unit_type.preferred_patrol_speed(self.estimate_altitude()[0])
 
+    def estimate_fuel(self) -> float:
+        # TODO: Estimate loiter consumption per minute?
+        return self.estimate_fuel_at_current_waypoint()
+
     def next_waypoint_state(self) -> FlightState:
         # Do not automatically advance to the next waypoint. Just proceed from the
         # current one with the normal flying state.

game/ato/flightstate/racetrack.py

@@ -40,6 +40,10 @@ class RaceTrack(InFlight):
     def estimate_speed(self) -> Speed:
         return self.flight.unit_type.preferred_patrol_speed(self.estimate_altitude()[0])
 
+    def estimate_fuel(self) -> float:
+        # TODO: Estimate loiter consumption per minute?
+        return self.estimate_fuel_at_current_waypoint()
+
     def travel_time_between_waypoints(self) -> timedelta:
         return self.patrol_duration
 

game/ato/flightstate/takeoff.py

@@ -7,6 +7,7 @@ from typing import TYPE_CHECKING
 from .flightstate import FlightState
 from .inflight import InFlight
 from ..starttype import StartType
+from ...utils import LBS_TO_KG
 
 if TYPE_CHECKING:
     from game.ato.flight import Flight
@@ -33,6 +34,12 @@ class Takeoff(FlightState):
     def spawn_type(self) -> StartType:
         return StartType.RUNWAY
 
+    def estimate_fuel(self) -> float:
+        initial_fuel = super().estimate_fuel()
+        if self.flight.unit_type.fuel_consumption is None:
+            return initial_fuel
+        return initial_fuel - self.flight.unit_type.fuel_consumption.taxi * LBS_TO_KG
+
     def should_halt_sim(self, enemy_aircraft_coverage: AircraftEngagementZones) -> bool:
         if (
             self.flight.client_count > 0

game/missiongenerator/aircraft/flightgroupconfigurator.py

@@ -6,8 +6,7 @@ from typing import Any, Optional, TYPE_CHECKING
 
 from dcs import Mission
 from dcs.flyingunit import FlyingUnit
-from dcs.planes import C_101CC, C_101EB, F_14B, Su_33
+from dcs.planes import F_14B
-from dcs.task import CAP
 from dcs.unit import Skill
 from dcs.unitgroup import FlyingGroup
 
@@ -208,14 +207,21 @@ class FlightGroupConfigurator:
             pylon.equip(self.group, weapon)
 
     def setup_fuel(self) -> None:
-        # Special case so Su 33 and C101 can take off
+        fuel = self.flight.state.estimate_fuel()
-        unit_type = self.flight.unit_type.dcs_unit_type
+        if fuel < 0:
-        if unit_type == Su_33:
+            logging.warning(
-            for unit in self.group.units:
+                f"Flight {self.flight} is estimated to have no fuel at mission start. "
-                if self.group.task == CAP:
+                "This estimate does not account for external fuel tanks. Setting "
-                    unit.fuel = Su_33.fuel_max / 2.2
+                "starting fuel to 100kg."
-                else:
+            )
-                    unit.fuel = Su_33.fuel_max * 0.8
+            fuel = 100
-        elif unit_type in {C_101EB, C_101CC}:
+        for unit, pilot in zip(self.group.units, self.flight.roster.pilots):
-            for unit in self.group.units:
+            if pilot is not None and pilot.player:
-                unit.fuel = unit_type.fuel_max * 0.5
+                unit.fuel = fuel
+            elif (max_takeoff_fuel := self.flight.max_takeoff_fuel()) is not None:
+                unit.fuel = max_takeoff_fuel
+            else:
+                # pydcs arbitrarily reduces the fuel of in-flight spawns by 10%. We do
+                # our own tracking, so undo that.
+                # https://github.com/pydcs/dcs/commit/303a81a8e0c778599fe136dd22cb2ae8123639a6
+                unit.fuel = self.flight.unit_type.dcs_unit_type.fuel_max

game/missiongenerator/aircraft/waypoints/waypointgenerator.py

@@ -18,7 +18,7 @@ from game.ato.starttype import StartType
 from game.missiongenerator.airsupport import AirSupport
 from game.settings import Settings
 from game.theater import ControlPointType
-from game.utils import meters, pairwise
+from game.utils import pairwise
 from .baiingress import BaiIngressBuilder
 from .cargostop import CargoStopBuilder
 from .casingress import CasIngressBuilder
@@ -145,19 +145,6 @@ class WaypointGenerator:
         if self.flight.unit_type.fuel_consumption is None:
             return
 
-        combat_speed_types = {
-            FlightWaypointType.INGRESS_BAI,
-            FlightWaypointType.INGRESS_CAS,
-            FlightWaypointType.INGRESS_DEAD,
-            FlightWaypointType.INGRESS_ESCORT,
-            FlightWaypointType.INGRESS_OCA_AIRCRAFT,
-            FlightWaypointType.INGRESS_OCA_RUNWAY,
-            FlightWaypointType.INGRESS_SEAD,
-            FlightWaypointType.INGRESS_STRIKE,
-            FlightWaypointType.INGRESS_SWEEP,
-            FlightWaypointType.SPLIT,
-        } | set(TARGET_WAYPOINTS)
-
         consumption = self.flight.unit_type.fuel_consumption
         min_fuel: float = consumption.min_safe
 
@@ -174,14 +161,10 @@ class WaypointGenerator:
             return
 
         for b, a in pairwise(main_flight_plan):
-            distance = meters(a.position.distance_to_point(b.position))
+            for_leg = self.flight.flight_plan.fuel_consumption_between_points(a, b)
-            if a.waypoint_type is FlightWaypointType.TAKEOFF:
+            if for_leg is None:
-                ppm = consumption.climb
+                continue
-            elif b.waypoint_type in combat_speed_types:
+            min_fuel += for_leg
-                ppm = consumption.combat
-            else:
-                ppm = consumption.cruise
-            min_fuel += distance.nautical_miles * ppm
             a.min_fuel = min_fuel
 
     def set_takeoff_time(self, waypoint: FlightWaypoint) -> timedelta:

game/utils.py

@@ -5,7 +5,7 @@ import math
 import random
 from collections import Iterable
 from dataclasses import dataclass
-from typing import Union, Any, TypeVar
+from typing import TypeVar, Union
 
 METERS_TO_FEET = 3.28084
 FEET_TO_METERS = 1 / METERS_TO_FEET
@@ -20,6 +20,8 @@ KPH_TO_MS = 1 / MS_TO_KPH
 INHG_TO_HPA = 33.86389
 INHG_TO_MMHG = 25.400002776728
 
+LBS_TO_KG = 0.453592
+
 
 @dataclass(frozen=True, order=True)
 class Distance:

gen/flights/flightplan.py

@@ -19,30 +19,30 @@ from dcs.mapping import Point
 from dcs.unit import Unit
 from shapely.geometry import Point as ShapelyPoint
 
+from game.ato.flighttype import FlightType
+from game.ato.flightwaypoint import FlightWaypoint
+from game.ato.flightwaypointtype import FlightWaypointType
 from game.ato.starttype import StartType
 from game.data.doctrine import Doctrine
 from game.dcs.aircrafttype import FuelConsumption
-from game.flightplan import IpZoneGeometry, JoinZoneGeometry, HoldZoneGeometry
+from game.flightplan import HoldZoneGeometry, IpZoneGeometry, JoinZoneGeometry
 from game.theater import (
     Airfield,
+    ConflictTheater,
     ControlPoint,
     FrontLine,
     MissionTarget,
+    NavalControlPoint,
     SamGroundObject,
     TheaterGroundObject,
-    NavalControlPoint,
-    ConflictTheater,
 )
 from game.theater.theatergroundobject import (
+    BuildingGroundObject,
     EwrGroundObject,
     NavalGroundObject,
-    BuildingGroundObject,
 )
-from game.utils import Distance, Heading, Speed, feet, meters, nautical_miles, knots
+from game.utils import Distance, Heading, Speed, feet, knots, meters, nautical_miles
 from .closestairfields import ObjectiveDistanceCache
-from game.ato.flighttype import FlightType
-from game.ato.flightwaypointtype import FlightWaypointType
-from game.ato.flightwaypoint import FlightWaypoint
 from .traveltime import GroundSpeed, TravelTime
 from .waypointbuilder import StrikeTarget, WaypointBuilder
 
@@ -126,6 +126,30 @@ class FlightPlan:
     def speed_between_waypoints(self, a: FlightWaypoint, b: FlightWaypoint) -> Speed:
         return self.best_speed_between_waypoints(a, b)
 
+    @property
+    def combat_speed_waypoints(self) -> set[FlightWaypoint]:
+        raise NotImplementedError
+
+    def fuel_consumption_between_points(
+        self, a: FlightWaypoint, b: FlightWaypoint
+    ) -> Optional[float]:
+        ppm = self.fuel_rate_to_between_points(a, b)
+        if ppm is None:
+            return None
+        distance = meters(a.position.distance_to_point(b.position))
+        return distance.nautical_miles * ppm
+
+    def fuel_rate_to_between_points(
+        self, a: FlightWaypoint, b: FlightWaypoint
+    ) -> Optional[float]:
+        if self.flight.unit_type.fuel_consumption is None:
+            return None
+        if a.waypoint_type is FlightWaypointType.TAKEOFF:
+            return self.flight.unit_type.fuel_consumption.climb
+        if b in self.combat_speed_waypoints:
+            return self.flight.unit_type.fuel_consumption.combat
+        return self.flight.unit_type.fuel_consumption.cruise
+
     @property
     def tot_waypoint(self) -> Optional[FlightWaypoint]:
         """The waypoint that is associated with the package TOT, or None.
@@ -343,9 +367,13 @@ class FormationFlightPlan(LoiterFlightPlan):
         raise NotImplementedError
 
     @property
-    def package_speed_waypoints(self) -> Set[FlightWaypoint]:
+    def package_speed_waypoints(self) -> set[FlightWaypoint]:
         raise NotImplementedError
 
+    @property
+    def combat_speed_waypoints(self) -> set[FlightWaypoint]:
+        return self.package_speed_waypoints
+
     @property
     def tot_waypoint(self) -> Optional[FlightWaypoint]:
         raise NotImplementedError
@@ -595,7 +623,7 @@ class StrikeFlightPlan(FormationFlightPlan):
         yield self.bullseye
 
     @property
-    def package_speed_waypoints(self) -> Set[FlightWaypoint]:
+    def package_speed_waypoints(self) -> set[FlightWaypoint]:
         return {
             self.ingress,
             self.split,