Files
OpenRA/OpenRA.Mods.Common/Activities/Air/FlyAttack.cs
2019-03-04 18:26:42 +00:00

126 lines
4.8 KiB
C#

#region Copyright & License Information
/*
* Copyright 2007-2019 The OpenRA Developers (see AUTHORS)
* This file is part of OpenRA, which is free software. It is made
* available to you under the terms of the GNU General Public License
* as published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version. For more
* information, see COPYING.
*/
#endregion
using System.Linq;
using OpenRA.Activities;
using OpenRA.Mods.Common.Traits;
using OpenRA.Primitives;
using OpenRA.Traits;
namespace OpenRA.Mods.Common.Activities
{
public class FlyAttack : Activity
{
readonly Aircraft aircraft;
readonly AttackAircraft attackAircraft;
readonly Rearmable rearmable;
Target target;
Target lastVisibleTarget;
WDist lastVisibleMaximumRange;
bool useLastVisibleTarget;
int ticksUntilTurn;
public FlyAttack(Actor self, Target target)
{
this.target = target;
aircraft = self.Trait<Aircraft>();
attackAircraft = self.Trait<AttackAircraft>();
rearmable = self.TraitOrDefault<Rearmable>();
ticksUntilTurn = attackAircraft.AttackAircraftInfo.AttackTurnDelay;
// The target may become hidden between the initial order request and the first tick (e.g. if queued)
// Moving to any position (even if quite stale) is still better than immediately giving up
if ((target.Type == TargetType.Actor && target.Actor.CanBeViewedByPlayer(self.Owner))
|| target.Type == TargetType.FrozenActor || target.Type == TargetType.Terrain)
{
lastVisibleTarget = Target.FromPos(target.CenterPosition);
lastVisibleMaximumRange = attackAircraft.GetMaximumRangeVersusTarget(target);
}
}
public override Activity Tick(Actor self)
{
// Refuse to take off if it would land immediately again.
if (aircraft.ForceLanding)
Cancel(self);
if (IsCanceled)
return NextActivity;
bool targetIsHiddenActor;
target = target.Recalculate(self.Owner, out targetIsHiddenActor);
if (!targetIsHiddenActor && target.Type == TargetType.Actor)
{
lastVisibleTarget = Target.FromTargetPositions(target);
lastVisibleMaximumRange = attackAircraft.GetMaximumRangeVersusTarget(target);
}
var oldUseLastVisibleTarget = useLastVisibleTarget;
useLastVisibleTarget = targetIsHiddenActor || !target.IsValidFor(self);
// Update target lines if required
if (useLastVisibleTarget != oldUseLastVisibleTarget)
self.SetTargetLine(useLastVisibleTarget ? lastVisibleTarget : target, Color.Red, false);
// Target is hidden or dead, and we don't have a fallback position to move towards
if (useLastVisibleTarget && !lastVisibleTarget.IsValidFor(self))
return NextActivity;
// If all valid weapons have depleted their ammo and Rearmable trait exists, return to RearmActor to reload and then resume the activity
if (rearmable != null && !useLastVisibleTarget && attackAircraft.Armaments.All(x => x.IsTraitPaused || !x.Weapon.IsValidAgainst(target, self.World, self)))
return ActivityUtils.SequenceActivities(new ReturnToBase(self, aircraft.Info.AbortOnResupply), this);
var pos = self.CenterPosition;
var checkTarget = useLastVisibleTarget ? lastVisibleTarget : target;
// We don't know where the target actually is, so move to where we last saw it
if (useLastVisibleTarget)
{
// We've reached the assumed position but it is not there - give up
if (checkTarget.IsInRange(pos, lastVisibleMaximumRange))
return NextActivity;
// Fly towards the last known position
return ActivityUtils.SequenceActivities(
new Fly(self, target, WDist.Zero, lastVisibleMaximumRange, checkTarget.CenterPosition, Color.Red),
this);
}
// If we reach here the target is guaranteed to be both visible and alive, so use target instead of checkTarget.
// The target may not be in range, but try attacking anyway...
attackAircraft.DoAttack(self, target);
if (ChildActivity == null)
{
// TODO: This should fire each weapon at its maximum range
if (attackAircraft != null && target.IsInRange(self.CenterPosition, attackAircraft.GetMinimumRange()))
ChildActivity = ActivityUtils.SequenceActivities(
new FlyTimed(ticksUntilTurn, self),
new Fly(self, target, checkTarget.CenterPosition, Color.Red),
new FlyTimed(ticksUntilTurn, self));
else
ChildActivity = ActivityUtils.SequenceActivities(
new Fly(self, target, checkTarget.CenterPosition, Color.Red),
new FlyTimed(ticksUntilTurn, self));
// HACK: This needs to be done in this round-about way because TakeOff doesn't behave as expected when it doesn't have a NextActivity.
if (self.World.Map.DistanceAboveTerrain(self.CenterPosition).Length < aircraft.Info.MinAirborneAltitude)
ChildActivity = ActivityUtils.SequenceActivities(new TakeOff(self), ChildActivity);
}
ActivityUtils.RunActivity(self, ChildActivity);
return this;
}
}
}