Add SpawnActorWarhead

OpenRA.Mods.Common/Warheads/SpawnActorWarhead.cs

@@ -0,0 +1,217 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * 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;
+using System.Collections.Generic;
+using System.Linq;
+using OpenRA.GameRules;
+using OpenRA.Mods.Common.Activities;
+using OpenRA.Mods.Common.Effects;
+using OpenRA.Mods.Common.Traits;
+using OpenRA.Primitives;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.Common.Warheads
+{
+	[Desc("Spawns actors upon detonation.")]
+	public class SpawnActorWarhead : Warhead, IRulesetLoaded<WeaponInfo>
+	{
+		[FieldLoader.Require]
+		[Desc("Actors to spawn.")]
+		public readonly string[] Actors;
+
+		[Desc("The cell range to try placing the actors within.")]
+		public readonly int Range = 10;
+
+		[Desc("Map player to give the actors to. Defaults to the attacker's owner.")]
+		public readonly string Owner;
+
+		[Desc("Should this actor link to the actor which created it?")]
+		public readonly bool LinkToParent = false;
+
+		[Desc("Should actors always be spawned on the ground?")]
+		public readonly bool ForceGround = false;
+
+		[Desc("Should actors spawn facing the same direction as the projectile?")]
+		public readonly bool SetFacing = false;
+
+		[Desc("Don't spawn actors on this terrain.")]
+		public readonly HashSet<string> InvalidTerrain = new();
+
+		[Desc("Defines the image of an optional animation played at the spawning location.")]
+		public readonly string Image;
+
+		[SequenceReference(nameof(Image), allowNullImage: true)]
+		[Desc("Defines the sequence of an optional animation played at the spawning location.")]
+		public readonly string Sequence = "idle";
+
+		[PaletteReference]
+		[Desc("Defines the palette of an optional animation played at the spawning location.")]
+		public readonly string Palette = "effect";
+
+		public readonly bool UsePlayerPalette = false;
+
+		[Desc("List of sounds that can be played at the spawning location.")]
+		public readonly string[] Sounds = Array.Empty<string>();
+
+		void IRulesetLoaded<WeaponInfo>.RulesetLoaded(Ruleset rules, WeaponInfo info)
+		{
+			foreach (var a in Actors)
+			{
+				var actorInfo = rules.Actors[a.ToLowerInvariant()];
+				var buildingInfo = actorInfo.TraitInfoOrDefault<BuildingInfo>();
+
+				if (buildingInfo != null)
+					throw new YamlException($"SpawnActorWarhead cannot be used to spawn building actor '{a}'!");
+			}
+		}
+
+		public override void DoImpact(in Target target, WarheadArgs args)
+		{
+			var firedBy = args.SourceActor;
+			if (!target.IsValidFor(firedBy))
+				return;
+
+			var world = firedBy.World;
+			var map = world.Map;
+			var pos = target.CenterPosition;
+			var targetCell = map.CellContaining(pos);
+			if (!map.Contains(targetCell))
+				return;
+
+			var directHit = false;
+			foreach (var victim in world.FindActorsOnCircle(pos, WDist.Zero))
+			{
+				if (!IsValidAgainst(victim, firedBy))
+					continue;
+
+				if (!victim.Info.HasTraitInfo<IHealthInfo>())
+					continue;
+
+				if (victim.TraitsImplementing<HitShape>()
+					.Any(i => !i.IsTraitDisabled && i.DistanceFromEdge(victim, pos).Length <= 0))
+				{
+					directHit = true;
+					break;
+				}
+			}
+
+			if (!directHit && !IsValidTarget(map.GetTerrainInfo(targetCell).TargetTypes))
+				return;
+
+			foreach (var a in Actors)
+			{
+				var td = new TypeDictionary();
+				var actorName = a.ToLowerInvariant();
+				var ai = map.Rules.Actors[actorName];
+
+				var owner = Owner == null ? firedBy.Owner : world.Players.First(p => p.InternalName == Owner);
+				td.Add(new OwnerInit(owner));
+
+				if (LinkToParent)
+					td.Add(new ParentActorInit(firedBy));
+
+				if (SetFacing)
+					td.Add(new FacingInit(args.ImpactOrientation.Yaw));
+
+				var cachedTarget = target;
+				world.AddFrameEndTask(w =>
+				{
+					var immobileInfo = ai.TraitInfoOrDefault<ImmobileInfo>();
+					if (immobileInfo != null)
+					{
+						foreach (var cell in map.FindTilesInCircle(targetCell, Range))
+						{
+							if (!InvalidTerrain.Contains(map.GetTerrainInfo(cell).Type)
+								&& (!immobileInfo.OccupiesSpace || !world.ActorMap.GetActorsAt(cell).Any()))
+							{
+								td.Add(new LocationInit(cell));
+								world.CreateActor(actorName, td);
+								PlaySoundAndEffect(w, owner, map.CenterOfCell(cell));
+								return;
+							}
+						}
+
+						return;
+					}
+
+					var unit = world.CreateActor(false, actorName, td);
+					var positionable = unit.Trait<IPositionable>();
+					foreach (var cell in map.FindTilesInCircle(targetCell, Range))
+					{
+						if (InvalidTerrain.Contains(map.GetTerrainInfo(cell).Type))
+							continue;
+
+						if (positionable is Aircraft aircraft)
+						{
+							var position = map.CenterOfCell(cell);
+							var dat = map.DistanceAboveTerrain(cachedTarget.CenterPosition);
+							var isAtGroundLevel = ForceGround || dat.Length <= 0;
+							if (isAtGroundLevel)
+							{
+								if (aircraft.Info.CanEnterCell(world, unit, cell))
+									positionable.SetPosition(unit, position);
+								else
+									continue;
+							}
+							else
+							{
+								position = new WPos(position.X, position.Y, Math.Max(position.Z, dat.Length));
+								positionable.SetPosition(unit, position);
+								unit.QueueActivity(new FlyIdle(unit));
+							}
+
+							PlaySoundAndEffect(w, owner, position);
+							w.Add(unit);
+							return;
+						}
+						else
+						{
+							var subCell = positionable.GetAvailableSubCell(cell);
+							if (subCell != SubCell.Invalid)
+							{
+								positionable.SetPosition(unit, cell, subCell);
+								var position = positionable.CenterPosition;
+								if (positionable is Mobile mobile)
+								{
+									var dat = map.DistanceAboveTerrain(cachedTarget.CenterPosition);
+									if (!ForceGround && dat.Length > 0)
+									{
+										positionable.SetCenterPosition(unit,
+											new WPos(position.X, position.Y, Math.Max(position.Z, dat.Length)));
+
+										unit.QueueActivity(mobile.ReturnToCell(unit));
+									}
+								}
+
+								PlaySoundAndEffect(w, owner, position);
+								w.Add(unit);
+								return;
+							}
+						}
+					}
+
+					unit.Dispose();
+				});
+			}
+		}
+
+		void PlaySoundAndEffect(World w, Player owner, WPos pos)
+		{
+			if (Image != null)
+				w.Add(new SpriteEffect(pos, w, Image, Sequence, UsePlayerPalette ? Palette + owner.InternalName : Palette));
+
+			var sound = Sounds.RandomOrDefault(Game.CosmeticRandom);
+			if (sound != null)
+				Game.Sound.Play(SoundType.World, sound, pos);
+		}
+	}
+}