Add ImpactOrientation to WarheadArgs

Allows to pass the horizontal facing/yaw
and vertical angle/pitch of the carrier
projectile to warheads for further use.

Add ImpactPosition to WarheadArgs

InflictDamage doesn't pass the impact pos
directly, and the very point of WarheadArgs
is to avoid adding more and more arguments
to the warhead methods.

OpenRA.Game/GameRules/WeaponInfo.cs

@@ -38,6 +38,8 @@ namespace OpenRA.GameRules
 		public WeaponInfo Weapon;
 		public int[] DamageModifiers = { };
 		public WPos? Source;
+		public WRot ImpactOrientation;
+		public WPos ImpactPosition;
 		public Actor SourceActor;
 		public Target WeaponTarget;
 
@@ -45,6 +47,7 @@ namespace OpenRA.GameRules
 		{
 			Weapon = args.Weapon;
 			DamageModifiers = args.DamageModifiers;
+			ImpactPosition = args.PassiveTarget;
 			Source = args.Source;
 			SourceActor = args.SourceActor;
 			WeaponTarget = args.GuidedTarget;

OpenRA.Mods.Common/Projectiles/AreaBeam.cs

@@ -237,6 +237,12 @@ namespace OpenRA.Mods.Common.Projectiles
 
 					var warheadArgs = new WarheadArgs(args)
 					{
+						ImpactOrientation = new WRot(WAngle.Zero, Util.GetVerticalAngle(args.Source, target), args.CurrentMuzzleFacing()),
+
+						// Calculating an impact position is bogus for line damage.
+						// FindActorsOnLine guarantees that the beam touches the target's HitShape,
+						// so we just assume a center hit to avoid bogus warhead recalculations.
+						ImpactPosition = a.CenterPosition,
 						DamageModifiers = adjustedModifiers.ToArray(),
 					};
 

OpenRA.Mods.Common/Projectiles/Bullet.cs

@@ -122,7 +122,7 @@ namespace OpenRA.Mods.Common.Projectiles
 		ContrailRenderable contrail;
 
 		[Sync]
-		WPos pos, target, source;
+		WPos pos, lastPos, target, source;
 
 		int length;
 		int ticks, smokeTicks;
@@ -200,7 +200,7 @@ namespace OpenRA.Mods.Common.Projectiles
 			if (anim != null)
 				anim.Tick();
 
-			var lastPos = pos;
+			lastPos = pos;
 			pos = WPos.LerpQuadratic(source, target, angle, ticks, length);
 
 			// Check for walls or other blocking obstacles
@@ -287,7 +287,13 @@ namespace OpenRA.Mods.Common.Projectiles
 
 			world.AddFrameEndTask(w => w.Remove(this));
 
-			args.Weapon.Impact(Target.FromPos(pos), new WarheadArgs(args));
+			var warheadArgs = new WarheadArgs(args)
+			{
+				ImpactOrientation = new WRot(WAngle.Zero, Util.GetVerticalAngle(lastPos, pos), args.Facing),
+				ImpactPosition = pos,
+			};
+
+			args.Weapon.Impact(Target.FromPos(pos), warheadArgs);
 		}
 
 		bool AnyValidTargetsInRadius(World world, WPos pos, WDist radius, Actor firedBy, bool checkTargetType)

OpenRA.Mods.Common/Projectiles/GravityBomb.cs

@@ -12,6 +12,7 @@
 using System.Collections.Generic;
 using OpenRA.GameRules;
 using OpenRA.Graphics;
+using OpenRA.Primitives;
 using OpenRA.Traits;
 
 namespace OpenRA.Mods.Common.Projectiles
@@ -58,7 +59,7 @@ namespace OpenRA.Mods.Common.Projectiles
 		WVec velocity;
 
 		[Sync]
-		WPos pos;
+		WPos pos, lastPos;
 
 		public GravityBomb(GravityBombInfo info, ProjectileArgs args)
 		{
@@ -82,6 +83,7 @@ namespace OpenRA.Mods.Common.Projectiles
 
 		public void Tick(World world)
 		{
+			lastPos = pos;
 			pos += velocity;
 			velocity += acceleration;
 
@@ -90,7 +92,13 @@ namespace OpenRA.Mods.Common.Projectiles
 				pos += new WVec(0, 0, args.PassiveTarget.Z - pos.Z);
 				world.AddFrameEndTask(w => w.Remove(this));
 
-				args.Weapon.Impact(Target.FromPos(pos), new WarheadArgs(args));
+				var warheadArgs = new WarheadArgs(args)
+				{
+					ImpactOrientation = new WRot(WAngle.Zero, Util.GetVerticalAngle(lastPos, pos), args.Facing),
+					ImpactPosition = pos,
+				};
+
+				args.Weapon.Impact(Target.FromPos(pos), warheadArgs);
 			}
 
 			if (anim != null)

OpenRA.Mods.Common/Projectiles/InstantHit.cs

@@ -81,7 +81,13 @@ namespace OpenRA.Mods.Common.Projectiles
 					target = Target.FromPos(blockedPos);
 			}
 
-			args.Weapon.Impact(target, new WarheadArgs(args));
+			var warheadArgs = new WarheadArgs(args)
+			{
+				ImpactOrientation = new WRot(WAngle.Zero, Util.GetVerticalAngle(args.Source, target.CenterPosition), args.Facing),
+				ImpactPosition = target.CenterPosition,
+			};
+
+			args.Weapon.Impact(target, warheadArgs);
 			world.AddFrameEndTask(w => w.Remove(this));
 		}
 

OpenRA.Mods.Common/Projectiles/LaserZap.cs

@@ -168,7 +168,13 @@ namespace OpenRA.Mods.Common.Projectiles
 
 			if (ticks < info.DamageDuration && --interval <= 0)
 			{
-				args.Weapon.Impact(Target.FromPos(target), new WarheadArgs(args));
+				var warheadArgs = new WarheadArgs(args)
+				{
+					ImpactOrientation = new WRot(WAngle.Zero, Util.GetVerticalAngle(source, target), args.CurrentMuzzleFacing()),
+					ImpactPosition = target,
+				};
+
+				args.Weapon.Impact(Target.FromPos(target), warheadArgs);
 				interval = info.DamageInterval;
 			}
 

OpenRA.Mods.Common/Projectiles/Missile.cs

@@ -895,7 +895,13 @@ namespace OpenRA.Mods.Common.Projectiles
 			if (ticks <= info.Arm)
 				return;
 
-			args.Weapon.Impact(Target.FromPos(pos), new WarheadArgs(args));
+			var warheadArgs = new WarheadArgs(args)
+			{
+				ImpactOrientation = new WRot(WAngle.Zero, WAngle.FromFacing(vFacing), WAngle.FromFacing(hFacing)),
+				ImpactPosition = pos,
+			};
+
+			args.Weapon.Impact(Target.FromPos(pos), warheadArgs);
 		}
 
 		public IEnumerable<IRenderable> Render(WorldRenderer wr)

OpenRA.Mods.Common/Projectiles/Railgun.cs

@@ -199,12 +199,32 @@ namespace OpenRA.Mods.Common.Projectiles
 					animationComplete = true;
 
 				if (!info.DamageActorsInLine)
-					args.Weapon.Impact(Target.FromPos(target), new WarheadArgs(args));
+				{
+					var warheadArgs = new WarheadArgs(args)
+					{
+						ImpactOrientation = new WRot(WAngle.Zero, Util.GetVerticalAngle(args.Source, target), args.Facing),
+						ImpactPosition = target,
+					};
+
+					args.Weapon.Impact(Target.FromPos(target), warheadArgs);
+				}
 				else
 				{
 					var actors = world.FindActorsOnLine(args.Source, target, info.BeamWidth);
 					foreach (var a in actors)
-						args.Weapon.Impact(Target.FromActor(a), new WarheadArgs(args));
+					{
+						var warheadArgs = new WarheadArgs(args)
+						{
+							ImpactOrientation = new WRot(WAngle.Zero, Util.GetVerticalAngle(args.Source, target), args.Facing),
+
+							// Calculating an impact position is bogus for line damage.
+							// FindActorsOnLine guarantees that the beam touches the target's HitShape,
+							// so we just assume a center hit to avoid bogus warhead recalculations.
+							ImpactPosition = a.CenterPosition,
+						};
+
+						args.Weapon.Impact(Target.FromActor(a), warheadArgs);
+					}
 				}
 			}
 

OpenRA.Mods.Common/Util.cs

@@ -108,6 +108,15 @@ namespace OpenRA.Mods.Common
 			return WPos.Lerp(fromPos, toPos, 1, 2);
 		}
 
+		public static WAngle GetVerticalAngle(WPos source, WPos target)
+		{
+			var delta = target - source;
+			var horizontalDelta = delta.HorizontalLength;
+			var verticalVector = new WVec(-delta.Z, -horizontalDelta, 0);
+
+			return verticalVector.Yaw;
+		}
+
 		public static IEnumerable<T> Shuffle<T>(this IEnumerable<T> ts, MersenneTwister random)
 		{
 			// Fisher-Yates