Improvements to Mobile to support smooth movement (like real-ra does it)

- McvDeploy got simpler.
    - BUGFIX: Bullet no longer crashes when it damages a tree

OpenRa.Game/Bullet.cs

@@ -84,6 +84,9 @@ namespace OpenRa.Game
 
 		float GetDamageToInflict(Actor target)
 		{
+			if( target.unitInfo == null ) // tree or other doodad
+				return 0;
+
 			/* todo: some things can't be damaged AT ALL by certain weapons! */
 			var distance = (target.CenterLocation - Dest).Length;
 			var rawDamage = Weapon.Damage * (float)Math.Exp(-distance / Warhead.Spread);

OpenRa.Game/MoveOrder.cs

@@ -31,31 +31,9 @@ namespace OpenRa.Game
 			if (leftMouseButton) return;
 			
 			if (Game.LocalPlayer == Unit.Owner)
-				Game.PlaySound(Game.SovietVoices.First.GetNext() + GetVoiceSuffix(), false);
-
+				Game.PlaySound("ackno.r00", false);
 			var mobile = Unit.traits.Get<Traits.Mobile>();
-			mobile.destination = Destination;
-			mobile.desiredFacing = null;
-		}
-	}
-
-	class DeployMcvOrder : Order
-	{
-		Actor Unit;
-		int2 Location;
-
-		public DeployMcvOrder( Actor unit, int2 location )
-		{
-			Unit = unit;
-			Location = location;
-		}
-
-		public override void Apply( bool leftMouseButton )
-		{
-			if (leftMouseButton) return;
-			Unit.traits.Get<Traits.McvDeploy>().DeployLocation = Location;
-			var mobile = Unit.traits.Get<Traits.Mobile>();
-			mobile.destination = mobile.toCell;
+			mobile.SetNextAction( new Traits.Mobile.MoveTo( Destination ) );
 		}
 	}
 }

OpenRa.Game/Traits/McvDeploy.cs

@@ -5,37 +5,45 @@ using System.Text;
 
 namespace OpenRa.Game.Traits
 {
-	class McvDeploy : IOrder, ITick
+	class McvDeploy : IOrder
 	{
-		public int2? DeployLocation;
-
 		public McvDeploy(Actor self)
 		{
 		}
 
 		public Order Order(Actor self, int2 xy)
 		{
-			DeployLocation = null;
 			// TODO: check that there's enough space at the destination.
 			if( xy == self.Location )
 				return new DeployMcvOrder( self, xy );
 
 			return null;
 		}
+	}
 
-		public void Tick(Actor self)
+	class DeployMcvOrder : Order
 	{
-			if( self.Location != DeployLocation )
-				return;
+		Actor Unit;
+		int2 Location;
 
-			var mobile = self.traits.Get<Mobile>();
-			mobile.desiredFacing = 96;
-			if( mobile.moveFraction < mobile.moveFractionTotal )
-				return;
+		public DeployMcvOrder( Actor unit, int2 location )
+		{
+			Unit = unit;
+			Location = location;
+		}
 
-			if( mobile.facing != mobile.desiredFacing )
-				return;
+		public override void Apply( bool leftMouseButton )
+		{
+			if( leftMouseButton ) return;
+			Unit.traits.Get<Mobile>().SetNextAction( new Mobile.Turn( 96 ) { NextAction = new DeployAction() } );
+		}
 
+		class DeployAction : Mobile.CurrentAction
+		{
+			public Mobile.CurrentAction NextAction { get; set; }
+
+			public void Tick( Actor self, Mobile mobile )
+			{
 				Game.world.AddFrameEndTask( _ =>
 				{
 					Game.world.Remove( self );
@@ -44,3 +52,4 @@ namespace OpenRa.Game.Traits
 			}
 		}
 	}
+}

OpenRa.Game/Traits/Mobile.cs

@@ -11,66 +11,33 @@ namespace OpenRa.Game.Traits
 	{
 		public Actor self;
 
-		public int2 fromCell, destination;
-		public int2 toCell { get { return self.Location; } }
-		public int moveFraction, moveFractionTotal;
+		public int2 fromCell;
+		public int2 toCell { get { return self.Location; } set { self.Location = value; } }
 		public int facing;
-		public int? desiredFacing;
+
 		public int Voice = Game.CosmeticRandom.Next(2);
+		CurrentAction currentAction;
 
 		public Mobile(Actor self)
 		{
 			this.self = self;
-			fromCell = destination = self.Location;
+			fromCell = toCell;
 		}
 
-		void UpdateCenterLocation()
+		public void SetNextAction( CurrentAction nextAction )
 		{
-			float fraction = (moveFraction > 0) ? (float)moveFraction / moveFractionTotal : 0f;
-			self.CenterLocation = new float2(12, 12) + Game.CellSize * float2.Lerp(fromCell, toCell, fraction);
+			if( currentAction == null )
+				currentAction = nextAction;
+			else
+				currentAction.NextAction = nextAction;
 		}
 
 		public void Tick(Actor self)
 		{
-			Move(self);
-			UpdateCenterLocation();
-		}
-
-		void Move(Actor self)
-		{
-			if( fromCell != toCell )
-				desiredFacing = Util.GetFacing( toCell - fromCell, facing );
-
-			if( desiredFacing != null && desiredFacing != facing )
-			{
-				Util.TickFacing( ref facing, desiredFacing.Value, self.unitInfo.ROT );
-				return;
-			}
-			desiredFacing = null;
-
-			if( fromCell != toCell )
-				moveFraction += ((UnitInfo.MobileInfo)self.unitInfo).Speed;
-
-			if (moveFraction < moveFractionTotal)
-				return;
-
-			moveFraction = 0;
-			moveFractionTotal = 0;
-			fromCell = toCell;
-
-			if (destination == toCell)
-				return;
-
-			List<int2> res = Game.pathFinder.FindUnitPath(toCell, PathFinder.DefaultEstimator(destination));
-			if (res.Count != 0)
-			{
-				self.Location = res[res.Count - 1];
-
-				int2 dir = toCell - fromCell;
-				moveFractionTotal = (dir.X != 0 && dir.Y != 0) ? 70 : 50;
-			}
+			if( currentAction != null )
+				currentAction.Tick( self, this );
 			else
-				destination = toCell;
+				fromCell = toCell;
 		}
 
 		public Order Order(Actor self, int2 xy)
@@ -80,5 +47,135 @@ namespace OpenRa.Game.Traits
 
 			return null;
 		}
+
+	
+		public interface CurrentAction
+		{
+			CurrentAction NextAction { set; }
+			void Tick( Actor self, Mobile mobile );
+		}
+
+		public class Turn : CurrentAction
+		{
+			public CurrentAction NextAction { get; set; }
+
+			public readonly int desiredFacing;
+
+			public Turn( int desiredFacing )
+			{
+				this.desiredFacing = desiredFacing;
+			}
+
+			public void Tick( Actor self, Mobile mobile )
+			{
+				if( desiredFacing == mobile.facing )
+				{
+					mobile.currentAction = NextAction;
+					if( NextAction != null )
+						NextAction.Tick( self, mobile );
+					return;
+				}
+				Util.TickFacing( ref mobile.facing, desiredFacing, self.unitInfo.ROT );
+			}
+		}
+
+		public class MoveTo : CurrentAction
+		{
+			public CurrentAction NextAction { get; set; }
+
+			int2 destination;
+			List<int2> path;
+
+			int moveFraction, moveFractionTotal;
+			float2 from, to;
+
+			Action<Actor, Mobile> OnComplete;
+
+			public MoveTo( int2 destination )
+			{
+				this.destination = destination;
+			}
+
+			public void Tick( Actor self, Mobile mobile )
+			{
+				if( moveFractionTotal != 0 )
+				{
+					TickMove( self, mobile );
+					return;
+				}
+
+				if( destination == self.Location )
+				{
+					mobile.currentAction = NextAction;
+					return;
+				}
+
+				if( path == null )
+					path = Game.pathFinder.FindUnitPath( self.Location, PathFinder.DefaultEstimator( destination ) );
+				if( path.Count == 0 )
+				{
+					destination = mobile.toCell;
+					return;
+				}
+
+				var nextCell = path[ path.Count - 1 ];
+				int2 dir = nextCell - mobile.fromCell;
+				var firstFacing = Util.GetFacing( dir, mobile.facing );
+				if( firstFacing != mobile.facing )
+					mobile.currentAction = new Turn( firstFacing ) { NextAction = this };
+				else
+				{
+					mobile.toCell = nextCell;
+					path.RemoveAt( path.Count - 1 );
+					moveFractionTotal = ( dir.X != 0 && dir.Y != 0 ) ? 35 : 25;
+					from = CenterOfCell( mobile.fromCell );
+					to = BetweenCells( mobile.fromCell, mobile.toCell );
+					OnComplete = OnCompleteFirstHalf;
+				}
+				mobile.currentAction.Tick( self, mobile );
+			}
+
+			void TickMove( Actor self, Mobile mobile )
+			{
+				moveFraction += ( self.unitInfo as UnitInfo.MobileInfo ).Speed;
+				UpdateCenterLocation( self, (float)moveFraction / moveFractionTotal, from, to );
+				if( moveFraction >= moveFractionTotal )
+				{
+					moveFraction -= moveFractionTotal;
+					OnComplete( self, mobile );
+					mobile.fromCell = mobile.toCell;
+				}
+				return;
+			}
+
+			static void UpdateCenterLocation( Actor self, float frac, float2 from, float2 to )
+			{
+				self.CenterLocation = float2.Lerp( from, to, frac );
+			}
+
+			static float2 CenterOfCell( int2 loc )
+			{
+				return new float2( 12, 12 ) + Game.CellSize * (float2)loc;
+			}
+
+			static float2 BetweenCells( int2 from, int2 to )
+			{
+				return 0.5f * ( CenterOfCell( from ) + CenterOfCell( to ) );
+			}
+
+			void OnCompleteFirstHalf( Actor self, Mobile mobile )
+			{
+				from = BetweenCells( mobile.fromCell, mobile.toCell );
+				to = CenterOfCell( mobile.toCell );
+				OnComplete = OnCompleteSecondHalf;
+			}
+
+			void OnCompleteSecondHalf( Actor self, Mobile mobile )
+			{
+				moveFractionTotal = 0;
+				self.CenterLocation = CenterOfCell( mobile.toCell );
+				OnComplete = null;
+			}
+		}
 	}
 }

OpenRa.Game/Traits/RenderUnit.cs

@@ -23,10 +23,7 @@ namespace OpenRa.Game.Traits
 
 		public override IEnumerable<Pair<Sprite, float2>> Render(Actor self)
 		{
-			var mobile = self.traits.Get<Mobile>();
-			float fraction = (mobile.moveFraction > 0) ? (float)mobile.moveFraction / mobile.moveFractionTotal : 0f;
-			var centerLocation = new float2(12, 12) + Game.CellSize * float2.Lerp(mobile.fromCell, mobile.toCell, fraction);
-			yield return Centered(anim.Image, centerLocation);
+			yield return Centered( anim.Image, self.CenterLocation );
 		}
 	}
 }