Pathfinding fixes:

- determining if a character is close enough to a waypoint works now, even if the character is too short for its collider to overlap with the wp (e.g. crawlers)
- enemies can drop down from platforms
- an extra waypoint is placed at the middle of stairs to prevent characters from choosing a waypoint on a platform above the stairs as the starting point of their path

Subsurface/Source/Characters/AI/EnemyAIController.cs

@@ -110,7 +110,21 @@ namespace Barotrauma
         {
             UpdateDistanceAccumulator();
 
-            Character.AnimController.IgnorePlatforms = (-Character.AnimController.TargetMovement.Y > Math.Abs(Character.AnimController.TargetMovement.X));
+            bool ignorePlatforms = (-Character.AnimController.TargetMovement.Y > Math.Abs(Character.AnimController.TargetMovement.X));
+
+            if (steeringManager is IndoorsSteeringManager)
+            {
+                var currPath = ((IndoorsSteeringManager)steeringManager).CurrentPath;
+                if (currPath != null && currPath.CurrentNode != null)
+                {
+                    if (currPath.CurrentNode.SimPosition.Y < Character.AnimController.GetColliderBottom().Y)
+                    {
+                        ignorePlatforms = true;
+                    }
+                }
+            }
+            
+            Character.AnimController.IgnorePlatforms = ignorePlatforms;
 
             if (Character.AnimController is HumanoidAnimController)
             {
@@ -501,13 +515,42 @@ namespace Barotrauma
                 }
 
                 spriteBatch.DrawString(GUI.Font, targetValue.ToString(), pos - Vector2.UnitY*20.0f, Color.Red);
+            }
 
+            if (selectedAiTarget != null)
+            {
+                GUI.DrawLine(spriteBatch,
+                    new Vector2(Character.DrawPosition.X, -Character.DrawPosition.Y),
+                    new Vector2(selectedAiTarget.WorldPosition.X, -selectedAiTarget.WorldPosition.Y), Color.Red);
             }
 
             spriteBatch.DrawString(GUI.Font, targetValue.ToString(), pos - Vector2.UnitY * 80.0f, Color.Red);
 
             spriteBatch.DrawString(GUI.Font, "updatetargets: "+updateTargetsTimer, pos - Vector2.UnitY * 100.0f, Color.Red);
             spriteBatch.DrawString(GUI.Font, "cooldown: " + coolDownTimer, pos - Vector2.UnitY * 120.0f, Color.Red);
+
+
+            IndoorsSteeringManager pathSteering = steeringManager as IndoorsSteeringManager;
+            if (pathSteering == null || pathSteering.CurrentPath == null || pathSteering.CurrentPath.CurrentNode == null) return;
+
+            GUI.DrawLine(spriteBatch,
+                new Vector2(Character.DrawPosition.X, -Character.DrawPosition.Y),
+                new Vector2(pathSteering.CurrentPath.CurrentNode.DrawPosition.X, -pathSteering.CurrentPath.CurrentNode.DrawPosition.Y),
+                Color.LightGreen);
+
+
+            for (int i = 1; i < pathSteering.CurrentPath.Nodes.Count; i++)
+            {
+                GUI.DrawLine(spriteBatch,
+                    new Vector2(pathSteering.CurrentPath.Nodes[i].DrawPosition.X, -pathSteering.CurrentPath.Nodes[i].DrawPosition.Y),
+                    new Vector2(pathSteering.CurrentPath.Nodes[i - 1].DrawPosition.X, -pathSteering.CurrentPath.Nodes[i - 1].DrawPosition.Y),
+                    Color.LightGreen);
+
+                spriteBatch.DrawString(GUI.SmallFont,
+                    pathSteering.CurrentPath.Nodes[i].ID.ToString(),
+                    new Vector2(pathSteering.CurrentPath.Nodes[i].DrawPosition.X, -pathSteering.CurrentPath.Nodes[i].DrawPosition.Y - 10),
+                    Color.LightGreen);
+            }
         }
 
         public override void FillNetworkData(NetBuffer message)

Subsurface/Source/Characters/AI/IndoorsSteeringManager.cs

@@ -146,9 +146,11 @@ namespace Barotrauma
             }
 
             var collider = character.AnimController.Collider;
+            Vector2 colliderBottom = character.AnimController.GetColliderBottom();
 
             if (Math.Abs(collider.SimPosition.X - currentPath.CurrentNode.SimPosition.X) < collider.radius * 2 &&
-                Math.Abs(collider.SimPosition.Y - currentPath.CurrentNode.SimPosition.Y) < collider.height / 2 + collider.radius)
+                currentPath.CurrentNode.SimPosition.Y > colliderBottom.Y &&
+                currentPath.CurrentNode.SimPosition.Y < colliderBottom.Y + 1.5f)
             {
                 currentPath.SkipToNextNode();
             }

Subsurface/Source/Characters/Animation/FishAnimController.cs

@@ -225,9 +225,7 @@ namespace Barotrauma
         {
             movement = MathUtils.SmoothStep(movement, TargetMovement * walkSpeed, 0.2f);
             if (movement == Vector2.Zero) return;
-
+            
-            IgnorePlatforms = (TargetMovement.Y < -Math.Abs(TargetMovement.X));
-
             float mainLimbHeight, mainLimbAngle;
             if (MainLimb.type == LimbType.Torso)
             {

Subsurface/Source/Map/WayPoint.cs

@@ -444,7 +444,7 @@ namespace Barotrauma
 
             foreach (Structure stairs in stairList)
             {
-                WayPoint[] stairPoints = new WayPoint[2];
+                WayPoint[] stairPoints = new WayPoint[3];
 
                 stairPoints[0] = new WayPoint(
                     new Vector2(stairs.Rect.X - 32.0f,
@@ -463,8 +463,10 @@ namespace Barotrauma
                         stairPoints[i].ConnectTo(closest);
                     }                    
                 }
-
+                
-                stairPoints[0].ConnectTo(stairPoints[1]);                
+                stairPoints[2] = new WayPoint((stairPoints[0].Position + stairPoints[1].Position)/2, SpawnType.Path, submarine);
+                stairPoints[0].ConnectTo(stairPoints[2]);
+                stairPoints[2].ConnectTo(stairPoints[1]);
             }
 
             foreach (Item item in Item.ItemList)