NPC refactor (#10122)

Co-authored-by: metalgearsloth <metalgearsloth@gmail.com>

Content.Server/NPC/Systems/NPCSteeringSystem.Avoidance.cs

@@ -0,0 +1,44 @@
+using System.Linq;
+using Content.Server.NPC.Components;
+using Content.Shared.CCVar;
+using Content.Shared.Movement.Components;
+using Robust.Shared.Collections;
+using Robust.Shared.Configuration;
+using Robust.Shared.Physics;
+using Robust.Shared.Physics.Collision.Shapes;
+
+namespace Content.Server.NPC.Systems;
+
+public sealed partial class NPCSteeringSystem
+{
+    // TODO
+
+    // Derived from RVO2 library which uses ORCA (optimal reciprocal collision avoidance).
+    // Could also potentially use something force based or RVO or detour crowd.
+
+    public bool CollisionAvoidanceEnabled { get; set; } = true;
+
+    public bool ObstacleAvoidanceEnabled { get; set; } = true;
+
+    private const float Radius = 0.35f;
+    private const float RVO_EPSILON = 0.00001f;
+
+    private void InitializeAvoidance()
+    {
+        var configManager = IoCManager.Resolve<IConfigurationManager>();
+        configManager.OnValueChanged(CCVars.NPCCollisionAvoidance, SetCollisionAvoidance);
+    }
+
+    private void ShutdownAvoidance()
+    {
+        var configManager = IoCManager.Resolve<IConfigurationManager>();
+        configManager.UnsubValueChanged(CCVars.NPCCollisionAvoidance, SetCollisionAvoidance);
+    }
+
+    // I deleted all of my relevant code for now as I only had dynamic body avoidance working and not static
+    // but it will be added back real soon.
+    private void SetCollisionAvoidance(bool obj)
+    {
+        CollisionAvoidanceEnabled = obj;
+    }
+}