From dd3f8f5c8c5535383571cd22b3e650fd581a8127 Mon Sep 17 00:00:00 2001
From: gmriggs <gmriggs@gmail.com>
Date: Tue, 18 May 2021 22:37:09 -0400
Subject: [PATCH] add option to enable constraint manager on server

---
 Source/ACE.Server/Managers/PropertyManager.cs        |  1 +
 .../ACE.Server/Physics/Managers/ConstraintManager.cs |  4 ++--
 Source/ACE.Server/Physics/PhysicsObj.cs              | 12 ++++++++++--
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/Source/ACE.Server/Managers/PropertyManager.cs b/Source/ACE.Server/Managers/PropertyManager.cs
index ffcb03822e..e484eb57c3 100644
--- a/Source/ACE.Server/Managers/PropertyManager.cs
+++ b/Source/ACE.Server/Managers/PropertyManager.cs
@@ -593,6 +593,7 @@ public static void LoadDefaultProperties()
                 ("trajectory_alt_solver", new Property<bool>(false, "use the alternate trajectory solver for missiles and spell projectiles")),
                 ("universal_masteries", new Property<bool>(true, "if TRUE, matches end of retail masteries - players wielding almost any weapon get +5 DR, except if the weapon \"seems tough to master\". " +
                                                                  "if FALSE, players start with mastery of 1 melee and 1 ranged weapon type based on heritage, and can later re-select these 2 masteries")),
+                ("use_constraint_manager", new Property<bool>(false, "enables the constraint manager on the server, which can mitigate some of the desyncs between the client and server movement methods")),
                 ("use_generator_rotation_offset", new Property<bool>(true, "enables or disables using the generator's current rotation when offseting relative positions")),
                 ("use_turbine_chat", new Property<bool>(true, "enables or disables global chat channels (General, LFG, Roleplay, Trade, Olthoi, Society, Allegience)")),
                 ("use_wield_requirements", new Property<bool>(true, "disable this to bypass wield requirements. mostly for dev debugging")),
diff --git a/Source/ACE.Server/Physics/Managers/ConstraintManager.cs b/Source/ACE.Server/Physics/Managers/ConstraintManager.cs
index 7188b79055..43fec75d8d 100644
--- a/Source/ACE.Server/Physics/Managers/ConstraintManager.cs
+++ b/Source/ACE.Server/Physics/Managers/ConstraintManager.cs
@@ -36,7 +36,7 @@ public void ConstrainTo(Position position, float startDistance, float maxDistanc
 
         public bool IsFullyConstrained()
         {
-            return ConstraintDistanceMax * 0.9f < ConstraintPosOffset;
+            return ConstraintPosOffset > ConstraintDistanceMax * 0.9f;
         }
 
         public void SetPhysicsObject(PhysicsObj obj)
@@ -73,7 +73,7 @@ public void adjust_offset(AFrame offset, double quantum)
                 else
                     offset.Origin = Vector3.Zero;
             }
-            ConstraintPosOffset = offset.Origin.Length();
+            ConstraintPosOffset += offset.Origin.Length();
         }
     }
 }
diff --git a/Source/ACE.Server/Physics/PhysicsObj.cs b/Source/ACE.Server/Physics/PhysicsObj.cs
index 0994b237e9..8127b92029 100644
--- a/Source/ACE.Server/Physics/PhysicsObj.cs
+++ b/Source/ACE.Server/Physics/PhysicsObj.cs
@@ -567,7 +567,7 @@ public float GetHeight()
             return PartArray.GetHeight();
         }
 
-        public double GetMaxConstraintDistance()
+        public float GetMaxConstraintDistance()
         {
             return (Position.ObjCellID & 0xFFFF) < 0x100 ? 50.0f : 20.0f;
         }
@@ -617,7 +617,7 @@ public uint GetSetupID()
             return PartArray.GetSetupID();
         }
 
-        public double GetStartConstraintDistance()
+        public float GetStartConstraintDistance()
         {
             return (Position.ObjCellID & 0xFFFF) < 0x100 ? 5.0f : 10.0f;
         }
@@ -4345,6 +4345,14 @@ public bool update_object_server_new(bool forcePos = true)
                 }
 
                 set_current_pos(RequestPos);
+
+                if (PropertyManager.GetBool("use_constraint_manager").Item)
+                {
+                    var startDist = GetStartConstraintDistance();
+                    var maxDist = GetMaxConstraintDistance();
+
+                    ConstrainTo(RequestPos, startDist, maxDist);
+                }
             }
 
             // for teleport, use SetPosition?