feat(traits): add new trait Slow and Steady

Also fixes a bug with Sluggish and Snail-Paced not applying
their speed modifiers until an entity gets their movement
speed adjusted.

Content.Server/Standing/LayingDownSystem.cs

@@ -48,7 +48,7 @@ private void OnRefreshMovementSpeed(EntityUid uid, LayingDownComponent component
         if (TryComp<StandingStateComponent>(uid, out var standingState) && standingState.Standing)
             return;
 
-        args.ModifySpeed(component.DownedSpeedMultiplier, component.DownedSpeedMultiplier);
+        args.ModifySpeed(component.DownedSpeedMultiplier, component.DownedSpeedMultiplier, bypassImmunity: true);
     }
 
     private void OnParentChanged(EntityUid uid, LayingDownComponent component, EntParentChangedMessage args)

Content.Shared/Movement/Systems/MovementSpeedModifierSystem.cs

@@ -1,5 +1,6 @@
 using Content.Shared.Inventory;
 using Content.Shared.Movement.Components;
+using Content.Shared.Traits.Assorted.Components;
 using Robust.Shared.Timing;
 
 namespace Content.Shared.Movement.Systems
@@ -16,7 +17,11 @@ public void RefreshMovementSpeedModifiers(EntityUid uid, MovementSpeedModifierCo
             if (_timing.ApplyingState)
                 return;
 
-            var ev = new RefreshMovementSpeedModifiersEvent();
+            var isImmune = false;
+            if (HasComp<SpeedModifierImmunityComponent>(uid))
+                isImmune = true;
+
+            var ev = new RefreshMovementSpeedModifiersEvent(isImmune);
             RaiseLocalEvent(uid, ev);
 
             if (MathHelper.CloseTo(ev.WalkSpeedModifier, move.WalkSpeedModifier) &&
@@ -64,10 +69,24 @@ public sealed class RefreshMovementSpeedModifiersEvent : EntityEventArgs, IInven
         public float WalkSpeedModifier { get; private set; } = 1.0f;
         public float SprintSpeedModifier { get; private set; } = 1.0f;
 
-        public void ModifySpeed(float walk, float sprint)
+        /// <summary>
+        ///    Whether this entity is immune to most movement speed modifiers.
+        ///    Bypassable by setting bypassImmunity to true.
+        /// </summary
+        private bool IsImmune = false;
+
+        public void ModifySpeed(float walk, float sprint, bool bypassImmunity = false)
         {
+            if (IsImmune && !bypassImmunity)
+                return;
+
             WalkSpeedModifier *= walk;
             SprintSpeedModifier *= sprint;
         }
+
+        public RefreshMovementSpeedModifiersEvent(bool isImmune = false)
+        {
+            IsImmune = isImmune;
+        }
     }
 }

Content.Shared/Traits/Assorted/Components/SlipImmunityComponent.cs

@@ -0,0 +1,11 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Traits.Assorted.Components;
+
+/// <summary>
+///   This is used for traits that make an entity immune to slips
+/// </summary>
+[RegisterComponent, NetworkedComponent]
+public sealed partial class SlipImmunityComponent : Component
+{
+}

Content.Shared/Traits/Assorted/Components/SpeedModifierImmunityComponent.cs

@@ -0,0 +1,12 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Traits.Assorted.Components;
+
+/// <summary>
+///   This is used to make an entity's movement speed constant and
+///   never affected by almost all movement speed modifiers.
+/// </summary>
+[RegisterComponent, NetworkedComponent]
+public sealed partial class SpeedModifierImmunityComponent : Component
+{
+}

Content.Server/Traits/Assorted/TraitSpeedModifierComponent.cs → Content.Shared/Traits/Assorted/Components/TraitSpeedModifierComponent.cs

@@ -1,14 +1,16 @@
-namespace Content.Server.Traits.Assorted;
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Traits.Assorted.Components;
 
 /// <summary>
 ///  This component is used for traits that modify movement speed.
 /// </summary>
-[RegisterComponent]
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
 public sealed partial class TraitSpeedModifierComponent : Component
 {
-    [DataField(required: true)]
+    [DataField, AutoNetworkedField]
     public float WalkModifier = 1.0f;
 
-    [DataField(required: true)]
+    [DataField, AutoNetworkedField]
     public float SprintModifier = 1.0f;
 }

Content.Shared/Traits/Assorted/Systems/SlipImmunitySystem.cs

@@ -0,0 +1,19 @@
+using Content.Shared.Slippery;
+using Content.Shared.Traits.Assorted.Components;
+
+namespace Content.Shared.Traits.Assorted.Systems;
+
+public sealed class SlipImmunitySystem : EntitySystem
+{
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<SlipImmunityComponent, SlipAttemptEvent>(OnSlipAttempt);
+    }
+
+    private void OnSlipAttempt(EntityUid uid, SlipImmunityComponent component, ref SlipAttemptEvent args)
+    {
+        args.Cancel();
+    }
+}

Content.Shared/Traits/Assorted/Systems/TraitSpeedModifierSystem.cs

@@ -0,0 +1,31 @@
+using Content.Shared.Movement.Components;
+using Content.Shared.Movement.Systems;
+using Content.Shared.Traits.Assorted.Components;
+
+namespace Content.Shared.Traits.Assorted.Systems;
+
+public sealed class TraitSpeedModifierSystem : EntitySystem
+{
+    [Dependency] private readonly MovementSpeedModifierSystem _movement = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<TraitSpeedModifierComponent, ComponentStartup>(OnStartup);
+        SubscribeLocalEvent<TraitSpeedModifierComponent, RefreshMovementSpeedModifiersEvent>(OnRefreshMovementSpeed);
+    }
+
+    private void OnRefreshMovementSpeed(EntityUid uid, TraitSpeedModifierComponent component, RefreshMovementSpeedModifiersEvent args)
+    {
+        args.ModifySpeed(component.WalkModifier, component.SprintModifier, bypassImmunity: true);
+    }
+
+    private void OnStartup(EntityUid uid, TraitSpeedModifierComponent component, ComponentStartup args)
+    {
+        if (!TryComp<MovementSpeedModifierComponent>(uid, out var move))
+            return;
+
+        _movement.RefreshMovementSpeedModifiers(uid, move);
+    }
+}

Resources/Locale/en-US/traits/traits.ftl

@@ -122,3 +122,9 @@ trait-name-WeaponsGeneralist = Weapons Generalist
 trait-description-WeaponsGeneralist =
     You are a jack of all trades with melee weapons, enabling you to be versatile with your weapon arsenal.
     Your melee damage bonus for all Brute damage types (Blunt, Slash, Piercing) becomes 25%.
+
+trait-name-SlowAndSteady = Slow And Steady
+trait-description-SlowAndSteady =
+    "Slow and steady wins the race."
+    Your movement speed is decreased by [color=yellow]25%[/color].
+    You gain [color=skyblue]slip immunity[/color], [color=skyblue]slow immunity[/color] (except lying down), and [color=skyblue]speed boost immunity[/color].

Resources/Prototypes/Traits/disabilities.yml

@@ -105,6 +105,7 @@
       traits:
         - ParkourTraining
         - SnailPaced
+        - SlowAndSteady
   components:
     - type: TraitSpeedModifier
       sprintModifier: 0.85
@@ -124,6 +125,7 @@
       traits:
         - ParkourTraining
         - Sluggish
+        - SlowAndSteady
   components:
     - type: TraitSpeedModifier
       sprintModifier: 0.7

Resources/Prototypes/Traits/species.yml

@@ -60,3 +60,23 @@
       traits:
         - Swashbuckler
         - Spearmaster
+
+- type: trait
+  id: SlowAndSteady
+  category: Physical
+  points: -3
+  components:
+    - type: SpeedModifierImmunity
+    - type: TraitSpeedModifier
+      sprintModifier: 0.75
+      walkModifier: 0.75
+    - type: SlipImmunity
+  requirements:
+    - !type:CharacterSpeciesRequirement
+      species:
+        - Diona
+    - !type:CharacterTraitRequirement
+      inverted: true
+      traits:
+        - Sluggish
+        - SnailPaced