ModernUO/Projects/UOContent/Spells/Ninjitsu/MirrorImage.cs
Kamron Batman e07416902a
feat: derive the Running bit from the step pace and fix step-pacing bursts (#2599)
Stacked on #2594. Fixes jerky creature movement (lich / Fast-bucket melee chases) by choosing the client animation flag from the actual step pace instead of a caller-supplied `run` argument, and fixes three step-pacing defects in the move budget found while verifying it with paired server/client traces.

### Why

The `Direction.Running` bit does nothing for creatures server-side (`Mobile.OnMove` reads it only for the player throttle and stealth reveal). Its whole effect is on the client, which animates each step over a fixed time selected by that bit: walk 400 ms / run 200 ms on foot, 200 / 100 ms mounted. ClassicUO queues up to 5 steps and *drops* the sixth, so a creature stepping every 300 ms while flagged as walking backs the queue up until it snaps forward — the observed jerk.

The `run` argument never carried the one fact that matters (the step interval). RunUO passed `true` in combat / `false` for pets and gated it on `dist > 5`; #2271 flipped every combat site to `false`; pets passed `currentDistance > 2`. None of that is a coherent signal.

### What

**Pace-derived run flag**
- `BaseAI.ShouldRun()`: run iff the effective step delay (move clock + badly-hurt inflation) is shorter than `Movement.WalkFootDelay` / `WalkMountDelay` (mounted or flying) — with a continuity rule: an *isolated* step (taken after standing at least a walk interval) goes out as a walk, because the client renders each step alone and a lone run-flagged step is a 200 ms dart. Only a continuing cadence flags run; a true sprinter (pace under the run interpolation) always runs, since a walk-rendered first step would flood the client's 5-step queue. This reproduces RunUO's close-in feel (its `dist > 5` gate) from first principles.
- `DoMoveImpl` stamps the bit; it is the single place the flag is set.
- `run` removed from `MoveTo`, `WalkMobileRange`, `ApproachTarget`, `MoveToPoint`, `MoveToWithGroup`, `MoveToWithCollisionAvoidance`, the move intent, and `PathFollower.Follow`. All 35 call sites updated. **API change** for custom scripts — documented in the RunUO migration docs (`09-items-mobiles-creatures.md`, `11-api-reference.md`) and `content-patterns.md` § Creature Speeds.

**Move-budget pacing fixes** (each confirmed by UTC-aligned server/client step traces)
- A stall no longer banks catch-up steps: the budget's snap-to-now released up to three steps in ~300 ms when a creature resumed chasing after standing beside its target — rendered as a teleport.
- Debt accrual removed entirely: a step landing sub-period late (think-grid vs budget misalignment during reactive mirroring) kept the remainder and fired a follow-up ~100 ms later — a dart pair. `ConsumeMoveBudget` now paces every step from when it was actually taken; in continuous pursuit the move-wake lands within wheel resolution of the deadline, so the cost is single-digit-ms drift.
- Net effect: a creature can never step faster than its pace, verified across a full chase session (zero sub-pace steps; metronomic 350 ms cadence for a 0.3 s lich).

- Test fixture now runs `Movement.Configure()` (the walk delays were 0 in tests).

### Accepted trade-off

Animal (LOW group) bodies without a run animation slide on their stand frames when flagged as running. Most are slow enough to stay flagged as walking; the client-side fallback is in ClassicUO/ClassicUO#1930.

### Tests

`RunFlagTests`: foot thresholds (0.3 / 0.125 run; 0.4 / 0.45 / 1.05 walk), flying uses the mount threshold, badly-hurt inflation flips a 0.35 s creature back to walk, a real `DoMove` stamps the bit, isolated steps drop to walk (sprinters keep running), a stall restarts the cadence with no banked steps, and a late step earns no quicker follow-up. Full suite: 837 Server + 747 UOContent green.
2026-08-30 16:48:52 -07:00

251 lines
6.8 KiB
C#

using System;
using System.Collections.Generic;
using ModernUO.Serialization;
using Server.Items;
using Server.Mobiles;
using Server.Spells;
using Server.Spells.Necromancy;
using Server.Spells.Ninjitsu;
namespace Server.Spells.Ninjitsu
{
public class MirrorImage : NinjaSpell
{
private static readonly Dictionary<Mobile, int> _cloneCount = new();
private static readonly SpellInfo _info = new(
"Mirror Image",
null,
-1,
9002
);
public MirrorImage(Mobile caster, Item scroll) : base(caster, scroll, _info)
{
}
public override TimeSpan CastDelayBase => TimeSpan.FromSeconds(1.5);
public override double RequiredSkill => Core.ML ? 20.0 : 40.0;
public override int RequiredMana => 10;
public override bool BlockedByAnimalForm => false;
public static bool HasClone(Mobile m) => _cloneCount.ContainsKey(m);
public static void AddClone(Mobile m)
{
if (m != null)
{
_cloneCount[m] = 1 + _cloneCount.GetValueOrDefault(m, 0);
}
}
public static void RemoveClone(Mobile m)
{
_cloneCount.Remove(m, out var count);
if (m == null || count <= 0)
{
return;
}
_cloneCount[m] = count - 1;
}
public override bool CheckCast()
{
if (Caster.Mounted)
{
Caster.SendLocalizedMessage(1063132); // You cannot use this ability while mounted.
return false;
}
if (Caster.Followers + 1 > Caster.FollowersMax)
{
// You cannot summon a mirror image because you have too many followers.
Caster.SendLocalizedMessage(1063133);
return false;
}
if (TransformationSpellHelper.UnderTransformation(Caster, typeof(HorrificBeastSpell)))
{
Caster.SendLocalizedMessage(1061091); // You cannot cast that spell in this form.
return false;
}
return base.CheckCast();
}
public override bool CheckDisturb(DisturbType type, bool firstCircle, bool resistable) => false;
public override void OnBeginCast()
{
base.OnBeginCast();
Caster.SendLocalizedMessage(1063134); // You begin to summon a mirror image of yourself.
}
public override void OnCast()
{
if (Caster.Mounted)
{
Caster.SendLocalizedMessage(1063132); // You cannot use this ability while mounted.
}
else if (Caster.Followers + 1 > Caster.FollowersMax)
{
// You cannot summon a mirror image because you have too many followers.
Caster.SendLocalizedMessage(1063133);
}
else if (TransformationSpellHelper.UnderTransformation(Caster, typeof(HorrificBeastSpell)))
{
Caster.SendLocalizedMessage(1061091); // You cannot cast that spell in this form.
}
else if (CheckSequence())
{
Caster.FixedParticles(0x376A, 1, 14, 0x13B5, EffectLayer.Waist);
Caster.PlaySound(0x511);
new Clone(Caster).MoveToWorld(Caster.Location, Caster.Map);
}
FinishSequence();
}
}
}
namespace Server.Mobiles
{
[SerializationGenerator(0)]
public partial class Clone : BaseCreature
{
[SerializableField(0)]
private Mobile _caster;
public Clone(Mobile caster) : base(AIType.AI_Melee, FightMode.None)
{
_caster = caster;
Body = caster.Body;
Hue = caster.Hue;
Female = caster.Female;
Name = caster.Name;
NameHue = caster.NameHue;
Title = caster.Title;
Kills = caster.Kills;
HairItemID = caster.HairItemID;
HairHue = caster.HairHue;
FacialHairItemID = caster.FacialHairItemID;
FacialHairHue = caster.FacialHairHue;
for (var i = 0; i < caster.Skills.Length; ++i)
{
var skill = Skills[i];
var casterSkill = caster.Skills[i];
skill.Base = casterSkill.Base;
skill.Cap = casterSkill.Cap;
}
for (var i = 0; i < caster.Items.Count; i++)
{
AddItem(CloneItem(caster.Items[i]));
}
Warmode = true;
Summoned = true;
SummonMaster = caster;
ControlOrder = OrderType.Follow;
ControlTarget = caster;
AddClone();
}
private void AddClone()
{
var duration = TimeSpan.FromSeconds(30.0 + _caster.Skills.Ninjitsu.Value / 4.0);
new UnsummonTimer(this, duration).Start();
SummonEnd = Core.Now + duration;
MirrorImage.AddClone(_caster);
}
protected override BaseAI ForcedAI => new CloneAI(this);
public override bool DeleteCorpseOnDeath => true;
public override bool IsDispellable => false;
public override bool Commandable => false;
public override bool IsHumanInTown() => false;
private static Item CloneItem(Item item)
{
var newItem = new Item(item.ItemID);
newItem.Hue = item.Hue;
newItem.Layer = item.Layer;
return newItem;
}
public override void OnDamage(int amount, Mobile from, bool willKill)
{
Delete();
}
public override void OnDelete()
{
Effects.SendLocationParticles(
EffectItem.Create(Location, Map, EffectItem.DefaultDuration),
0x3728,
10,
15,
5042
);
base.OnDelete();
}
public override void OnAfterDelete()
{
MirrorImage.RemoveClone(_caster);
base.OnAfterDelete();
}
[AfterDeserialization]
private void AfterDeserialization()
{
AddClone();
}
}
public class CloneAI : BaseAI
{
public CloneAI(Clone m) : base(m) => m.SetCurrentSpeedToActive();
public override bool CanDetectHidden => false;
public override bool Think()
{
// Clones only follow their owners
var master = Mobile.SummonMaster;
if (master?.Map == Mobile.Map && master?.InRange(Mobile, Mobile.RangePerception) == true)
{
WalkMobileRange(master, 2, 0, 1);
}
else
{
WalkRandom(2, 2, 1);
}
return true;
}
}
}