ModernUO/Projects/UOContent/Engines/Pathing/MovementPath.cs
Kamron Batman 9066e8fd00
feat: expand cache to nearly all mobiles + dynamic-obstacle pass (#2447)
## Summary

Builds on PR #2446's cache-direct A*. The previous PR conservatively routed players + creatures with capability flags entirely through the slow path. This PR pushes that line: most mobile classes now use the cache, with the right rule set layered on top per-mobile, and the cache fast-path now does the dynamic items / mobiles check that PR #2446 had silently skipped.

## What changed

- **Non-GM players** now use the cache. Diagonal corner-cut applies the strict AND-rule (BOTH cardinal partners walkable) by reading the same source-cell mask byte the creature OR-rule reads — both rules are evaluable from one byte.
- **Creatures with `CanOpenDoors` / `CanMoveOverObstacles`** now use the cache. Reading `MovementImpl` confirmed those flags only affect dynamic items, never static tiles, so they were over-conservatively excluded before.
- **Swim creatures** now use the cache via a capability overlay. `StepProbe` bakes a second rule set (`canSwim=true, cantWalk=true`) producing `WetMask` + `SwimZ_*`. The algorithm composes `effectiveMask = (walkMask & !cantWalk) | (wetMask & canSwim)` per direction; walk Z preferred when both apply.
- **Dynamic-obstacle pass.** Cache fast-path now mirrors `MovementImpl`'s per-cell items + mobiles collision check (`GetItemsAt` / `GetMobilesAt` at the target cell, with `CanOpenDoors` / `CanMoveOverObstacles` / spell-field overrides). This closes a correctness gap from PR #2446 — the cache fast-path was silently skipping dynamic obstacles entirely.
- **`StepCache.TryGetMask` returns `StepMask` struct** instead of 11 out parameters. `HitKind` rolls into the struct with an `IsHit` accessor. Sets up wet/swim without ballooning the call site.
- **`StepChunk.MultiZCells` is lazy-init.** Most chunks are entirely single-Z; allocating the 32-byte bitmap up-front wasted ~256KB at full cap.
- **Admin commands.** `[PathCacheStats` (resident chunks + hit/miss/eviction counters) and `[PathCacheClear` (drop everything, zero counters).
- **Feature flag.** `bitmap_pathfinding_cache` (default true) gates the cache fast-path. Flipped off, every cell expansion routes to `MovementImpl` — equivalent to PR #2446's slow-path-only behavior. Safety net for shipping the new behavior.

`RequiresSlowPath` shrinks to just `CanFly` — flying creatures Z-jump arbitrarily, which the cache's static-Z model can't accommodate.
2026-05-06 00:14:08 -07:00

122 lines
3.4 KiB
C#

using System;
using System.Diagnostics;
using Server.Engines.Pathing;
using Server.Engines.Pathing.Cache;
using Server.Items;
using Server.PathAlgorithms;
using Server.PathAlgorithms.BitmapAStar;
using Server.Spells;
using Server.Targeting;
namespace Server
{
public sealed class MovementPath
{
public MovementPath(Mobile m, Point3D goal)
{
var start = m.Location;
var map = m.Map;
Map = map;
Start = start;
Goal = goal;
if (map == null || map == Map.Internal)
{
return;
}
if (Utility.InRange(start, goal, 1))
{
return;
}
try
{
var alg = OverrideAlgorithm ?? BitmapAStarAlgorithm.Instance;
if (alg?.CheckCondition(m, map, start, goal) == true)
{
Directions = alg.Find(m, map, start, goal);
}
}
catch (Exception e)
{
Console.WriteLine("Warning: {0}: Pathing error from {1} to {2}", e.GetType().Name, start, goal);
}
}
public Map Map { get; }
public Point3D Start { get; }
public Point3D Goal { get; }
public Direction[] Directions { get; }
public bool Success => Directions?.Length > 0;
public static PathAlgorithm OverrideAlgorithm { get; set; }
public static void Configure()
{
CommandSystem.Register("Path", AccessLevel.GameMaster, Path_OnCommand);
CacheEvictionTimer.Configure();
PathCacheCommands.Configure();
}
[Usage("Path")]
[Description("Draws a path from your current location to a targeted location.")]
public static void Path_OnCommand(CommandEventArgs e)
{
e.Mobile.BeginTarget(-1, true, TargetFlags.None, Path_OnTarget);
e.Mobile.SendMessage("Target a location and a path will be drawn there.");
}
private static void Path(Mobile from, IPoint3D p, PathAlgorithm alg, string name, int zOffset)
{
OverrideAlgorithm = alg;
var watch = new Stopwatch();
watch.Start();
var path = new MovementPath(from, new Point3D(p));
watch.Stop();
if (!path.Success)
{
from.SendMessage($"{name} path failed: {watch.ElapsedMilliseconds}ms");
}
else
{
from.SendMessage($"{name} path success: {watch.ElapsedMilliseconds}ms");
var x = from.X;
var y = from.Y;
var z = from.Z;
WayPoint waypoint = null;
for (var i = 0; i < path.Directions.Length; ++i)
{
Movement.Movement.Offset(path.Directions[i], ref x, ref y);
waypoint = new WayPoint(waypoint);
waypoint.MoveToWorld(new Point3D(x, y, z + zOffset), from.Map);
}
}
}
public static void Path_OnTarget(Mobile from, object targeted)
{
if (targeted is not IPoint3D p)
{
return;
}
SpellHelper.GetSurfaceTop(ref p);
Path(from, p, BitmapAStarAlgorithm.Instance, "Bitmap", 0);
OverrideAlgorithm = null;
}
}
}