Add grid merging (#3627)

* Add grid merging * More preliminary cleanup * Fixes * Fixes * weh * tweaks * Tests * weh * Fix direction test * Release notes
2026-09-06 17:58:05 +02:00 · 2024-01-21 17:41:04 +11:00
parent aae929966c
commit 59b3ffda4f
12 changed files with 376 additions and 56 deletions
@@ -0,0 +1,138 @@
+using System.Collections.Generic;
+using System.Numerics;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.Shared.Map.Components;
+using Robust.Shared.Maths;
+using Robust.Shared.Timing;
+using Robust.Shared.Utility;
+
+namespace Robust.Server.Physics;
+
+public sealed partial class GridFixtureSystem
+{
+    /*
+     * Something to keep in mind is that they rotate around the origin of a tile (e.g. 0,0), so a rotation of -90 degrees
+     * moves the origin to 0, -1.
+     */
+
+    /// <summary>
+    /// Merges GridB into GridA.
+    /// </summary>
+    /// <param name="offset">Origin of GridB relative to GridA</param>
+    /// <param name="rotation">Rotation to apply to GridB when being merged.
+    /// Note that the rotation is applied before the offset so the offset itself will be rotated.</param>
+    public void Merge(
+        EntityUid gridAUid,
+        EntityUid gridBUid,
+        Vector2i offset,
+        Angle rotation,
+        MapGridComponent? gridA = null,
+        MapGridComponent? gridB = null,
+        TransformComponent? xformA = null,
+        TransformComponent? xformB = null)
+    {
+        var matrix = Matrix3.CreateTransform(offset, rotation);
+        Merge(gridAUid, gridBUid, matrix, gridA, gridB, xformA, xformB);
+    }
+
+    /// <summary>
+    /// Merges GridB into GridA.
+    /// </summary>
+    /// <param name="offset">Origin of GridB relative to GridA</param>
+    /// <param name="matrix">Matrix to apply to gridB when being merged.
+    /// Note that rotation is applied first and then offset so the offset itself will be rotated.</param>
+    public void Merge(
+        EntityUid gridAUid,
+        EntityUid gridBUid,
+        Matrix3 matrix,
+        MapGridComponent? gridA = null,
+        MapGridComponent? gridB = null,
+        TransformComponent? xformA = null,
+        TransformComponent? xformB = null)
+    {
+        if (!Resolve(gridAUid, ref gridA, ref xformA))
+            return;
+
+        if (!Resolve(gridBUid, ref gridB, ref xformB))
+            return;
+
+        var sw = new Stopwatch();
+        var tiles = new List<(Vector2i Indices, Tile Tile)>();
+        var enumerator = _maps.GetAllTilesEnumerator(gridBUid, gridB);
+
+        while (enumerator.MoveNext(out var tileRef))
+        {
+            var offsetTile = matrix.Transform(new Vector2(tileRef.Value.GridIndices.X, tileRef.Value.GridIndices.Y) + gridA.TileSizeHalfVector);
+            tiles.Add((offsetTile.Floored(), tileRef.Value.Tile));
+        }
+
+        _maps.SetTiles(gridAUid, gridA, tiles);
+
+        enumerator = _maps.GetAllTilesEnumerator(gridBUid, gridB);
+        var rotationDiff = matrix.Rotation();
+
+        while (enumerator.MoveNext(out var tileRef))
+        {
+            var chunkOrigin = SharedMapSystem.GetChunkIndices(tileRef.Value.GridIndices, gridB.ChunkSize);
+
+            if (!_maps.TryGetChunk(gridBUid, gridB, chunkOrigin, out var chunk))
+            {
+                continue;
+            }
+
+            var chunkLocalTile = SharedMapSystem.GetChunkRelative(tileRef.Value.GridIndices, gridB.ChunkSize);
+            var snapgrid = chunk.GetSnapGrid((ushort) chunkLocalTile.X, (ushort) chunkLocalTile.Y);
+
+            if (snapgrid == null || snapgrid.Count == 0)
+                continue;
+
+            var offsetTile = matrix.Transform(new Vector2(tileRef.Value.GridIndices.X, tileRef.Value.GridIndices.Y) + gridA.TileSizeHalfVector);
+            var tileIndex = offsetTile.Floored();
+
+            for (var j = snapgrid.Count - 1; j >= 0; j--)
+            {
+                var ent = snapgrid[j];
+                var xform = _xformQuery.GetComponent(ent);
+                _xformSystem.ReAnchor(ent, xform,
+                    gridB, gridA,
+                    tileRef.Value.GridIndices, tileIndex,
+                    gridBUid, gridAUid,
+                    xformB, xformA,
+                    rotationDiff);
+
+                DebugTools.Assert(xform.ParentUid == gridAUid);
+            }
+
+            DebugTools.Assert(snapgrid.Count == 0);
+        }
+
+        enumerator = _maps.GetAllTilesEnumerator(gridBUid, gridB);
+
+        while (enumerator.MoveNext(out var tileRef))
+        {
+            var bounds = _lookup.GetLocalBounds(tileRef.Value.GridIndices, gridB.TileSize);
+
+            _entSet.Clear();
+            _lookup.GetLocalEntitiesIntersecting(gridBUid, bounds, _entSet, LookupFlags.All | ~LookupFlags.Contained | LookupFlags.Approximate);
+
+            foreach (var ent in _entSet)
+            {
+                // Consider centre of entity position maybe?
+                var entXform = _xformQuery.GetComponent(ent);
+
+                if (entXform.ParentUid != gridBUid ||
+                    !bounds.Contains(entXform.LocalPosition)) continue;
+
+                var newPos = matrix.Transform(entXform.LocalPosition);
+
+                _xformSystem.SetCoordinates(ent, entXform, new EntityCoordinates(gridAUid, newPos), entXform.LocalRotation + rotationDiff, oldParent: xformB, newParent: xformA);
+            }
+        }
+
+        DebugTools.Assert(xformB.ChildCount == 0);
+        Del(gridBUid);
+
+        Log.Debug($"Merged grids in {sw.Elapsed.TotalMilliseconds}ms");
+    }
+}