v0.10 衝突検出

docs/roadmap.md

@@ -148,10 +148,10 @@
 
 ゴール: オブジェクト同士の衝突を正確に検出できる
 
-- [ ] SpatialHashGrid
-- [ ] BVH広域フェーズ
-- [ ] GJK+EPA狭域フェーズ
-- [ ] Raycast, RaycastAll, SphereCast, OverlapSphere
+- [x] SpatialHashGrid
+- [x] BVH広域フェーズ
+- [x] GJK+EPA狭域フェーズ
+- [x] Raycast, RaycastAll, SphereCast, OverlapSphere
 
 完動品としての価値: オブジェクト同士の衝突が検出される。レイキャストで任意のオブジェクトを特定できる。
 

src/Seed.Engine.Tests/Physics/BroadPhase/BvhTreeTests.cs

@@ -0,0 +1,173 @@
+using System;
+using Xunit;
+
+using Seed.Engine.Ecs;
+using Seed.Engine.Foundation.Collections;
+using Seed.Engine.Foundation.Mathematics;
+using Seed.Engine.Physics.BroadPhase;
+using Seed.Engine.Physics.Collision;
+
+namespace Seed.Engine.Tests.Physics.BroadPhase;
+
+public class BvhTreeTests
+{
+    [Fact]
+    public void Build_SingleElement_CreatesLeafNode()
+    {
+        // Given
+        var bvh = new BvhTree();
+        Span<AABB> bounds = [new AABB(Vector3.Zero, Vector3.One)];
+        Span<int> indices = [0];
+
+        // When
+        bvh.Build(bounds, indices);
+
+        // Then
+        Assert.Equal(1, bvh.NodeCount);
+
+        bvh.Dispose();
+    }
+
+    [Fact]
+    public void Build_MultipleElements_CreatesTree()
+    {
+        // Given
+        var bvh = new BvhTree();
+        Span<AABB> bounds =
+        [
+            new AABB(new Vector3(0f, 0f, 0f), new Vector3(1f, 1f, 1f)),
+            new AABB(new Vector3(5f, 0f, 0f), new Vector3(6f, 1f, 1f)),
+            new AABB(new Vector3(10f, 0f, 0f), new Vector3(11f, 1f, 1f)),
+        ];
+        Span<int> indices = [0, 1, 2];
+
+        // When
+        bvh.Build(bounds, indices);
+
+        // Then: 3 leaves + internal nodes
+        Assert.True(bvh.NodeCount >= 3);
+
+        bvh.Dispose();
+    }
+
+    [Fact]
+    public void QueryAABB_Intersecting_ReturnsMatches()
+    {
+        // Given
+        var bvh = new BvhTree();
+        Span<AABB> bounds =
+        [
+            new AABB(new Vector3(0f, 0f, 0f), new Vector3(1f, 1f, 1f)),
+            new AABB(new Vector3(5f, 0f, 0f), new Vector3(6f, 1f, 1f)),
+            new AABB(new Vector3(10f, 0f, 0f), new Vector3(11f, 1f, 1f)),
+        ];
+        Span<int> indices = [0, 1, 2];
+        bvh.Build(bounds, indices);
+
+        var queryBounds = new AABB(new Vector3(4f, 0f, 0f), new Vector3(7f, 1f, 1f));
+        var results = new NativeList<int>(8);
+
+        // When
+        bvh.QueryAABB(queryBounds, ref results);
+
+        // Then: only index 1 should match
+        Assert.True(results.Length >= 1);
+
+        results.Dispose();
+        bvh.Dispose();
+    }
+
+    [Fact]
+    public void QueryAABB_NonIntersecting_ReturnsEmpty()
+    {
+        // Given
+        var bvh = new BvhTree();
+        Span<AABB> bounds =
+        [
+            new AABB(new Vector3(0f, 0f, 0f), new Vector3(1f, 1f, 1f)),
+        ];
+        Span<int> indices = [0];
+        bvh.Build(bounds, indices);
+
+        var queryBounds = new AABB(new Vector3(50f, 50f, 50f), new Vector3(51f, 51f, 51f));
+        var results = new NativeList<int>(8);
+
+        // When
+        bvh.QueryAABB(queryBounds, ref results);
+
+        // Then
+        Assert.Equal(0, results.Length);
+
+        results.Dispose();
+        bvh.Dispose();
+    }
+
+    [Fact]
+    public void QueryRay_HitsLeaf_ReturnsMatch()
+    {
+        // Given
+        var bvh = new BvhTree();
+        Span<AABB> bounds =
+        [
+            new AABB(new Vector3(4f, -1f, -1f), new Vector3(6f, 1f, 1f)),
+        ];
+        Span<int> indices = [0];
+        bvh.Build(bounds, indices);
+
+        var ray = new Ray(Vector3.Zero, Vector3.UnitX);
+        var results = new NativeList<int>(8);
+
+        // When
+        bvh.QueryRay(ray, 100f, ref results);
+
+        // Then
+        Assert.Equal(1, results.Length);
+        Assert.Equal(0, results[0]);
+
+        results.Dispose();
+        bvh.Dispose();
+    }
+
+    [Fact]
+    public void FindOverlappingPairs_OverlappingLeaves_ReturnsPair()
+    {
+        // Given
+        var bvh = new BvhTree();
+        Span<AABB> bounds =
+        [
+            new AABB(new Vector3(0f, 0f, 0f), new Vector3(2f, 2f, 2f)),
+            new AABB(new Vector3(1f, 0f, 0f), new Vector3(3f, 2f, 2f)),
+        ];
+        Span<int> indices = [0, 1];
+        bvh.Build(bounds, indices);
+
+        Entity e0 = new Entity(0, 1);
+        Entity e1 = new Entity(1, 1);
+        ReadOnlySpan<Entity> entities = [e0, e1];
+        var pairs = new NativeList<CollisionPair>(8);
+
+        // When
+        bvh.FindOverlappingPairs(ref pairs, entities);
+
+        // Then
+        Assert.Equal(1, pairs.Length);
+
+        pairs.Dispose();
+        bvh.Dispose();
+    }
+
+    [Fact]
+    public void Build_Empty_HandlesGracefully()
+    {
+        // Given
+        var bvh = new BvhTree();
+
+        // When
+        bvh.Build(ReadOnlySpan<AABB>.Empty, ReadOnlySpan<int>.Empty);
+
+        // Then
+        Assert.Equal(0, bvh.NodeCount);
+
+        bvh.Dispose();
+    }
+}

src/Seed.Engine.Tests/Physics/BroadPhase/SpatialHashGridTests.cs

@@ -0,0 +1,89 @@
+using Xunit;
+
+using Seed.Engine.Foundation.Collections;
+using Seed.Engine.Foundation.Mathematics;
+using Seed.Engine.Physics.BroadPhase;
+
+namespace Seed.Engine.Tests.Physics.BroadPhase;
+
+public class SpatialHashGridTests
+{
+    [Fact]
+    public void Insert_And_QuerySphere_FindsEntity()
+    {
+        // Given
+        var grid = new SpatialHashGrid(2.0f, 16);
+        var bounds = new AABB(new Vector3(0f, 0f, 0f), new Vector3(1f, 1f, 1f));
+        grid.Insert(0, bounds);
+
+        var results = new NativeList<int>(8);
+
+        // When
+        grid.QuerySphere(new Vector3(0.5f, 0.5f, 0.5f), 1.0f, ref results);
+
+        // Then
+        Assert.True(results.Length >= 1);
+
+        results.Dispose();
+        grid.Dispose();
+    }
+
+    [Fact]
+    public void QuerySphere_FarAway_ReturnsEmpty()
+    {
+        // Given
+        var grid = new SpatialHashGrid(2.0f, 16);
+        var bounds = new AABB(new Vector3(0f, 0f, 0f), new Vector3(1f, 1f, 1f));
+        grid.Insert(0, bounds);
+
+        var results = new NativeList<int>(8);
+
+        // When
+        grid.QuerySphere(new Vector3(100f, 100f, 100f), 1.0f, ref results);
+
+        // Then
+        Assert.Equal(0, results.Length);
+
+        results.Dispose();
+        grid.Dispose();
+    }
+
+    [Fact]
+    public void Clear_RemovesAllEntries()
+    {
+        // Given
+        var grid = new SpatialHashGrid(2.0f, 16);
+        grid.Insert(0, new AABB(Vector3.Zero, Vector3.One));
+
+        // When
+        grid.Clear();
+        var results = new NativeList<int>(8);
+        grid.QuerySphere(new Vector3(0.5f, 0.5f, 0.5f), 1.0f, ref results);
+
+        // Then
+        Assert.Equal(0, results.Length);
+
+        results.Dispose();
+        grid.Dispose();
+    }
+
+    [Fact]
+    public void Insert_MultipleEntities_AllFound()
+    {
+        // Given
+        var grid = new SpatialHashGrid(2.0f, 16);
+        grid.Insert(0, new AABB(new Vector3(0f, 0f, 0f), new Vector3(1f, 1f, 1f)));
+        grid.Insert(1, new AABB(new Vector3(0.5f, 0f, 0f), new Vector3(1.5f, 1f, 1f)));
+
+        var results = new NativeList<int>(8);
+
+        // When
+        grid.QuerySphere(new Vector3(0.5f, 0.5f, 0.5f), 2.0f, ref results);
+
+        // Then
+        Assert.True(results.Length >= 2);
+
+        results.Dispose();
+        grid.Dispose();
+    }
+}