Invoke on collision enter + start of attach child colliders to rigidbody

+ Changed default Namespace of ScriptCore to GlitchyEngine
+ Implicit Casts float2 <-> b2Vec2
+ Entity constructor internal
+ Renamed RigidBody2D to Rigidbody2D (notice the B)
+ Basic Debug Draw actual 2D Colliders
+ Added Entity::GetParentWithComponent

GlitchyEditor/src/EditorLayer.bf

@@ -405,7 +405,7 @@ namespace GlitchyEditor
 			
 			for (var (entity, transform, collider) in _activeScene.GetEntities<TransformComponent, BoxCollider2DComponent>())
 			{
-				Renderer2D.DrawRect(transform.WorldTransform * Matrix.Translation(collider.Offset.X, collider.Offset.Y, 0) * Matrix.Scaling(collider.Size.X * 2, collider.Size.Y * 2, 0));
+				Renderer2D.DrawRect(transform.WorldTransform * Matrix.Translation(collider.Offset.X, collider.Offset.Y, 0) * Matrix.Scaling(collider.Size.X * 2, collider.Size.Y * 2, 0), .Green);
 			}
 
 			for (var (entity, transform, collider) in _activeScene.GetEntities<TransformComponent, CircleCollider2DComponent>())

GlitchyEngine/src/Math/floatVector.bf

@@ -24,6 +24,14 @@ public struct float2
 	{
 		return half2((half)value.X, (half)value.Y);
 	}
+	
+	[Inline]
+#unwarn
+	public static implicit operator Box2D.b2Vec2(in Self value) => *(Box2D.b2Vec2*)&value;
+
+	[Inline]
+#unwarn
+	public static implicit operator Self(in Box2D.b2Vec2 value) => *(Self*)&value;
 }
 
 [BonTarget]

GlitchyEngine/src/Scripting/Classes/Collision2D.bf

@@ -0,0 +1,14 @@
+using System;
+using GlitchyEngine.Core;
+
+namespace GlitchyEngine.Scripting.Classes;
+
+[Ordered, Packed]
+struct Collision2D
+{
+	public UUID Entity;
+	public UUID OtherEntity;
+
+	public UUID Rigidbody;
+	public UUID OtherRigidbody;
+}

GlitchyEngine/src/Scripting/ScriptClass.bf

@@ -2,6 +2,7 @@ using Mono;
 using System;
 using GlitchyEngine.Core;
 using System.Collections;
+using GlitchyEngine.Scripting.Classes;
 
 namespace GlitchyEngine.Scripting;
 
@@ -287,6 +288,14 @@ class ScriptClass : SharpClass
 	private OnCreateMethod _onCreate;
 	private OnUpdateMethod _onUpdate;
 	private OnDestroyMethod _onDestroy;
+	
+	private function [CallingConvention(.Cdecl)] MonoObject*(MonoObject* instance, Collision2D collision, MonoException** exception) _onCollisionEnter2D;
+
+	//private OnCollisionEnter2DMethod _onCollisionEnter2D;
+	private OnDestroyMethod _onCollisionLeave2D;
+	private MonoMethod* _onCollisionEnter2DMethod;
+
+	public bool HasCollisionEnter2D => _onCollisionEnter2D != null;
 
 	/*public StringView Namespace => _namespace;
 	public StringView ClassName => _className;
@@ -303,6 +312,11 @@ class ScriptClass : SharpClass
 		_onCreate = (OnCreateMethod)GetMethodThunk("OnCreate");
 		_onUpdate = (OnUpdateMethod)GetMethodThunk("OnUpdate", 1);
 		_onDestroy = (OnDestroyMethod)GetMethodThunk("OnDestroy");
+
+		_onCollisionEnter2D = (.)GetMethodThunk("OnCollisionEnter2D", 1);
+		_onCollisionLeave2D = (OnDestroyMethod)GetMethodThunk("OnCollisionLeave2D");
+
+		_onCollisionEnter2DMethod = GetMethod("OnCollisionEnter2D", 1);
 	}
 
 	public void OnCreate(MonoObject* instance, out MonoException* exception)
@@ -328,6 +342,22 @@ class ScriptClass : SharpClass
 		if (_onDestroy != null)
 			_onDestroy(instance, &exception);
 	}
+	
+	public void OnCollisionEnter2D(MonoObject* instance, Collision2D collision, out MonoException* exception)
+	{
+		exception = null;
+
+		// TODO: use method thunk
+		if (_onCollisionEnter2DMethod != null)
+		{
+#unwarn
+			void*[1] args = .(&collision);
+
+			Invoke(_onCollisionEnter2DMethod, instance, (.)&args);
+		}
+		// if (_onCollisionEnter2D != null)
+		//	_onCollisionEnter2D(instance, collision, &exception);
+	}
 
 	public MonoObject* CreateInstance(UUID uuid, out MonoException* exception)
 	{

GlitchyEngine/src/Scripting/ScriptGlue.bf

@@ -64,7 +64,7 @@ static class ScriptGlue
 		s_RemoveComponentMethods.Clear();
 
 		RegisterComponent<TransformComponent>("GlitchyEngine.Transform");
-		RegisterComponent<Rigidbody2DComponent>("GlitchyEngine.RigidBody2D");
+		RegisterComponent<Rigidbody2DComponent>("GlitchyEngine.Rigidbody2D");
 	}
 
 	[RegisterMethod]
@@ -99,7 +99,7 @@ static class ScriptGlue
 		}
 		else
 		{
-			Log.EngineLogger.AssertDebug(managedType != null, scope $"No C# component with name \"{{className}}\" found for Beef type \"{typeof(T)}\"");
+			Log.EngineLogger.AssertDebug(managedType != null, scope $"No C# component with name \"{className}\" found for Beef type \"{typeof(T)}\"");
 		}
 	}
 

GlitchyEngine/src/Scripting/ScriptInstance.bf

@@ -1,6 +1,7 @@
 using Mono;
 using GlitchyEngine.Core;
 using System;
+using GlitchyEngine.Scripting.Classes;
 
 namespace GlitchyEngine.Scripting;
 
@@ -80,6 +81,17 @@ class ScriptInstance : RefCounter
 		if (exception != null)
 			ScriptEngine.HandleMonoException(exception, this);
 	}
+	
+	public void InvokeOnCollisionEnter2D(Collision2D collision)
+	{
+		if (!_scriptClass.HasCollisionEnter2D)
+			return;
+
+		_scriptClass.OnCollisionEnter2D(_instance, collision, let exception);
+		
+		if (exception != null)
+			ScriptEngine.HandleMonoException(exception, this);
+	}
 
 	public T GetFieldValue<T>(ScriptField field)
 	{

GlitchyEngine/src/World/Entity.bf

@@ -91,7 +91,24 @@ namespace GlitchyEngine.World
 
 			return _scene._ecsWorld.GetComponent<T>(_entity);
 		}
-		
+
+		/// Returns this entity or the closest parent that has the given component.
+		public (Entity parent, T* component) GetParentWithComponent<T>() where T: struct, new
+		{
+			Entity? walker = this;
+
+			while (walker?.IsValid == true)
+			{
+				T* component = null;
+				if (walker?.TryGetComponent<T>(out component) == true)
+					return (walker.Value, component);
+
+				walker = walker?.Parent;
+			}
+
+			return (.(), null);
+		}
+
 		public bool HasComponent<T>() where T: struct, new
 		{
 			return _scene._ecsWorld.HasComponent<T>(_entity);

GlitchyEngine/src/World/Scene.bf

@@ -6,6 +6,8 @@ using Box2D;
 using GlitchyEngine.Core;
 using GlitchyEngine.Content;
 using GlitchyEngine.Scripting;
+using GlitchyEngine.Math;
+using GlitchyEngine.Scripting.Classes;
 
 namespace GlitchyEngine.World
 {
@@ -17,6 +19,8 @@ namespace GlitchyEngine.World
 		internal EcsWorld _ecsWorld = new .() ~ delete _;
 
 		internal b2World* _physicsWorld2D;
+		b2ContactListener _contactListener;
+		b2Draw draw = .();
 
 		private Dictionary<Type, function void(Entity entity, Type componentType, void* component)> _onComponentAddedHandlers = new .() ~ delete _;
 
@@ -173,14 +177,143 @@ namespace GlitchyEngine.World
 		
 		public void OnSimulationStart()
 		{
-			_physicsWorld2D = Box2D.World.Create(ref _gravity2D);
+			_physicsWorld2D = World.Create(ref _gravity2D);
+			
+			_contactListener = b2ContactListener();
+			_contactListener.beginContactCallback = (contact, userData) =>
+				{
+					// TODO: This is bare minimum! Later we need to take hierarchies into account.
+					// e.g. A is parent of B and B gets event -> A needs to get event too!
 
+					var fixtureA = Contact.GetFixtureA(contact);
+					var fixtureB = Contact.GetFixtureB(contact);
+
+					var bodyA = Fixture.GetBody(fixtureA);
+					var bodyB = Fixture.GetBody(fixtureB);
+
+					// Cast is obviously 64bit only
+					var colliderEntityHandleA = (EcsEntity)(uint)Fixture.GetUserData(fixtureA);
+					var colliderEntityHandleB = (EcsEntity)(uint)Fixture.GetUserData(fixtureB);
+
+					Entity colliderEntityA = .(colliderEntityHandleA, ScriptEngine.Context);
+					Entity colliderEntityB = .(colliderEntityHandleB, ScriptEngine.Context);
+
+					// Cast is obviously 64bit only
+					var rigidbodyEntityHandleA = (EcsEntity)(uint)Body.GetUserData(bodyA);
+					var rigidbodyEntityHandleB = (EcsEntity)(uint)Body.GetUserData(bodyB);
+
+					Entity rigidbodyEntityA = .(rigidbodyEntityHandleA, ScriptEngine.Context);
+					Entity rigidbodyEntityB = .(rigidbodyEntityHandleB, ScriptEngine.Context);
+
+					bool fireEventA = colliderEntityA.TryGetComponent<ScriptComponent>(let scriptOfColliderA);
+					fireEventA |= rigidbodyEntityA.TryGetComponent<ScriptComponent>(let scriptOfRigidbodyA);
+
+					if (fireEventA)
+					{
+						Collision2D collision = .();
+						collision.Entity = colliderEntityA.UUID;
+						collision.OtherEntity = colliderEntityB.UUID;
+						collision.Rigidbody = rigidbodyEntityA.UUID;
+						collision.OtherRigidbody = rigidbodyEntityB.UUID;
+						
+						scriptOfColliderA?.Instance?.InvokeOnCollisionEnter2D(collision);
+						scriptOfRigidbodyA?.Instance?.InvokeOnCollisionEnter2D(collision);
+					}
+
+					bool fireEventB = colliderEntityB.TryGetComponent<ScriptComponent>(let scriptOfColliderB);
+					fireEventB |= rigidbodyEntityB.TryGetComponent<ScriptComponent>(let scriptOfRigidbodyB);
+					
+					if (fireEventB)
+					{
+						Collision2D collision = .();
+						collision.Entity = colliderEntityB.UUID;
+						collision.OtherEntity = colliderEntityA.UUID;
+						collision.Rigidbody = rigidbodyEntityB.UUID;
+						collision.OtherRigidbody = rigidbodyEntityA.UUID;
+						
+						scriptOfColliderB?.Instance?.InvokeOnCollisionEnter2D(collision);
+						scriptOfRigidbodyB?.Instance?.InvokeOnCollisionEnter2D(collision);
+					}
+				};
+
+			World.SetContactListener(_physicsWorld2D, &_contactListener);
+
+			draw.drawPolygonCallback = (vertices, vertexCount, color, userData) =>
+				{
+					for (int i = 1; i < vertexCount; i++)
+					{
+						let start = vertices[i - 1];
+						let end = vertices[i];
+
+						Renderer2D.DrawLine(float3(start.x, start.y, 0.0f), float3(end.x, end.y, 0.0f), *(ColorRGBA*)&color);
+					}
+					let start = vertices[vertexCount - 1];
+					let end = vertices[0];
+
+					Renderer2D.DrawLine(float3(start.x, start.y, 0.0f), float3(end.x, end.y, 0.0f), *(ColorRGBA*)&color);
+				};
+			draw.drawSolidPolygonCallback = (vertices, vertexCount, color, userData) =>
+				{
+					for (int i = 1; i < vertexCount; i++)
+					{
+						let start = vertices[i - 1];
+						let end = vertices[i];
+
+						Renderer2D.DrawLine(float3(start.x, start.y, 0.0f), float3(end.x, end.y, 0.0f), *(ColorRGBA*)&color);
+					}
+					let start = vertices[vertexCount - 1];
+					let end = vertices[0];
+
+					Renderer2D.DrawLine(float3(start.x, start.y, 0.0f), float3(end.x, end.y, 0.0f), *(ColorRGBA*)&color);
+				};
+			draw.drawCircleCallback = (center, radius, color, userData) =>
+				{
+					Renderer2D.DrawCircle(center, radius.XX, *(ColorRGBA*)&color, 0.1f);
+				};
+			draw.drawSolidCircleCallback = (center, radius, axis, color, userData) =>
+				{
+					Renderer2D.DrawCircle(center, radius.XX, *(ColorRGBA*)&color);
+				};
+			draw.drawSegmentCallback = (p1, p2, color, userData) =>
+				{
+				};
+			draw.drawPointCallback = (p, size, color, userData) =>
+				{
+				};
+			draw.drawTransformCallback = (xf, userData) =>
+				{
+				};
+			draw.userData = Internal.UnsafeCastToPtr(_physicsWorld2D);
+
+			World.SetDebugDraw(_physicsWorld2D, &draw);
+			World.SetDebugDrawFlags(_physicsWorld2D, .e_shapeBit);
+
+			InitPhysics2D();
+		}
+
+		private void InitPhysics2D()
+		{
+			// Initialize all Rigidbodies
 			for (let (ecsHandle, rigidBody) in _ecsWorld.Enumerate<Rigidbody2DComponent>())
 			{
 				Entity entity = .(ecsHandle, this);
 
 				InitializeRigidbody2D(entity, rigidBody);
 			}
+
+			for (let (ecsHandle, boxCollider) in _ecsWorld.Enumerate<BoxCollider2DComponent>())
+			{
+				Entity entity = .(ecsHandle, this);
+
+				InitBoxCollider2D(entity, boxCollider);
+			}
+
+			for (let (ecsHandle, circleCollider) in _ecsWorld.Enumerate<CircleCollider2DComponent>())
+			{
+				Entity entity = .(ecsHandle, this);
+
+				InitCircleCollider2D(entity, circleCollider);
+			}
 		}
 
 		private void InitializeRigidbody2D(Entity entity, Rigidbody2DComponent* rigidBody)
@@ -189,49 +322,117 @@ namespace GlitchyEngine.World
 
 			b2BodyDef def = .();
 			def.type = GetBox2DBodyType(rigidBody.BodyType);
+			def.userData = (void*)(uint)entity.Handle;
 
-			// TODO: breaks with hierarchy
+			// TODO: check how stable this is
-			def.position = b2Vec2(transform.Position.X, transform.Position.Y);
+			Matrix.Decompose(transform.WorldTransform, let worldPosition, let worldRotation, let worldScale);
-			def.angle = transform.RotationEuler.Z;
+			float3 worldRotationEuler = Quaternion.ToEulerAngles(worldRotation);
+
+			def.position = b2Vec2(worldPosition.X, worldPosition.Y);
+			def.angle = worldRotationEuler.Z;
 
 			b2Body* body = Box2D.World.CreateBody(_physicsWorld2D, &def);
 			Box2D.Body.SetFixedRotation(body, rigidBody.FixedRotation);
 
 			rigidBody.RuntimeBody = body;
+		}
 
-			if (entity.TryGetComponent<BoxCollider2DComponent>(let boxCollider))
+		private Result<void> FindParentWithRigidbody(Entity entity, out Entity walker, out Rigidbody2DComponent* rigidbody, out Matrix rigidbodyTransform)
+		{
+			walker = entity;
+			rigidbody = null;
+			rigidbodyTransform = .Identity;
+
+			while (true)
 			{
-				b2Shape* boxShape = Box2D.Shape.CreatePolygon();
+				// Found the parent with our beloved component
-				Box2D.Shape.PolygonSetAsBox(boxShape, boxCollider.Size.X * transform.Scale.X, boxCollider.Size.Y * transform.Scale.Y);
+				if (walker.TryGetComponent<Rigidbody2DComponent>(out rigidbody) == true)
-				Box2D.Shape.PolygonSetAsBoxWithCenterAngle(boxShape, boxCollider.Size.X * transform.Scale.X, boxCollider.Size.Y * transform.Scale.Y, ref boxCollider.b2Offset, 0.0f);
+					break;
 
-				b2FixtureDef fixtureDef = .();
+				let parent = walker.Parent;
-				fixtureDef.shape = boxShape;
-				fixtureDef.density = boxCollider.Density;
-				fixtureDef.friction = boxCollider.Friction;
-				fixtureDef.restitution = boxCollider.Restitution;
-				fixtureDef.restitutionThreshold = boxCollider.RestitutionThreshold;
 
-				b2Fixture* fixture = Box2D.Body.CreateFixture(body, &fixtureDef);
+				// We need a rigid body
-				boxCollider.RuntimeFixture = fixture;
+				if (parent == null)
+				{
+					Log.ClientLogger.Warning($"Entity {entity.Name} ({entity.Handle}) has a collider but no parent with a rigid body!");
+					return .Err;
+				}
+				
+				// Construct transform matrix from our local space to the rigidbody space
+				rigidbodyTransform = rigidbodyTransform * walker.Transform.LocalTransform;
+
+				walker = parent.Value;
 			}
 
-			if (entity.TryGetComponent<CircleCollider2DComponent>(let circleCollider))
+			return .Ok;
+		}
+
+		private void InitBoxCollider2D(Entity entity, BoxCollider2DComponent* boxCollider)
+		{
+			if (FindParentWithRigidbody(entity, let entityWithRigidbody, let rigidbody, let parentToRigidbody) case .Err)
+				return;
+
+			let localToWorld = entity.Transform.WorldTransform;
+			let worldToRigidbody = entityWithRigidbody.Transform.WorldTransform.Invert();
+
+			let boxShape = Box2D.Shape.CreatePolygon();
+
+			Box2D.b2Vec2[4] points = .(
+				.(-1, -1),
+				.( 1, -1),
+				.( 1,  1),
+				.(-1,  1));
+
+			for (int i < 4)
 			{
-				b2Shape* circleShape = Box2D.Shape.CreateCircle();
+				points[i] = ((float2)points[i] * boxCollider.Size + boxCollider.Offset);
-				Box2D.Shape.CircleSetPosition(circleShape, ref circleCollider.b2Offset);
-				Box2D.Shape.SetRadius(circleShape, circleCollider.Radius);
 
-				b2FixtureDef fixtureDef = .();
+				if (entity == entityWithRigidbody)
-				fixtureDef.shape = circleShape;
+					 points[i] = entity.Transform.Scale.XY * (float2)points[i];
-				fixtureDef.density = circleCollider.Density;
-				fixtureDef.friction = circleCollider.Friction;
-				fixtureDef.restitution = circleCollider.Restitution;
-				fixtureDef.restitutionThreshold = circleCollider.RestitutionThreshold;
 
-				b2Fixture* fixture = Box2D.Body.CreateFixture(body, &fixtureDef);
+				points[i] = (worldToRigidbody * localToWorld * float4(points[i], 0, 1)).XY;
-				circleCollider.RuntimeFixture = fixture;
 			}
+
+			Shape.PolygonSet(boxShape, &points, 4);
+
+			b2FixtureDef fixtureDef = .();
+			fixtureDef.shape = boxShape;
+			fixtureDef.density = boxCollider.Density;
+			fixtureDef.friction = boxCollider.Friction;
+			fixtureDef.restitution = boxCollider.Restitution;
+			fixtureDef.restitutionThreshold = boxCollider.RestitutionThreshold;
+			fixtureDef.userData = (void*)(uint)entity.Handle;
+
+			Log.EngineLogger.AssertDebug(rigidbody.RuntimeBody != null);
+			b2Fixture* fixture = Box2D.Body.CreateFixture(rigidbody.RuntimeBody, &fixtureDef);
+			boxCollider.RuntimeFixture = fixture;
+		}
+
+		private void InitCircleCollider2D(Entity entity, CircleCollider2DComponent* circleCollider)
+		{
+			if (FindParentWithRigidbody(entity, let entityWithRigidbody, let rigidbody, let parentToRigidbody) case .Err)
+				return;
+
+			let localToWorld = entity.Transform.WorldTransform;
+			let worldToRigidbody = entityWithRigidbody.Transform.WorldTransform.Invert();
+
+			b2Vec2 center = (worldToRigidbody * localToWorld * float4(circleCollider.b2Offset, 0, 1)).XY;
+
+			b2Shape* circleShape = Box2D.Shape.CreateCircle();
+			Box2D.Shape.CircleSetPosition(circleShape, center);
+			Box2D.Shape.SetRadius(circleShape, circleCollider.Radius);
+
+			b2FixtureDef fixtureDef = .();
+			fixtureDef.shape = circleShape;
+			fixtureDef.density = circleCollider.Density;
+			fixtureDef.friction = circleCollider.Friction;
+			fixtureDef.restitution = circleCollider.Restitution;
+			fixtureDef.restitutionThreshold = circleCollider.RestitutionThreshold;
+			fixtureDef.userData = (void*)(uint)entity.Handle;
+
+			Log.EngineLogger.AssertDebug(rigidbody.RuntimeBody != null);
+			b2Fixture* fixture = Box2D.Body.CreateFixture(rigidbody.RuntimeBody, &fixtureDef);
+			circleCollider.RuntimeFixture = fixture;
 		}
 
 		public void OnSimulationStop()
@@ -335,8 +536,24 @@ namespace GlitchyEngine.World
 						b2Vec2 position = Box2D.Body.GetPosition(body);
 						float angle = Box2D.Body.GetAngle(body);
 
-						transform.Position = .(position.x, position.y, transform.Position.Z);
+						if (entity.Parent != null)
-						transform.RotationEuler = .(transform.RotationEuler.XY, angle);
+						{
+							Matrix worldToParent = entity.Parent.Value.Transform.WorldTransform.Invert();
+
+							float4 newLocalPosition = worldToParent * float4(position, 0, 1);
+							transform.Position = float3(newLocalPosition.XY, transform.Position.Z);
+
+							// TODO: when the parent of the rigidbody-entity is rotated, the rotation is applied wrong...
+							Matrix.Decompose(worldToParent, let p, var worldToParentRotation, let s);
+							Quaternion newLocalRotation = (worldToParentRotation * Quaternion.FromEulerAngles(0, 0, angle))..Normalize();
+							// TODO: when the parent has rotation on X or Y everything breaks even more...
+							transform.Rotation = (newLocalRotation * Quaternion.FromEulerAngles(transform.RotationEuler.Y, transform.RotationEuler.X, 0))..Normalize();
+						}
+						else
+						{
+							transform.Position = .(position.x, position.y, transform.Position.Z);
+							transform.RotationEuler = .(transform.RotationEuler.XY, angle);
+						}
 					}
 				}
 			}

GlitchyEngine/src/World/SceneRenderer.bf

@@ -192,6 +192,9 @@ class SceneRenderer
 
 		DrawDebug2D();
 
+		if (Scene._physicsWorld2D != null)
+			Box2D.World.DebugDraw(Scene._physicsWorld2D);
+
 		Renderer2D.EndScene();
 
 		// Gamma correct composit target and draw it into viewport

ScriptCore/Components/RigidBody2D.cs

@@ -2,7 +2,7 @@ using GlitchyEngine.Math;
 
 namespace GlitchyEngine;
 
-public class RigidBody2D : Component
+public class Rigidbody2D : Component
 {
     /// <summary>
     /// Apply a force at a world point.

ScriptCore/Entity.cs

@@ -15,17 +15,13 @@ internal struct EntityHandle
 
 public class Entity : EngineObject
 {
-    //private UUID _uuid;
-
-    //public UUID UUID => _uuid;
-
     /// <summary>
     /// Empty constructor not used. Do NOT USE!
     /// </summary>
     protected Entity()
     { }
 
-    private Entity(UUID uuid)
+    internal Entity(UUID uuid)
     {
         _uuid = uuid;
     }

ScriptCore/Physics/Collision2D.cs

@@ -0,0 +1,35 @@
+using System.Runtime.InteropServices;
+using GlitchyEngine.Core;
+
+namespace GlitchyEngine.Physics;
+
+[StructLayout(LayoutKind.Sequential, Pack=1)]
+public struct Collision2D
+{
+    private UUID _entity;
+    private UUID _otherEntity;
+
+    private UUID _rigidbody;
+    private UUID _otherRigidbody;
+
+    /// <summary>
+    /// Gets the Entity whose Collider takes part in the collision.
+    /// This entity is either the entity of the script instance receiving the event or a child of it.
+    /// </summary>
+    public Entity Entity => new(_entity);
+    /// <summary>
+    /// Gets the other Entity whose collider takes part in the collision.
+    /// </summary>
+    public Entity OtherEntity => new(_otherEntity);
+
+    /// <summary>
+    /// Gets the rigidbody whose Collider takes part in the collision.
+    /// This Rigidbody is either a component of the entity whose script instance received the event or a parent of it.
+    /// </summary>
+    public Rigidbody2D Rigidbody => new() { Entity = Entity };
+
+    /// <summary>
+    /// Gets the other rigidbody whose Collider takes part in the collision.
+    /// </summary>
+    public Rigidbody2D OtherRigidbody => new() { Entity = OtherEntity };
+}

ScriptCore/ScriptCore.csproj

@@ -5,6 +5,7 @@
 	  <LangVersion>latest</LangVersion>
 	  <BaseOutputPath></BaseOutputPath>
 	  <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
+	  <RootNamespace>GlitchyEngine</RootNamespace>
   </PropertyGroup>
 
   <Target Name="PostBuild" AfterTargets="PostBuildEvent">