feat: added raycasting support for physics engine 2D

Engine.Physics2D/PhysicsEngine2DStandalone.cs

@@ -19,6 +19,7 @@ public class PhysicsEngine2DStandalone : IPhysicsEngine2D
 
     private readonly ICollisionDetector2D collisionDetector = null!;
     private readonly ICollisionResolver2D collisionResolver = null!;
+    private readonly IRaycastResolver2D raycastResolver = null!;
 
     public int IterationPerStep { get => _iterationCount; set => _iterationCount = value < 1 ? 1 : value; }
 
@@ -43,6 +44,34 @@ public class PhysicsEngine2DStandalone : IPhysicsEngine2D
         rigidBody.BehaviourController.OnBehaviourAdded.RemoveListener(delegateOnBehaviourAdded);
         rigidBody.BehaviourController.OnBehaviourRemoved.RemoveListener(delegateOnBehaviourRemoved);
     }
+    public RaycastResult? Raycast(Ray2D ray, float length = float.MaxValue)
+    {
+        RaycastResult? closestResult = null;
+        float closestDistance = float.MaxValue;
+
+        for (int i = 0; i < colliders.Count; i++)
+            if (raycastResolver.RaycastAgainst(colliders[i], ray, length) is RaycastResult raycastResult)
+            {
+                float magnitudeSquared = raycastResult.Position.FromTo(ray.Origin).MagnitudeSquared;
+
+                if (magnitudeSquared > closestDistance)
+                    continue;
+
+                closestDistance = magnitudeSquared;
+                closestResult = raycastResult;
+            }
+
+        return closestResult;
+    }
+
+    public void Raycast(Ray2D ray, IList<RaycastResult> results, float length = float.MaxValue)
+    {
+        results.Clear();
+
+        for (int i = 0; i < colliders.Count; i++)
+            if (raycastResolver.RaycastAgainst(colliders[i], ray, length) is RaycastResult raycastResult)
+                results.Add(raycastResult);
+    }
 
     public void Step(float deltaTime)
     {
@@ -203,15 +232,17 @@ public class PhysicsEngine2DStandalone : IPhysicsEngine2D
     {
         collisionDetector = new CollisionDetector2D();
         collisionResolver = new CollisionResolver2D();
+        raycastResolver = new RaycastResolver2D();
 
         delegateOnBehaviourAdded = OnBehaviourAdded;
         delegateOnBehaviourRemoved = OnBehaviourRemoved;
     }
 
-    public PhysicsEngine2DStandalone(ICollisionDetector2D collisionDetector, ICollisionResolver2D collisionResolver)
+    public PhysicsEngine2DStandalone(ICollisionDetector2D collisionDetector, ICollisionResolver2D collisionResolver, IRaycastResolver2D raycastResolver)
     {
         this.collisionDetector = collisionDetector;
         this.collisionResolver = collisionResolver;
+        this.raycastResolver = raycastResolver;
 
         delegateOnBehaviourAdded = OnBehaviourAdded;
         delegateOnBehaviourRemoved = OnBehaviourRemoved;