overlap circle code?

overlap.cs

using UnityEngine;

public class CircleOverlapExample : MonoBehaviour
{
    [System.Serializable]
    public struct Circle
    {
        public Vector2 center;
        public float radius;
    }

    // Returns half the combined overlap perimeter of two circles
    float HalfOverlapPerimeter(Circle c1, Circle c2)
    {
        float dx = c2.center.x - c1.center.x;
        float dy = c2.center.y - c1.center.y;
        float d  = Mathf.Sqrt(dx * dx + dy * dy);
        float r1 = c1.radius, r2 = c2.radius;
        
        // No intersection
        if(d >= r1 + r2) return 0f;

        // One circle completely inside another
        if(d <= Mathf.Abs(r1 - r2))
        {
            float rMin = (r1 < r2) ? r1 : r2;
            return Mathf.PI * 2f * rMin * 0.5f;
        }

        // Partial overlap
        float alpha = 2f * Mathf.Acos((d * d + r1 * r1 - r2 * r2) / (2f * d * r1));
        float beta  = 2f * Mathf.Acos((d * d + r2 * r2 - r1 * r1) / (2f * d * r2));
        float arc1  = r1 * alpha;
        float arc2  = r2 * beta;

        return 0.5f * (arc1 + arc2);
    }

    public Circle c1, c2, c3;

    void Start()
    {
        float halfAB = HalfOverlapPerimeter(c1, c2);
        float halfBC = HalfOverlapPerimeter(c2, c3);
        float halfCA = HalfOverlapPerimeter(c3, c1);

        Debug.Log("AB half-overlap: " + halfAB);
        Debug.Log("BC half-overlap: " + halfBC);
        Debug.Log("CA half-overlap: " + halfCA);
    }
}