RaycastHit2D.centroid

Description

The world space centroid (center) of the physics query shape when it intersects.

When the RaycastHit2D result is returned from a linecast or raycast query, the centroid is identical to the returned point property because a line or ray uses a very small point with no area, so its position is the same as the position it intersects a Collider2D.

However, when using other physics queries that cast shapes that do have an area such as circles, capsules or boxes, the centroid is the center of the respective shape used when it is in contact with the returned point. For example, a circle will always have its centroid be its radius away from the returned point.

The centroid helps identify the position the shape would be at for it to come into contact at the returned RaycastHit2D.point.

Additional resources: RaycastHit2D.point.

using UnityEngine;

public class Example : MonoBehaviour
{
    // A stationary planet
    public Transform planet;

    // A satellite moving around the planet
    public Transform satellite;

    void Update()
    {
        // Cast a circle with a radius of 10 in from the satellite position to the planet position.
        RaycastHit2D hit = Physics2D.CircleCast(satellite.position, 10.0f, planet.position);

        // If something was hit, draw a line from the planet to the position the satellite would be if it were to hit the planet.
        if (hit)
            Debug.DrawLine(planet.position, hit.centroid, Color.yellow);
    }
}

Additional resources: RaycastHit2D.point.