HandleUtility.placeObjectCustomPasses

Description

Subscribe to this event to handle object placement in the SceneView.

This delegate is invoked by PlaceObject when drag and dropping objects from the Hierarchy and Project views.

using UnityEditor;
using UnityEngine;

static class PlaceObjectExample
{
    static readonly Plane s_GroundPlane = new Plane(Vector3.up, Vector3.zero);

    [InitializeOnLoadMethod]
    static void InitPlaceObjectHandler()
    {
        HandleUtility.placeObjectCustomPasses += PlaneRaycast;
    }

    // In this example, we register a plane at the scene origin to test for object placement.
    static bool PlaneRaycast(Vector2 mousePosition, out Vector3 position, out Vector3 normal)
    {
        Ray worldRay = HandleUtility.GUIPointToWorldRay(mousePosition);
        float distance;

        if (s_GroundPlane.Raycast(worldRay, out distance))
        {
            position = worldRay.GetPoint(distance);
            normal = s_GroundPlane.normal;
            return true;
        }

        position = Vector3.zero;
        normal = Vector3.up;
        return false;
    }
}