Plane.Raycast

説明

レイを平面と交差させます

This function sets enter to the distance along the ray, where it intersects the plane. If the ray is parallel to the plane, function returns false and sets enter to zero. If the ray is pointing in the opposite direction than the plane, function returns false/ and sets enter to the distance along the ray (negative value).

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    public Plane groundPlane;
    public Transform markerObject;
    void Update() {
        if (Input.GetMouseButtonDown(0)) {
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            float rayDistance;
            if (groundPlane.Raycast(ray, out rayDistance))
                markerObject.position = ray.GetPoint(rayDistance);
            
        }
    }
}

関連項目: Physics.Raycast.