Camera.WorldToViewportPoint

Description

将 position 从世界空间变换为视口空间。

视口空间是标准化的、相对于摄像机的空间。摄像机左下角为 (0,0)，右上角为 (1,1)。z 位置为与摄像机的距离，采用世界单位。

// Finds out whether target is on the left or right side of the screen
using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour
{
    public Transform target;
    Camera cam;

    void Start()
    {
        cam = GetComponent<Camera>();
    }

    void Update()
    {
        Vector3 viewPos = cam.WorldToViewportPoint(target.position);
        if (viewPos.x > 0.5F)
            print("target is on the right side!");
        else
            print("target is on the left side!");
    }
}