将物体放置在相机前面 [英] Placing an object in front of the camera

问题描述

这应该是一件容易的事，我已经在Google上进行了搜索，但是我不知道为什么这些示例对我有用.

This should be an easy task, and I have googled it, but I can't figure out why any of the examples are working for me.

基本上，我想在第一人称游戏中将瓷砖放置在地面上.我希望将要放置在地面上的物体悬空"在空中，同时为其选择最佳位置.我可以实例化该对象，使其成为播放器相机的子代，但无法将其放置在相机前面X个单位；它总是以在"播放器上结尾；

Basically, I want to place tiles on the ground in my first person game. I want the object I want to place on the ground to "float" in mid-air while choosing the perfect location for it. I can instantiate the object, make it a child of the player camera, but I'm unable to position it X units in front of the camera; it always ends up "on" the player;

public void StartPlacing ( Item item ) {
    Object itemPrefab = Resources.Load( "Prefabs/" + item.prefabName );

    GameObject itemObject = (GameObject)Instantiate( itemPrefab );
    itemObject.transform.parent = playerCamera.transform;

    // What to do here to place it in front of the camera? I've tried this:
    itemObject.localPosition = new Vector3( 0, 0, 5 );
}

更新:摄像机是播放器(角色控制器)的子级，并且摄像机处于透视模式.

UPDATE: The camera is a child of the player (Character Controller), and the camera is in perspective mode.

推荐答案

谢谢大家的有用建议！我想出了适合我需要的以下代码:

Thanks for all the useful suggestions, everyone! I came up with the following code which suits my needs:

using UnityEngine;
using System.Collections;

public class ConstructionController : MonoBehaviour {

    private Camera playerCamera;
    private GameObject itemObject;
    private float distance = 3.0f;

    // Use this for initialization
    void Start () {
        playerCamera = GetComponentInChildren<Camera>();
    }

    // Update is called once per frame
    void Update () {

        if ( itemObject != null ) {
            itemObject.transform.position = playerCamera.transform.position + playerCamera.transform.forward * distance;
            itemObject.transform.rotation = new Quaternion( 0.0f, playerCamera.transform.rotation.y, 0.0f, playerCamera.transform.rotation.w );
        }

    }

    // Start constructing an item
    public void StartConstructingItem ( Item item ) {
        Object itemPrefab = Resources.Load( "Prefabs/" + item.prefabName );

        itemObject = (GameObject)Instantiate( itemPrefab );
    }

}

这篇关于将物体放置在相机前面的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！