Unity3D让BoxCollider根据子物体生成自适应大小

news2024/10/5 15:43:47

系列文章目录

unity工具

文章目录

系列文章目录
- unity工具
👉前言
👉一、编辑器添加
👉二、代码动态添加的方法(第一种)
👉三、代码动态添加的方法(第二种)
👉四、重新设置模型的中心点
👉壁纸分享
👉总结

👉前言

大家好，我是心疼你的一切，不定时更新Unity开发技巧，觉得有用记得一键三连哦。
有时候我们需要用到不规则的物体,或者一大堆物体,又不想每一个物体都加上碰撞盒,所以这时候就需要把这些物体放在空物体里面,在空物体上添加根据子物体的网格生成自适应大小的碰撞盒
以下就是有编辑操作的,也可以代码生成之后操作的,具体使用看自己心情哦

提示：以下是本篇文章正文内容，下面案例可供参考

👉一、编辑器添加

1.一个空物体下面有若干个子物体,想要为空物体添加碰撞盒且碰撞盒还得要包裹所有子物体,手动拖动的话有点费时,费力,费眼,这时候有个工具是最好用的(如下图所示)
在这里插入图片描述
2.选中空物体点击(如下图所示)

3.点完之后的图(如下图所示)

点完之后就能看到一个全包围模型的碰撞盒,实现完成
实现如上效果需要一个编辑器脚本,脚本放在Editor文件夹下面
编辑器脚本如下

using UnityEngine;
using UnityEditor;
/// <summary>
/// 选择一个物体给当前物体添加自适应碰撞盒 编辑器脚本
/// </summary>
public class BoundsTool
{
    [MenuItem("Tools/添加自适应碰撞盒")]
    private static void AutoBoxCollider()
    {
        //如果未选中任何物体 返回
        GameObject gameObject = Selection.activeGameObject;
        if (gameObject == null) return;
        //计算中心点
        Vector3 center = Vector3.zero;
        var renders = gameObject.GetComponentsInChildren<Renderer>();
        for (int i = 0; i < renders.Length; i++)
        {
            center += renders[i].bounds.center;
        }
        center /= renders.Length;
        //创建边界盒
        Bounds bounds = new Bounds(center, Vector3.zero);
        foreach (var render in renders)
        {
            bounds.Encapsulate(render.bounds);
        }
        //先判断当前是否有碰撞器 进行销毁
        var currentCollider = gameObject.GetComponent<Collider>();
        if (currentCollider != null) Object.DestroyImmediate(currentCollider);
        //添加BoxCollider 设置中心点及大小
        var boxCollider = gameObject.AddComponent<BoxCollider>();
        boxCollider.center = bounds.center - gameObject.transform.position;
        boxCollider.size = bounds.size;
    }
}

👉二、代码动态添加的方法(第一种)

1.动态生成物体的时候,也是可以添加的
代码动态添加的第一种方法

/// <summary>
    /// 自动调节碰撞盒的大小
    /// </summary>
    /// <param name="obj_"></param>
    public void AutoBoxCollider(GameObject obj_)
    {
        //如果未选中任何物体 返回
        GameObject gameObject = obj_;
        if (gameObject == null) return;
        //计算中心点
        Vector3 center = Vector3.zero;
        var renders = gameObject.GetComponentsInChildren<Renderer>();
        for (int i = 0; i < renders.Length; i++)
        {
            center += renders[i].bounds.center;
        }
        center /= renders.Length;
        //创建边界盒
        Bounds bounds = new Bounds(center, Vector3.zero);
        foreach (var render in renders)
        {
            bounds.Encapsulate(render.bounds);
        }
        //先判断当前是否有碰撞器 进行销毁
        var currentCollider = gameObject.GetComponent<Collider>();
        if (currentCollider != null) UnityEngine.Object.DestroyImmediate(currentCollider);
        //添加BoxCollider 设置中心点及大小
        var boxCollider = gameObject.AddComponent<BoxCollider>();
        if (!gameObject.GetComponent<Highlighter>())
        {
            gameObject.AddComponent<Highlighter>();          
        }    
        boxCollider.center = bounds.center - gameObject.transform.position;
        boxCollider.size = bounds.size;
    }

结果就自行测试吧,我就不贴图片了

👉三、代码动态添加的方法(第二种)

调用方法如下

MeshTool.SpawnCollider(parents); //传一个父物体即可

代码如下

using UnityEngine;

public class MeshTool
{

    public static Bounds SpawnCollider(Transform target)
    {
        Vector3 pMax = Vector3.zero;
        Vector3 pMin = Vector3.zero;
        Vector3 center = Vector3.zero;

        Vector3 oldPos = target.transform.position;
        Quaternion oldQua = target.transform.rotation;
        Vector3 oldScale = target.transform.localScale;

        target.transform.position = Vector3.zero;
        target.transform.rotation = Quaternion.identity;
        target.transform.localScale = Vector3.one;

        Bounds bounds = CalcBounds(target, ref pMax, ref pMin, ref center);

        BoxCollider collider = target.GetComponent<BoxCollider>();
        if (collider == null)
        {
            collider = target.gameObject.AddComponent<BoxCollider>();
        }
        collider.center = bounds.center;
        collider.size = bounds.size;

        target.transform.position = oldPos;
        target.transform.rotation = oldQua;
        target.transform.localScale = oldScale;

        return bounds;
    }

    private static Bounds CalcBounds(Transform obj, ref Vector3 pMax, ref Vector3 pMin, ref Vector3 center)
    {
        Renderer meshRenderer = obj.GetComponent<Renderer>();

        if (meshRenderer != null)
        {
            Bounds b = meshRenderer.bounds;
            pMax = b.max;
            pMin = b.min;
            center = b.center;
        }

        RecursivelyCalcBounds(obj.transform, ref pMax, ref pMin);

        CalculateCenter(pMax, pMin, out center, ref pMax, ref pMin);

        Vector3 size = new Vector3(pMax.x - pMin.x, pMax.y - pMin.y, pMax.z - pMin.z);
        Bounds bound = new Bounds(center, size);

        return bound;
    }

    private static void CalculateCenter(Vector3 max, Vector3 min, out Vector3 center, ref Vector3 pMax, ref Vector3 pMin)
    {
        float xc = (pMax.x + pMin.x) / 2f;
        float yc = (pMax.y + pMin.y) / 2f;
        float zc = (pMax.z + pMin.z) / 2f;

        center = new Vector3(xc, yc, zc);
    }

    private static void RecursivelyCalcBounds(Transform obj, ref Vector3 pMax, ref Vector3 pMin)
    {
        if (obj.transform.childCount <= 0)
        {
            return;
        }

        foreach (Transform item in obj)
        {
            Renderer m = item.GetComponent<Renderer>();

            if (m != null)
            {
                Bounds b = m.bounds;
                if (pMax.Equals(Vector3.zero) && pMin.Equals(Vector3.zero))
                {
                    pMax = b.max;
                    pMin = b.min;
                }

                if (b.max.x > pMax.x)
                {
                    pMax.x = b.max.x;
                }

                if (b.max.y > pMax.y)
                {
                    pMax.y = b.max.y;
                }
                if (b.max.z > pMax.z)
                {
                    pMax.z = b.max.z;
                }
                if (b.min.x < pMin.x)
                {
                    pMin.x = b.min.x;
                }

                if (b.min.y < pMin.y)
                {
                    pMin.y = b.min.y;
                }
                if (b.min.z < pMin.z)
                {
                    pMin.z = b.min.z;
                }
            }
            RecursivelyCalcBounds(item, ref pMax, ref pMin);
        }
    }

}

👉四、重新设置模型的中心点

有时候模型的轴向不准确,就需要重新设置模型的轴向了,
有时候有多个子物体的时候,想要把轴向设置到模型的中心点,这个时候就可以用了,反正只要能代码添加的,绝对不会手动添加的
能懒就懒,能不动就不动,哈哈哈…

代码方法如下

List<GameObject> ObjZ = new List<GameObject>();
    Vector3 posZ = Vector3.zero;
    /// <summary>
    /// 设置模型的中心点,方便做模型的移动
    /// </summary>
    /// <param name="_trans"></param>
    public void SetModelPos(Transform _trans)
    {
        yield return new WaitForSeconds(0.2f);
        posZ = Vector3.zero;
        ObjZ.Clear();
        for (int i = 0; i < _trans.childCount; i++)
        {
            posZ += (_trans.GetChild(i).GetComponent<MeshCollider>().bounds.center);
            ObjZ.Add(_trans.GetChild(i).gameObject);
        }
        posZ /= _trans.childCount;
        for (int i = 0; i < ObjZ.Count; i++)
        {
            ObjZ[i].transform.parent = null;
        }
        _trans.position = posZ;
        for (int i = 0; i < ObjZ.Count; i++)
        {
            ObjZ[i].transform.parent = _trans;
        }     
    }