[游戏开发]Unity 获取模型Bound中心点

using UnityEngine;

namespace MT_Exterensions
{
    public static class GameObjectExtensions
    {
        public static Bounds CalculatePreciseBounds(this GameObject gameObject)
        {
            Bounds bounds = new Bounds();
            bool flag = false;
            MeshFilter[] componentsInChildren1 = gameObject.GetComponentsInChildren<MeshFilter>();
            if (componentsInChildren1.Length != 0)
            {
                bounds = GetMeshBounds(componentsInChildren1[0].gameObject, componentsInChildren1[0].sharedMesh);
                flag = true;
                for (int index = 1; index < componentsInChildren1.Length; ++index)
                    bounds.Encapsulate(GetMeshBounds(componentsInChildren1[index].gameObject,
                        componentsInChildren1[index].sharedMesh));
            }

            SkinnedMeshRenderer[] componentsInChildren2 = gameObject.GetComponentsInChildren<SkinnedMeshRenderer>();
            if (componentsInChildren2.Length != 0)
            {
                Mesh mesh = new Mesh();
                if (!flag)
                {
                    componentsInChildren2[0].BakeMesh(mesh);
                    bounds = GetMeshBounds(componentsInChildren2[0].gameObject, mesh);
                }

                for (int index = 1; index < componentsInChildren2.Length; ++index)
                {
                    componentsInChildren2[index].BakeMesh(mesh);
                    bounds = GetMeshBounds(componentsInChildren2[index].gameObject, mesh);
                }

                Object.Destroy(mesh);
            }

            return bounds;
        }

        private static Bounds GetMeshBounds(GameObject gameObject, Mesh mesh)
        {
            Bounds bounds = new Bounds();
            Vector3[] vertices = mesh.vertices;
            if (vertices.Length != 0)
            {
                bounds = new Bounds(gameObject.transform.TransformPoint(vertices[0]), Vector3.zero);
                for (int index = 1; index < vertices.Length; ++index)
                    bounds.Encapsulate(gameObject.transform.TransformPoint(vertices[index]));
            }

            return bounds;
        }

        public static Bounds CalculateBounds(this GameObject gameObject, bool localSpace = false)
        {
            Vector3 position = gameObject.transform.position;
            Quaternion rotation = gameObject.transform.rotation;
            Vector3 localScale = gameObject.transform.localScale;
            if (localSpace)
            {
                gameObject.transform.position = Vector3.zero;
                gameObject.transform.rotation = Quaternion.identity;
                gameObject.transform.localScale = Vector3.one;
            }

            Bounds bounds1 = new Bounds();
            Renderer[] componentsInChildren = gameObject.GetComponentsInChildren<Renderer>();
            if (componentsInChildren.Length != 0)
            {
                Bounds bounds2 = componentsInChildren[0].bounds;
                bounds1.center = bounds2.center;
                bounds1.extents = bounds2.extents;
                for (int index = 1; index < componentsInChildren.Length; ++index)
                {
                    Bounds bounds3 = componentsInChildren[index].bounds;
                    bounds1.Encapsulate(bounds3);
                }
            }

            if (localSpace)
            {
                gameObject.transform.position = position;
                gameObject.transform.rotation = rotation;
                gameObject.transform.localScale = localScale;
            }

            return bounds1;
        }

        /// <summary>
        /// 获取模型的Bounds
        /// </summary>
        /// <param name="gameObject"></param>
        /// <returns></returns>
        public static Bounds CalculateModelBounds(GameObject gameObject)
        {
            Bounds bounds = gameObject.CalculateBounds(false);
            return bounds;
        }
    }
}