using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class CombineBones : MonoBehaviour {

    public GameObject bone;
    public List<GameObject> models = new List<GameObject>();
    public GameObject human;

	// Use this for initialization
	void Start () {
        human = GameObject.Instantiate<GameObject>(bone);
        human.SetActive(true);
        bone.SetActive(false);

        // 这种是合并网格
        addPart2();
        // 这种是组合网格。只是把模型挂到骨骼里，并替换模型的骨骼
        // addPart3()
	}

    void addPart2()
    {
        var bones = getAllChildTransform(human.transform);
        List<Material> mats = new List<Material>();
        List<Transform> newBones = new List<Transform>();
        List<CombineInstance> combineInstances = new List<CombineInstance>();

        foreach (var go in models)
        {
            var smrs = go.GetComponentsInChildren<SkinnedMeshRenderer>();
            foreach (var smr in smrs)
            {
                foreach (var b1 in smr.bones)
                {
                    Transform finded = null;
                    foreach (var b in bones)
                        if (b1.name == b.name)
                        {
                            finded = b;
                            break;
                        }
                    if (finded != null)
                    {
                        newBones.Add(finded);
                    }
                    else
                    {
                        Debug.LogError("Can not find bone " + b1.name);
                    }
                }
                mats.AddRange(smr.sharedMaterials);

                for (int sub = 0; sub < smr.sharedMesh.subMeshCount; ++sub)
                {
                    var ci = new CombineInstance();
                    ci.mesh = smr.sharedMesh;
                    ci.subMeshIndex = sub;
                    ci.transform = smr.transform.localToWorldMatrix;
                    combineInstances.Add(ci);
                }
            }
        }

        var humanSMR = human.AddComponent<SkinnedMeshRenderer>();
        humanSMR.materials = mats.ToArray();
        humanSMR.sharedMesh = new Mesh();
        humanSMR.sharedMesh.CombineMeshes(combineInstances.ToArray(), false, false);
        humanSMR.sharedMesh.Optimize();
        humanSMR.bones = newBones.ToArray();
    }

    void addPart3()
    {
        foreach (var go in models)
        {
            var smrs = go.GetComponentsInChildren<SkinnedMeshRenderer>();
            foreach (var smr in smrs)
            {
                var originSmr = GameObject.Instantiate<SkinnedMeshRenderer>(smr);
                var bones = getAllChildTransform(human.transform);


                originSmr.transform.parent = human.transform;
                originSmr.transform.localPosition = originSmr.transform.localPosition;
                originSmr.transform.localScale = originSmr.transform.localScale;
                originSmr.transform.localRotation = originSmr.transform.localRotation;

                List<Transform> newBones = new List<Transform>();
                foreach (var b1 in originSmr.bones)
                {
                    Transform finded = null;
                    foreach (var b in bones)
                        if (b1.name == b.name)
                        {
                            finded = b;
                            break;
                        }
                    if (finded != null)
                    {
                        newBones.Add(finded);
                    }
                    else
                    {
                        Debug.LogError("Can not find bone " + b1.name);
                    }
                }
                originSmr.bones = newBones.ToArray();
            }
        }
    }

    Transform[] getAllChildTransform(Transform t)
    {
        List<Transform> ts = new List<Transform>();
        _getAllChildTransform(t, ts);
        return ts.ToArray();
    }

    void _getAllChildTransform(Transform t, List<Transform> ts)
    {
        for (int i = 0; i < t.childCount; ++i)
        {
            ts.Add(t.GetChild(i));
            _getAllChildTransform(t.GetChild(i), ts);
        }
    }
}