控制特效在UI上面

控制特效在UI上，需要改动两个地方：
1、渲染队列为透明
2、保证sorting layer正确
如下代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using UnityEngine.CFEventSystems;
namespace UnityEngine.CFUI
{
    public class CFParticleControl : UIBehaviour
    {
        [SerializeField]
        public int renderQueueOffset = 0;
        public int renderQueue = 3000;
        public Renderer[] renderers;
        public Canvas mCanvas;
        public CFRectMask2D mCurrentMask;
        private bool running = false;

        public void Render(bool reset = true, bool atOnce = false)
        {
            if (!isActiveAndEnabled) return;
            running = true;
            if (atOnce)
                Update();
        }


        private void ReInitialize()
        {
            renderers = GetRenderers();
            mCanvas = GetFatherCanvas();
            mCurrentMask = GetClippable();
        }


        private void RenderSorting()
        {
            if (mCanvas == null) return;
            if (renderers != null)
            {
                for (int i = 0; i < renderers.Length; ++i)
                {
                    renderers[i].sortingLayerID = mCanvas.sortingLayerID;
                    renderers[i].sortingLayerName = mCanvas.sortingLayerName;
                    renderers[i].sortingOrder = mCanvas.sortingOrder;
                    renderers[i].enabled = mCanvas.enabled;
                    if (Application.isPlaying)
                    {
                        InnterUpdate(renderers[i].material);
                    }
                    else
                    {
                        InnterUpdate(renderers[i].sharedMaterial);
                    }
                }
            }
        }

        private Renderer[] GetRenderers()
        {
            return transform.GetComponentsInChildren<Renderer>(true);
        }

        private Canvas GetFatherCanvas()
        {
            List<Canvas> list = ListPool<Canvas>.Get();
            transform.GetComponentsInParent(true, list);
            Canvas returnCanvas = null;
            if (list.Count > 0) returnCanvas = list[0];
            ListPool<Canvas>.Release(list);
            return returnCanvas;
        }


        private CFRectMask2D GetClippable()
        {
            List<CFRectMask2D> components = ListPool<CFRectMask2D>.Get();
            transform.GetComponentsInParent(true, components);
            CFRectMask2D mask = null;
            if (components.Count > 0) mask = components[0];
            ListPool<CFRectMask2D>.Release(components);
            return mask;
        }

        private void InnterUpdate(Material material)
        {
            if (material == null) return;
            if (material.renderQueue != renderQueue + renderQueueOffset)
            {
                material.renderQueue = renderQueue + renderQueueOffset;
            }
        }


        protected override void OnEnable()
        {
            base.OnEnable();
            Render(false);
        }

        protected override void OnDisable()
        {
            base.OnDisable();
            mCanvas = null;
            mCurrentMask = null;
            renderers = null;
        }

        private void Update()
        {
            if (!running) return;
            running = false;
            ReInitialize();
            RenderSorting();
            RenderClippable();
        }

        protected override void OnCanvasHierarchyChanged()
        {
            running = true;
        }


        protected override void OnRectTransformDimensionsChange()
        {
            running = true;
        }

        protected override void OnTransformParentChanged()
        {
            running = true;
        }

        protected override void OnDidApplyAnimationProperties()
        {
            running = true;
        }


        readonly Vector3[] corners = new Vector3[4];
        private Vector4 border = new Vector4();
        private void RenderClippable()
        {
            if (renderers == null) return;
            if (mCurrentMask == null)
            {
                for (int i = 0; i < renderers.Length; ++i)
                {
                    if (renderers[i].material == null) continue;
                    renderers[i].material.DisableKeyword("UNITY_UI_CLIP_RECT");
                    border.Set(0, 0, 0, 0);
                }
            }
            else
            {
                for (int i = 0; i < renderers.Length; ++i)
                {
                    if (renderers[i].material == null) continue;
                    mCurrentMask.rectTransform.GetWorldCorners(corners);
                    renderers[i].material.EnableKeyword("UNITY_UI_CLIP_RECT");
                    border.Set(corners[0].x, corners[0].y, corners[2].x, corners[2].y);
                }
            }
        }
    }
}

关键代码在：

renderers[i].sortingLayerID = mCanvas.sortingLayerID;
renderers[i].sortingLayerName = mCanvas.sortingLayerName;
renderers[i].sortingOrder = mCanvas.sortingOrder;

无论是使用mesh的特效，还是使用particleSystem的特效，最终获取render即可。
注意：PartcileSystem的render获取到的是ParticleSystemRender。但ParticleSystemRender是Render的子类，所以也能获取的到。