手把手带你使用Paint in 3D和Photon撸一个在线涂鸦画板

我就是我 2023-09-30 11:45 21阅读 0赞

#### Paint in 3D ####

Paint in 3D用于在游戏内和编辑器里绘制所有物体。所有功能已经过深度优化，在WebGL、移动端、VR 以及更多平台用起来都非常好用！

它支持标准管线，以及 LWRP、HDRP 和 URP。通过使用GPU 加速，你的物体将以难以置信的速度被绘制。代码还经过深度优化来防止GC，和将所有绘制操作一起批次完成。

跟贴图系统不同，它是一个纹理绘制解决方案。这意味着你可以绘制你的物体上百万次，还是无帧率丢失，让你创作难以想象的游戏。

它在Unity应用商店上的售价是60美元，地址：[https://assetstore.unity.com/packages/tools/painting/paint-in-3d-26286][https_assetstore.unity.com_packages_tools_painting_paint-in-3d-26286]。

#### Photon ####

Photon中文翻译为“光子”，为有着15年服务器后端开发经验的德国Exit Games公司开发的高效，稳定，可拓展的网络引擎。为目前世界上用户最广泛，支持游戏类型最多的专业网络引擎之一，也是Unity应用商店里用户评价最高的网络组件。

世界多个知名游戏公司和工作室选用Photon作为其产品的网络支持引擎，其中包括WB华纳，Codemaster, 2K, Glu, 微软游戏工作室，史克威尔艾尼克斯，百代南梦宫，SandBox，雨神电竞等知名企业，也有许多工作室和新创企业正在了解和试用Photon之中。

它在Unity应用商店上有一个免费应用，地址：[https://assetstore.unity.com/packages/tools/network/pun-2-free-119922][https_assetstore.unity.com_packages_tools_network_pun-2-free-119922]。

当然，Photon需要注册账号、创建应用等操作才能使用，还不了解的同学可以去[官方网站][Link 1]查阅相关资料。

温馨提示：Photon的国外服务器在国内使用比较卡，所以最好去中国官网申请国内的服务器，申请地址：[https://vibrantlink.com/chinacloudapply/][https_vibrantlink.com_chinacloudapply]。

下面正式开始。

#### 创建工程 ####

使用Unity Hub创建一个3D项目，然后分别引入**Paint in 3D**和**Photon Unity Networking 2**，如下图：

![万猫学社.png][.png]

温馨提示：在引入Photon Unity Networking 2后，记得配置AppId。

#### 创建简易画板 ####

为了方便演示，我们创建一个Quad作为画板，然后为其添加P3dPaintable、P3dMaterialCloner和P3dPaintableTexture组件，使用它们的默认配置即可，如下图：

![万猫学社.png][.png 1]

然后，创建一个空的GameObject命名为`OneMorePaint`，然后向`OneMorePaint`添加P3dPaintSphere组件，修改P3dPaintSphere组件的Color为红色，其他配置保持默认不变，如下图：

![万猫学社.png][.png 2]

再向`OneMorePaint`添加P3dHitScreen组件，勾选上P3dHitScreen组件的ConnectHits，其他配置保持默认不变，如下图：

![万猫学社.png][.png 3]

这时候，创建简易画板就做好了，运行以后就可以画画了，如下图：

![万猫学社.png][.png 4]

只不过，还是个单机版，我们加上实时在线功能。

#### 连接PUN2服务器 ####

创建一个C\#脚本命名为`Launcher`，再创建一个空的GameObject命名为`LauncherGameObject`，把C\#脚本`Launcher`添加到`LauncherGameObject`中。

编辑C\#脚本`Launcher`为如下内容：

using Photon.Pun;
    using Photon.Realtime;
    using UnityEngine;
    
    namespace One.More
    {
        public class Launcher : MonoBehaviourPunCallbacks
        {
            #region Private Fields
            /// <summary>
            /// This client's version number. Users are separated from each other by gameVersion (which allows you to make breaking changes).
            /// </summary>
            string gameVersion = "1";
            /// <summary>
            /// Keep track of the current process. Since connection is asynchronous and is based on several callbacks from Photon,
            /// we need to keep track of this to properly adjust the behavior when we receive call back by Photon.
            /// Typically this is used for the OnConnectedToMaster() callback.
            /// </summary>
            bool isConnecting;
            #endregion
    
            void Start()
            {
                this.Connect();
            }
    
            #region MonoBehaviourPunCallbacks Callbacks
            public override void OnConnectedToMaster()
            {
                Debug.Log("PUN Basics Tutorial/Launcher: OnConnectedToMaster() was called by PUN");
                // we don't want to do anything if we are not attempting to join a room.
                // this case where isConnecting is false is typically when you lost or quit the game, when this level is loaded, OnConnectedToMaster will be called, in that case
                // we don't want to do anything.
                if (isConnecting)
                {
                    // #Critical: The first we try to do is to join a potential existing room. If there is, good, else, we'll be called back with OnJoinRandomFailed()
                    PhotonNetwork.JoinRandomRoom();
                    isConnecting = false;
                }
            }
            public override void OnDisconnected(DisconnectCause cause)
            {
                Debug.LogWarningFormat("PUN Basics Tutorial/Launcher: OnDisconnected() was called by PUN with reason {0}", cause);
                isConnecting = false;
            }
            public override void OnJoinRandomFailed(short returnCode, string message)
            {
                Debug.Log("PUN Basics Tutorial/Launcher:OnJoinRandomFailed() was called by PUN. No random room available, so we create one.\nCalling: PhotonNetwork.CreateRoom");
                // #Critical: we failed to join a random room, maybe none exists or they are all full. No worries, we create a new room.
                PhotonNetwork.CreateRoom(null, new RoomOptions());
            }
            public override void OnJoinedRoom()
            {
                Debug.Log("PUN Basics Tutorial/Launcher: OnJoinedRoom() called by PUN. Now this client is in a room.");
            }
            #endregion
    
            #region Public Methods
            /// <summary>
            /// Start the connection process.
            /// - If already connected, we attempt joining a random room
            /// - if not yet connected, Connect this application instance to Photon Cloud Network
            /// </summary>
            public void Connect()
            {
                // we check if we are connected or not, we join if we are , else we initiate the connection to the server.
                if (PhotonNetwork.IsConnected)
                {
                    // #Critical we need at this point to attempt joining a Random Room. If it fails, we'll get notified in OnJoinRandomFailed() and we'll create one.
                    PhotonNetwork.JoinRandomRoom();
                }
                else
                {
                    // #Critical, we must first and foremost connect to Photon Online Server.
                    isConnecting = PhotonNetwork.ConnectUsingSettings();
                    PhotonNetwork.GameVersion = gameVersion;
                }
            }
            #endregion
        }
    }

这时候，就可以连接到连接PUN2服务器了，运行以后我们可以看到如下日志：

![万猫学社.png][.png 5]

#### 实时在线同步 ####

向之前创建的`OneMorePaint`添加PhotonView组件，使用默认配置即可，如下图：

![万猫学社.png][.png 6]

创建一个C\#脚本命名为`OnlinePainting`，把C\#脚本`OnlinePainting`添加到`OneMorePaint`中。

编辑C\#脚本`OnlinePainting`为如下内容：

using PaintIn3D;
    using Photon.Pun;
    using UnityEngine;
    
    namespace One.More
    {
        public class OnlinePainting : MonoBehaviour, IHitPoint, IHitLine
        {
            private PhotonView photonView;
            private P3dPaintSphere paintSphere;
    
            void Start()
            {
                this.photonView = this.GetComponent<PhotonView>();
                this.paintSphere = this.GetComponent<P3dPaintSphere>();
            }
    
            public void HandleHitPoint(bool preview, int priority, float pressure, int seed, Vector3 position, Quaternion rotation)
            {
                if (preview)
                {
                    return;
                }
                if (this.photonView == null)
                {
                    Debug.LogError("PhotonView is not found.");
                    return;
                }
                this.photonView.RPC("HandleHitPointRpc", RpcTarget.Others, preview, priority, pressure, seed, position, rotation);
            }
    
            public void HandleHitLine(bool preview, int priority, float pressure, int seed, Vector3 position, Vector3 endPosition, Quaternion rotation, bool clip)
            {
                if (preview)
                {
                    return;
                }
                if (this.photonView == null)
                {
                    Debug.LogError("PhotonView is not found.");
                    return;
                }
                this.photonView.RPC("HandleHitLinetRpc", RpcTarget.Others, preview, priority, pressure, seed, position, endPosition, rotation, clip);
            }
    
            [PunRPC]
            public void HandleHitPointRpc(bool preview, int priority, float pressure, int seed, Vector3 position, Quaternion rotation)
            {
                if (this.paintSphere == null)
                {
                    Debug.LogError("P3dPaintSphere is not found.");
                    return;
                }
                this.paintSphere.HandleHitPoint(preview, priority, pressure, seed, position, rotation);
            }
    
            [PunRPC]
            public void HandleHitLinetRpc(bool preview, int priority, float pressure, int seed, Vector3 position, Vector3 endPosition, Quaternion rotation, bool clip)
            {
                if (this.paintSphere == null)
                {
                    Debug.LogError("P3dPaintSphere is not found.");
                    return;
                }
                this.paintSphere.HandleHitLine(preview, priority, pressure, seed, position, endPosition, rotation, clip);
            }
        }
    }

在线涂鸦画板就制作完成了，我们看看运行效果怎么样？

#### 运行效果 ####

构建以后，同时启动两个客户端，效果如下：

![万猫学社][b9b238597dce4f9cbd2449f4400c88c4.png]

当然，这只是简单的在线涂鸦画板，你还可以再此基础上添加更丰富的功能，比如：修改画笔颜色、修改画笔大小等等。

> 最后，谢谢你这么帅，还给我**点赞**和**关注**。

[https_assetstore.unity.com_packages_tools_painting_paint-in-3d-26286]: https://assetstore.unity.com/packages/tools/painting/paint-in-3d-26286
[https_assetstore.unity.com_packages_tools_network_pun-2-free-119922]: https://assetstore.unity.com/packages/tools/network/pun-2-free-119922
[Link 1]: https://doc.photonengine.com/en-us/pun/current/getting-started/pun-intro
[https_vibrantlink.com_chinacloudapply]: https://vibrantlink.com/chinacloudapply/
[.png]: https://img-blog.csdnimg.cn/2e152cbfb4714e588f29d8d11c6b5d4b.png
[.png 1]: https://img-blog.csdnimg.cn/041cb4528b1349b4b1a9345838127481.png
[.png 2]: https://img-blog.csdnimg.cn/bfc5e73530be4d56baa1fae18b633477.png
[.png 3]: https://img-blog.csdnimg.cn/5335b11e06d849a598811efa45ee1283.png
[.png 4]: https://img-blog.csdnimg.cn/b477a169808847948783eb906bbf5443.png
[.png 5]: https://img-blog.csdnimg.cn/777136b860a74731888b64a870c16759.png
[.png 6]: https://img-blog.csdnimg.cn/c6b45b8988d549fda35ccf9582053fcb.png
[b9b238597dce4f9cbd2449f4400c88c4.png]: https://img-blog.csdnimg.cn/b9b238597dce4f9cbd2449f4400c88c4.png