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。
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。
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/。
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：
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：
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：
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：
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：
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：
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：
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：
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、推荐和关注。