build image cache in cpp dispEngine

Services/RenderingService.cs

@@ -1,6 +1,7 @@
 using Hi.Disp;
 using Hi.Geom;
-using Hi.Native;
+using Microsoft.AspNetCore.SignalR;
+using Hi.Webapi.Hubs;
 using System.Collections.Concurrent;
 
 namespace Hi.Webapi.Services
@@ -16,21 +17,23 @@ namespace Hi.Webapi.Services
 		/// </summary>
 		public ConcurrentDictionary<string, DispEngine> EngineDictionary { get; } = new();
 		ILogger<RenderingService> Logger { get; }
+		IHubContext<RenderingHub> HubContext { get; }
 		private bool disposedValue;
 
-		public RenderingService(ILogger<RenderingService> logger)
+		public RenderingService(ILogger<RenderingService> logger, IHubContext<RenderingHub> hubContext)
         {
             Logger = logger;
+            HubContext = hubContext;
         }
 
-        /// <summary>
-        /// 創建或獲取一個 DispEngine 實例
-        /// </summary>
-        public DispEngine GetOrCreateEngine(string sessionId)
+		/// <summary>
+		/// Get Or Create an DispEngine.
+		/// </summary>
+		public DispEngine GetOrCreateEngine(string connectionId)
         {
-            return EngineDictionary.GetOrAdd(sessionId, id =>
+            return EngineDictionary.GetOrAdd(connectionId, id =>
             {
-                Logger.LogInformation($"創建新的 DispEngine，SessionId: {id}");
+                Logger.LogInformation($"Create new DispEngine，ConnectionId: {id}");
                 var engine = new DispEngine();
                 engine.BackgroundColor = new Vec3d(0.1, 0.1, 0.5);
                 engine.BackgroundOpacity = 0.1;
@@ -39,25 +42,38 @@ namespace Hi.Webapi.Services
         }
 
         /// <summary>
-        /// 移除指定的 DispEngine
+        /// Send image to specific client.
         /// </summary>
-        public bool RemoveEngine(string sessionId)
+        public async Task SendImageToClient(string connectionId, byte[] compressedData, int originalLength, int width, int height)
         {
-            if (EngineDictionary.TryRemove(sessionId, out var engine))
+            try
             {
-                Logger.LogInformation($"移除 DispEngine，SessionId: {sessionId}");
+                await HubContext.Clients.Client(connectionId).SendAsync("ImageUpdate", 
+                    compressedData, originalLength, width, height);
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError(ex, $"Failed to send image to client: {connectionId}");
+            }
+        }
+
+        /// <summary>
+        /// Remove DispEngine
+        /// </summary>
+        public bool RemoveEngine(string connectionId)
+        {
+            if (EngineDictionary.TryRemove(connectionId, out var engine))
+            {
+                Logger.LogInformation($"Remove DispEngine，ConnectionId: {connectionId}");
                 
                 try
                 {
-                    // 停止渲染
                     engine.IsVisible = false;
-                    
-                    // 釋放資源
                     engine.Dispose();
                 }
                 catch (Exception ex)
                 {
-                    Logger.LogError(ex, $"清理 DispEngine 時發生錯誤，SessionId: {sessionId}");
+                    Logger.LogError(ex, $"清理 DispEngine 時發生錯誤，ConnectionId: {connectionId}");
                 }
                 
                 return true;
@@ -65,10 +81,10 @@ namespace Hi.Webapi.Services
             return false;
         }
 
-        /// <summary>
-        /// 獲取當前活動的引擎數量
-        /// </summary>
-        public int GetActiveEngineCount() => EngineDictionary.Count;
+		/// <summary>
+		/// Get Active Engine Count.
+		/// </summary>
+		public int GetActiveEngineCount() => EngineDictionary.Count;
 		/// <inheritdoc/>
 		protected virtual void Dispose(bool disposing)
 		{
@@ -85,7 +101,7 @@ namespace Hi.Webapi.Services
                         }
                         catch (Exception ex)
                         {
-                            Logger.LogError(ex, $"Dispose 時清理引擎錯誤，SessionId: {kvp.Key}");
+                            Logger.LogError(ex, $"Dispose DispEngine Error，ConnectionId: {kvp.Key}");
                         }
                     }
                     EngineDictionary.Clear();
@@ -102,4 +118,4 @@ namespace Hi.Webapi.Services
 		}
         
     }
-} 
+}