perf: 优化物品图显示缓存

src/MaaWpfGui/Helper/ItemListHelper.cs

@@ -14,6 +14,7 @@
 #nullable enable
 
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.IO;
 using System.Text.Json;
@@ -84,56 +85,80 @@ namespace MaaWpfGui.Helper
                 : itemId;
         }
 
+        private static readonly ConcurrentDictionary<string, BitmapSource?> _imageCache = new();
+
         /// <summary>
         /// 获取对应物品的图标 / Get the icon of the corresponding item
         /// </summary>
         /// <param name="itemId">物品 id / Item id</param>
         /// <returns>物品图片</returns>
-        public static BitmapImage? GetItemImage(string itemId)
+        public static BitmapSource? GetItemImage(string itemId)
         {
+            if (_imageCache.TryGetValue(itemId, out var cachedImage))
+            {
+                return cachedImage;
+            }
+
             var imagePath = Path.Combine(Environment.CurrentDirectory, $"resource/template/items/{itemId}.png");
             if (!File.Exists(imagePath))
             {
+                _imageCache.TryAdd(itemId, null);
                 return null;
             }
 
             try
             {
-                var bitmapImage = new BitmapImage(new(imagePath, UriKind.RelativeOrAbsolute));
-
-                var stride = bitmapImage.PixelWidth * ((bitmapImage.Format.BitsPerPixel + 7) / 8);
-                var pixelData = new byte[stride * bitmapImage.PixelHeight];
-                bitmapImage.CopyPixels(pixelData, stride, 0);
-
-                // 把黑边变成透明（其实是所有的黑色都变成透明了x
-                for (int i = 0; i < pixelData.Length; i += 4)
-                {
-                    if (pixelData[i] == 0 && pixelData[i + 1] == 0 && pixelData[i + 2] == 0)
-                    {
-                        pixelData[i + 3] = 0;
-                    }
-                }
-
-                // 不知道为啥 WriteableBitmap(bitmapImage); 得到的图没有透明度，大概是原始 uri 对应的是个 24 位的图？手动处理一下
-                var writeableBitmap = new WriteableBitmap(bitmapImage.PixelWidth, bitmapImage.PixelHeight, bitmapImage.DpiX, bitmapImage.DpiY, PixelFormats.Bgra32, null);
-                writeableBitmap.WritePixels(new(0, 0, bitmapImage.PixelWidth, bitmapImage.PixelHeight), pixelData, stride, 0);
-
-                bitmapImage = new();
-                using MemoryStream stream = new MemoryStream();
-                PngBitmapEncoder encoder = new PngBitmapEncoder();
-                encoder.Frames.Add(BitmapFrame.Create(writeableBitmap));
-                encoder.Save(stream);
-                bitmapImage.BeginInit();
-                bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
-                bitmapImage.StreamSource = stream;
-                bitmapImage.EndInit();
-                bitmapImage.Freeze();
-                return bitmapImage;
+                var processedImage = ProcessBlackToTransparent(imagePath);
+                _imageCache.TryAdd(itemId, processedImage);
+                return processedImage;
             }
             catch
             {
+                _imageCache.TryAdd(itemId, null);
                 return null;
             }
         }
+
+        private static BitmapSource ProcessBlackToTransparent(string imagePath)
+        {
+            var original = new BitmapImage();
+            original.BeginInit();
+            original.CacheOption = BitmapCacheOption.OnLoad;
+            original.UriSource = new(imagePath, UriKind.RelativeOrAbsolute);
+            original.EndInit();
+
+            var convertedBitmap = new FormatConvertedBitmap(original, PixelFormats.Bgra32, null, 0);
+            var writeable = new WriteableBitmap(convertedBitmap);
+
+            writeable.Lock();
+            try
+            {
+                unsafe
+                {
+                    var pixels = (uint*)writeable.BackBuffer;
+                    int pixelCount = writeable.PixelWidth * writeable.PixelHeight;
+
+                    for (int i = 0; i < pixelCount; i++)
+                    {
+                        uint pixel = pixels[i];
+                        uint bgr = pixel & 0x00FFFFFF;
+
+                        if (bgr == 0)
+                        {
+                            pixels[i] = 0x00000000;
+                        }
+                    }
+                }
+
+                writeable.AddDirtyRect(new(0, 0, writeable.PixelWidth, writeable.PixelHeight));
+            }
+            finally
+            {
+                writeable.Unlock();
+            }
+
+            writeable.Freeze();
+            return writeable;
+        }
     }
 }

src/MaaWpfGui/ViewModels/UI/RecognizerViewModel.cs

@@ -354,7 +354,7 @@ namespace MaaWpfGui.ViewModels.UI
 
             public string Id { get; set; } = null!;
 
-            public BitmapImage? Image { get; set; }
+            public BitmapSource? Image { get; set; }
 
             public string? Count { get; set; }
         }
@@ -398,11 +398,6 @@ namespace MaaWpfGui.ViewModels.UI
         /// </summary>
         public string LoliconResult { get; set; } = string.Empty;
 
-        /// <summary>
-        /// gets or sets the depot image.
-        /// </summary>
-        private static readonly Dictionary<string, BitmapImage?> _imageCache = new();
-
         /// <summary>
         /// parse of depot recognition result
         /// </summary>
@@ -430,17 +425,11 @@ namespace MaaWpfGui.ViewModels.UI
                     continue;
                 }
 
-                if (!_imageCache.TryGetValue(id, out var image))
-                {
-                    image = ItemListHelper.GetItemImage(id);
-                    _imageCache[id] = image;
-                }
-
                 DepotResultDate result = new()
                 {
                     Id = id,
                     Name = ItemListHelper.GetItemName(id),
-                    Image = image,
+                    Image = ItemListHelper.GetItemImage(id),
                     Count = item["have"] != null && int.TryParse(item["have"]?.ToString() ?? "-1", out int haveValue)
                         ? (haveValue > 10000
                             ? $"{haveValue / 10000.0:F1}w"