Use System.Runtime.Caching.MemoryCache

MapControl/MapControl.csproj

@@ -12,7 +12,8 @@
     <AssemblyName>MapControl</AssemblyName>
     <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
-    <TargetFrameworkProfile>Client</TargetFrameworkProfile>
+    <TargetFrameworkProfile>
+    </TargetFrameworkProfile>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <DebugSymbols>true</DebugSymbols>
@@ -22,6 +23,7 @@
     <DefineConstants>TRACE;DEBUG</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
     <DebugType>none</DebugType>
@@ -31,13 +33,14 @@
     </DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="PresentationCore" />
     <Reference Include="PresentationFramework" />
     <Reference Include="System" />
-    <Reference Include="System.configuration" />
     <Reference Include="System.Core" />
+    <Reference Include="System.Runtime.Caching" />
     <Reference Include="System.Xaml" />
     <Reference Include="WindowsBase" />
   </ItemGroup>

MapControl/TileImageLoader.cs

@@ -7,6 +7,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Net;
+using System.Runtime.Caching;
 using System.Threading;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
@@ -21,18 +22,20 @@ namespace MapControl
     public class TileImageLoader : DispatcherObject
     {
         public static string TileCacheFolder = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData), "MapControl Cache");
-        public static TimeSpan TileCacheExpiryAge = TimeSpan.FromDays(1);
+        public static TimeSpan TileCacheExpiryAge = TimeSpan.FromDays(1d);
 
+        private readonly TileLayer tileLayer;
         private readonly Queue<Tile> pendingTiles = new Queue<Tile>();
         private int numDownloads;
 
-        internal int MaxDownloads;
+        public TileImageLoader(TileLayer tileLayer)
-        internal string TileLayerName;
+        {
-        internal TileSource TileSource;
+            this.tileLayer = tileLayer;
+        }
 
         private bool IsCached
         {
-            get { return !string.IsNullOrEmpty(TileCacheFolder) && !string.IsNullOrEmpty(TileLayerName); }
+            get { return tileLayer.IsCached && !string.IsNullOrEmpty(TileCacheFolder); }
         }
 
         internal void StartDownloadTiles(ICollection<Tile> tiles)
@@ -51,26 +54,33 @@ namespace MapControl
         private void StartDownloadTilesAsync(object newTilesList)
         {
             List<Tile> newTiles = (List<Tile>)newTilesList;
+            List<Tile> expiredTiles = new List<Tile>(newTiles.Count);
 
             lock (pendingTiles)
             {
-                if (IsCached)
-                {
-                    List<Tile> expiredTiles = new List<Tile>(newTiles.Count);
-
                 newTiles.ForEach(tile =>
                 {
-                        bool cacheExpired;
+                    ImageSource image = GetMemoryCachedImage(tile);
-                        ImageSource image = GetCachedImage(tile, out cacheExpired);
+
+                    if (image == null && IsCached)
+                    {
+                        bool fileCacheExpired;
+                        image = GetFileCachedImage(tile, out fileCacheExpired);
+
+                        if (image != null)
+                        {
+                            SetMemoryCachedImage(tile, image);
+
+                            if (fileCacheExpired)
+                            {
+                                expiredTiles.Add(tile); // enqueue later
+                            }
+                        }
+                    }
 
                     if (image != null)
                     {
                         Dispatcher.BeginInvoke((Action)(() => tile.Image = image));
-
-                            if (cacheExpired)
-                            {
-                                expiredTiles.Add(tile); // enqueue later
-                            }
                     }
                     else
                     {
@@ -79,11 +89,6 @@ namespace MapControl
                 });
 
                 expiredTiles.ForEach(tile => pendingTiles.Enqueue(tile));
-                }
-                else
-                {
-                    newTiles.ForEach(tile => pendingTiles.Enqueue(tile));
-                }
 
                 DownloadNextTiles(null);
             }
@@ -91,10 +96,10 @@ namespace MapControl
 
         private void DownloadNextTiles(object o)
         {
-            while (pendingTiles.Count > 0 && numDownloads < MaxDownloads)
+            while (pendingTiles.Count > 0 && numDownloads < tileLayer.MaxDownloads)
             {
                 Tile tile = pendingTiles.Dequeue();
-                tile.Uri = TileSource.GetUri(tile.XIndex, tile.Y, tile.ZoomLevel);
+                tile.Uri = tileLayer.TileSource.GetUri(tile.XIndex, tile.Y, tile.ZoomLevel);
                 numDownloads++;
 
                 ThreadPool.QueueUserWorkItem(DownloadTileAsync, tile);
@@ -108,54 +113,73 @@ namespace MapControl
 
             if (image != null)
             {
+                SetMemoryCachedImage(tile, image);
+
                 Dispatcher.BeginInvoke((Action)(() => tile.Image = image));
             }
 
             lock (pendingTiles)
             {
-                tile.Uri = null;
                 numDownloads--;
                 DownloadNextTiles(null);
             }
         }
 
-        private ImageSource GetCachedImage(Tile tile, out bool expired)
+        private string MemoryCacheKey(Tile tile)
         {
-            string tileDir = TileDirectory(tile);
+            return string.Format("{0}/{1}/{2}/{3}", tileLayer.Name, tile.ZoomLevel, tile.XIndex, tile.Y);
+        }
+
+        private string CacheFilePath(Tile tile)
+        {
+            return string.Format("{0}.{1}",
+                Path.Combine(TileCacheFolder, tileLayer.Name, tile.ZoomLevel.ToString(), tile.XIndex.ToString(), tile.Y.ToString()),
+                tileLayer.ImageType);
+        }
+
+        private ImageSource GetMemoryCachedImage(Tile tile)
+        {
+            string key = MemoryCacheKey(tile);
+            ImageSource image = MemoryCache.Default.Get(key) as ImageSource;
+
+            if (image != null)
+            {
+                TraceInformation("{0} - Memory Cached", key);
+            }
+
+            return image;
+        }
+
+        private void SetMemoryCachedImage(Tile tile, ImageSource image)
+        {
+            MemoryCache.Default.Set(MemoryCacheKey(tile), image,
+                new CacheItemPolicy { SlidingExpiration = TimeSpan.FromMinutes(10d) });
+        }
+
+        private ImageSource GetFileCachedImage(Tile tile, out bool expired)
+        {
+            string path = CacheFilePath(tile);
             ImageSource image = null;
             expired = false;
 
-            try
+            if (File.Exists(path))
-            {
-                if (Directory.Exists(tileDir))
-                {
-                    string tilePath = Directory.GetFiles(tileDir, string.Format("{0}.*", tile.Y)).FirstOrDefault();
-
-                    if (tilePath != null)
             {
                 try
                 {
-                            using (Stream fileStream = File.OpenRead(tilePath))
+                    using (Stream fileStream = File.OpenRead(path))
                     {
                         image = BitmapFrame.Create(fileStream, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
                     }
 
-                            expired = File.GetLastWriteTime(tilePath) + TileCacheExpiryAge <= DateTime.Now;
+                    expired = File.GetLastWriteTime(path) + TileCacheExpiryAge <= DateTime.Now;
-
+                    TraceInformation(expired ? "{0} - File Cache Expired" : "{0} - File Cached", path);
-                            TraceInformation(expired ? "{0} - Cache Expired" : "{0} - Cached", tilePath);
                 }
                 catch (Exception exc)
                 {
-                            TraceWarning("{0} - {1}", tilePath, exc.Message);
+                    TraceWarning("{0} - {1}", path, exc.Message);
-                            File.Delete(tilePath);
+                    File.Delete(path);
                 }
             }
-                }
-            }
-            catch (Exception exc)
-            {
-                TraceWarning("{0} - {1}", tileDir, exc.Message);
-            }
 
             return image;
         }
@@ -180,17 +204,14 @@ namespace MapControl
                         {
                             responseStream.CopyTo(memoryStream);
                             memoryStream.Position = 0;
+                            image = BitmapFrame.Create(memoryStream, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
 
-                            BitmapDecoder decoder = BitmapDecoder.Create(memoryStream, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
+                            if (IsCached)
-                            image = decoder.Frames[0];
-
-                            string tilePath;
-
-                            if (IsCached && (tilePath = TilePath(tile, decoder)) != null)
                             {
-                                Directory.CreateDirectory(Path.GetDirectoryName(tilePath));
+                                string path = CacheFilePath(tile);
+                                Directory.CreateDirectory(Path.GetDirectoryName(path));
 
-                                using (Stream fileStream = File.OpenWrite(tilePath))
+                                using (Stream fileStream = File.OpenWrite(path))
                                 {
                                     memoryStream.Position = 0;
                                     memoryStream.CopyTo(fileStream);
@@ -221,43 +242,6 @@ namespace MapControl
             return image;
         }
 
-        private string TileDirectory(Tile tile)
-        {
-            return Path.Combine(TileCacheFolder, TileLayerName, tile.ZoomLevel.ToString(), tile.XIndex.ToString());
-        }
-
-        private string TilePath(Tile tile, BitmapDecoder decoder)
-        {
-            string extension;
-
-            if (decoder is PngBitmapDecoder)
-            {
-                extension = "png";
-            }
-            else if (decoder is JpegBitmapDecoder)
-            {
-                extension = "jpg";
-            }
-            else if (decoder is BmpBitmapDecoder)
-            {
-                extension = "bmp";
-            }
-            else if (decoder is GifBitmapDecoder)
-            {
-                extension = "gif";
-            }
-            else if (decoder is TiffBitmapDecoder)
-            {
-                extension = "tif";
-            }
-            else
-            {
-                return null;
-            }
-
-            return Path.Combine(TileDirectory(tile), string.Format("{0}.{1}", tile.Y, extension));
-        }
-
         private static void TraceWarning(string format, params object[] args)
         {
             System.Diagnostics.Trace.TraceWarning("[{0:00}] {1}", Thread.CurrentThread.ManagedThreadId, string.Format(format, args));
@@ -265,7 +249,7 @@ namespace MapControl
 
         private static void TraceInformation(string format, params object[] args)
         {
-            System.Diagnostics.Trace.TraceInformation("[{0:00}] {1}", Thread.CurrentThread.ManagedThreadId, string.Format(format, args));
+            //System.Diagnostics.Trace.TraceInformation("[{0:00}] {1}", Thread.CurrentThread.ManagedThreadId, string.Format(format, args));
         }
     }
 }

MapControl/TileLayer.cs

@@ -18,58 +18,32 @@ namespace MapControl
     [ContentProperty("TileSource")]
     public class TileLayer : DrawingVisual
     {
-        private readonly TileImageLoader tileImageLoader = new TileImageLoader();
+        private readonly TileImageLoader tileImageLoader;
         private readonly List<Tile> tiles = new List<Tile>();
-        private bool isCached = false;
-        private string name = string.Empty;
         private string description = string.Empty;
         private Int32Rect grid;
         private int zoomLevel;
 
         public TileLayer()
         {
+            tileImageLoader = new TileImageLoader(this);
             VisualEdgeMode = EdgeMode.Aliased;
             VisualTransform = new MatrixTransform();
+            Name = string.Empty;
+            ImageType = "png";
             MinZoomLevel = 1;
             MaxZoomLevel = 18;
             MaxDownloads = 8;
         }
 
-        public bool HasDarkBackground { get; set; }
+        public string Name { get; set; }
+        public string ImageType { get; set; }
+        public TileSource TileSource { get; set; }
         public int MinZoomLevel { get; set; }
         public int MaxZoomLevel { get; set; }
-
+        public int MaxDownloads { get; set; }
-        public int MaxDownloads
+        public bool IsCached { get; set; }
-        {
+        public bool HasDarkBackground { get; set; }
-            get { return tileImageLoader.MaxDownloads; }
-            set { tileImageLoader.MaxDownloads = value; }
-        }
-
-        public TileSource TileSource
-        {
-            get { return tileImageLoader.TileSource; }
-            set { tileImageLoader.TileSource = value; }
-        }
-
-        public bool IsCached
-        {
-            get { return isCached; }
-            set
-            {
-                isCached = value;
-                tileImageLoader.TileLayerName = isCached ? name : null;
-            }
-        }
-
-        public string Name
-        {
-            get { return name; }
-            set
-            {
-                name = value;
-                tileImageLoader.TileLayerName = isCached ? name : null;
-            }
-        }
 
         public string Description
         {
@@ -150,7 +124,7 @@ namespace MapControl
 
             tiles.Sort((t1, t2) => t1.ZoomLevel - t2.ZoomLevel);
 
-            System.Diagnostics.Trace.TraceInformation("{0} Tiles: {1}", tiles.Count, string.Join(", ", tiles.Select(t => t.ZoomLevel.ToString())));
+            //System.Diagnostics.Trace.TraceInformation("{0} Tiles: {1}", tiles.Count, string.Join(", ", tiles.Select(t => t.ZoomLevel.ToString())));
         }
 
         private void RenderTiles()

TestApplication/MainWindow.xaml

@@ -120,35 +120,30 @@
                 <ComboBox Name="tileLayerComboBox" ToolTip="Main Tile Layer" Margin="4,0,4,0" DisplayMemberPath="Name" SelectedIndex="0">
                     <ComboBox.Items>
                         <map:TileLayer Name="OpenStreetMap" Description="© {y} OpenStreetMap Contributors, CC-BY-SA"
-                                       TileSource="http://{c}.tile.openstreetmap.org/{z}/{x}/{y}.png"
+                                       TileSource="http://{c}.tile.openstreetmap.org/{z}/{x}/{y}.png" IsCached="False"/>
-                                       IsCached="False"/>
                         <map:TileLayer Name="OpenCycleMap" Description="OpenCycleMap - © {y} Andy Allen &amp; OpenStreetMap Contributors, CC-BY-SA"
-                                       TileSource="http://{c}.tile.opencyclemap.org/cycle/{z}/{x}/{y}.png"
+                                       TileSource="http://{c}.tile.opencyclemap.org/cycle/{z}/{x}/{y}.png" IsCached="False"/>
-                                       IsCached="False"/>
                         <map:TileLayer Name="OCM Transport" Description="OpenCycleMap Transport - © {y} Andy Allen &amp; OpenStreetMap Contributors, CC-BY-SA"
-                                       TileSource="http://{c}.tile2.opencyclemap.org/transport/{z}/{x}/{y}.png"
+                                       TileSource="http://{c}.tile2.opencyclemap.org/transport/{z}/{x}/{y}.png" IsCached="False"/>
-                                       IsCached="False"/>
                         <map:TileLayer Name="OCM Landscape" Description="OpenCycleMap Landscape - © {y} Andy Allen &amp; OpenStreetMap Contributors, CC-BY-SA"
-                                       TileSource="http://{c}.tile3.opencyclemap.org/landscape/{z}/{x}/{y}.png"
+                                       TileSource="http://{c}.tile3.opencyclemap.org/landscape/{z}/{x}/{y}.png" IsCached="False"/>
-                                       IsCached="False"/>
                         <map:TileLayer Name="MapQuest OSM" Description="MapQuest OSM - © {y} MapQuest &amp; OpenStreetMap Contributors"
-                                       TileSource="http://otile{n}.mqcdn.com/tiles/1.0.0/osm/{z}/{x}/{y}.png"
+                                       TileSource="http://otile{n}.mqcdn.com/tiles/1.0.0/osm/{z}/{x}/{y}.png" IsCached="False"/>
-                                       IsCached="False"/>
                         <!--<map:TileLayer Name="Google Maps" Description="Google Maps - © {y} Google"
                                        TileSource="http://mt{i}.google.com/vt/x={x}&amp;y={y}&amp;z={z}"
                                        IsCached="False" MaxZoomLevel="20"/>
                         <map:TileLayer Name="Google Images" Description="Google Maps - © {y} Google"
                                        TileSource="http://khm{i}.google.com/kh/v=113&amp;x={x}&amp;y={y}&amp;z={z}"
-                                       IsCached="False" MaxZoomLevel="20" HasDarkBackground="True"/>
+                                       ImageType="jpg" IsCached="False" MaxZoomLevel="20" HasDarkBackground="True"/>
                         <map:TileLayer Name="Bing Maps" Description="Bing Maps - © {y} Microsoft Corporation"
                                        TileSource="http://ecn.t{i}.tiles.virtualearth.net/tiles/r{q}.png?g=0&amp;stl=h"
                                        IsCached="False" MaxZoomLevel="20"/>
                         <map:TileLayer Name="Bing Images" Description="Bing Maps - © {y} Microsoft Corporation"
                                        TileSource="http://ecn.t{i}.tiles.virtualearth.net/tiles/a{q}.jpeg?g=0"
-                                       IsCached="False" MaxZoomLevel="20" HasDarkBackground="True"/>
+                                       ImageType="jpg" IsCached="False" MaxZoomLevel="20" HasDarkBackground="True"/>
                         <map:TileLayer Name="Bing Hybrid" Description="Bing Maps - © {y} Microsoft Corporation"
                                        TileSource="http://ecn.t{i}.tiles.virtualearth.net/tiles/h{q}.jpeg?g=0&amp;stl=h"
-                                       IsCached="False" MaxZoomLevel="20" HasDarkBackground="True"/>-->
+                                       ImageType="jpg" IsCached="False" MaxZoomLevel="20" HasDarkBackground="True"/>-->
                     </ComboBox.Items>
                 </ComboBox>
             </StackPanel>

TestApplication/TestApplication.csproj

@@ -11,7 +11,8 @@
     <RootNamespace>MapControlTestApp</RootNamespace>
     <AssemblyName>MapControlTestApp</AssemblyName>
     <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
-    <TargetFrameworkProfile>Client</TargetFrameworkProfile>
+    <TargetFrameworkProfile>
+    </TargetFrameworkProfile>
     <FileAlignment>512</FileAlignment>
     <ProjectTypeGuids>{60dc8134-eba5-43b8-bcc9-bb4bc16c2548};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
     <WarningLevel>4</WarningLevel>
@@ -25,6 +26,7 @@
     <DefineConstants>DEBUG;TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|x86' ">
     <PlatformTarget>x86</PlatformTarget>
@@ -34,6 +36,7 @@
     <DefineConstants>TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />