From ef1a4488d07507d84e3e5e3a86a0a665cb80cbf7 Mon Sep 17 00:00:00 2001
From: the_fiddler <the_fiddler@ebc5dd9b-fb1d-0410-b6f8-d24c324e9604>
Date: Wed, 14 Oct 2009 21:50:40 +0000
Subject: [PATCH] Added support for setting the application (use SHGetFileInfo
 to retrieve the correct icon and set it when constructing a new window).

---
 Source/OpenTK/Platform/Windows/API.cs         | 69 +++++++++++++++++++
 Source/OpenTK/Platform/Windows/WinGLNative.cs | 38 +++++++++-
 2 files changed, 106 insertions(+), 1 deletion(-)

diff --git a/Source/OpenTK/Platform/Windows/API.cs b/Source/OpenTK/Platform/Windows/API.cs
index 7f32f831..94177295 100644
--- a/Source/OpenTK/Platform/Windows/API.cs
+++ b/Source/OpenTK/Platform/Windows/API.cs
@@ -61,6 +61,7 @@ namespace OpenTK.Platform.Windows
 
     using HRESULT = System.IntPtr;
 
+    using DWORD_PTR = System.IntPtr;
     using UINT_PTR = System.UIntPtr;
 
     using TIMERPROC = Functions.TimerProc;
@@ -1402,6 +1403,13 @@ namespace OpenTK.Platform.Windows
         public delegate void TimerProc(HWND hwnd, WindowMessage uMsg, UINT_PTR idEvent, DWORD dwTime);
 
         #endregion
+
+        #region Shell Functions
+
+        [DllImport("shell32.dll")]
+        public static extern DWORD_PTR SHGetFileInfo(LPCTSTR pszPath, DWORD dwFileAttributes, ref SHFILEINFO psfi, UINT cbFileInfo, ShGetFileIconFlags uFlags);
+
+        #endregion
     }
 
     #region --- Constants ---
@@ -2690,6 +2698,22 @@ namespace OpenTK.Platform.Windows
 
     #endregion
 
+    #region ShFileInfo
+
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
+    public struct SHFILEINFO
+    {
+        public IntPtr hIcon;
+        public int iIcon;
+        public uint dwAttributes;
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
+        public string szDisplayName;
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
+        public string szTypeName;
+    };
+
+    #endregion
+
     #endregion
 
     #region --- Enums ---
@@ -3933,6 +3957,51 @@ namespace OpenTK.Platform.Windows
 
     #endregion
 
+    #region ShGetFileIcon
+
+    [Flags]
+    enum ShGetFileIconFlags : int
+    {
+        /// <summary>get icon</summary>
+        Icon = 0x000000100,
+        /// <summary>get display name</summary>
+        DisplayName = 0x000000200,
+        /// <summary>get type name</summary>
+        TypeName = 0x000000400,
+        /// <summary>get attributes</summary>
+        Attributes = 0x000000800,
+        /// <summary>get icon location</summary>
+        IconLocation = 0x000001000,
+        /// <summary>return exe type</summary>
+        ExeType = 0x000002000,
+        /// <summary>get system icon index</summary>
+        SysIconIndex = 0x000004000,
+        /// <summary>put a link overlay on icon</summary>
+        LinkOverlay = 0x000008000,
+        /// <summary>show icon in selected state</summary>
+        Selected = 0x000010000,
+        /// <summary>get only specified attributes</summary>
+        Attr_Specified = 0x000020000,
+        /// <summary>get large icon</summary>
+        LargeIcon = 0x000000000,
+        /// <summary>get small icon</summary>
+        SmallIcon = 0x000000001,
+        /// <summary>get open icon</summary>
+        OpenIcon = 0x000000002,
+        /// <summary>get shell size icon</summary>
+        ShellIconSize = 0x000000004,
+        /// <summary>pszPath is a pidl</summary>
+        PIDL = 0x000000008,
+        /// <summary>use passed dwFileAttribute</summary>
+        UseFileAttributes = 0x000000010,
+        /// <summary>apply the appropriate overlays</summary>
+        AddOverlays = 0x000000020,
+        /// <summary>Get the index of the overlay in the upper 8 bits of the iIcon</summary>
+        OverlayIndex = 0x000000040,
+    }
+
+    #endregion
+
     #endregion
 
     #region --- Callbacks ---
diff --git a/Source/OpenTK/Platform/Windows/WinGLNative.cs b/Source/OpenTK/Platform/Windows/WinGLNative.cs
index e49ae776..118a329e 100644
--- a/Source/OpenTK/Platform/Windows/WinGLNative.cs
+++ b/Source/OpenTK/Platform/Windows/WinGLNative.cs
@@ -33,6 +33,7 @@ using System.Text;
 using OpenTK.Graphics;
 using OpenTK.Input;
 using System.Collections.Generic;
+using System.IO;
 
 namespace OpenTK.Platform.Windows
 {
@@ -126,6 +127,8 @@ namespace OpenTK.Platform.Windows
 
             keyboards.Add(keyboard);
             mice.Add(mouse);
+
+            Icon = GetApplicationIcon();
         }
 
         #endregion
@@ -539,6 +542,7 @@ namespace OpenTK.Platform.Windows
                 wc.Instance = Instance;
                 wc.WndProc = WindowProcedureDelegate;
                 wc.ClassName = ClassName;
+                wc.Icon = Icon != null ? Icon.Handle : IntPtr.Zero;
                 //wc.Background = Functions.GetStockObject(5);
                 ushort atom = Functions.RegisterClassEx(ref wc);
 
@@ -579,6 +583,35 @@ namespace OpenTK.Platform.Windows
 
         #endregion
 
+        #region GetApplicationIcon
+
+        // Gets the shell application icon for the executing process or the default icon, if not available.
+        Icon GetApplicationIcon()
+        {
+            IntPtr retval = IntPtr.Zero;
+            try
+            {
+                SHFILEINFO info = new SHFILEINFO();
+                info.szDisplayName = "";
+                info.szTypeName = "";
+
+                int cbFileInfo = Marshal.SizeOf(info);
+                ShGetFileIconFlags flags = ShGetFileIconFlags.Icon | ShGetFileIconFlags.SmallIcon | ShGetFileIconFlags.UseFileAttributes;
+                string path = System.Reflection.Assembly.GetEntryAssembly().CodeBase;
+
+                retval = Functions.SHGetFileInfo(path, 256, ref info, (uint)cbFileInfo, flags);
+                return Icon.FromHandle(info.hIcon);
+            }
+            catch
+            {
+                // Shallow exceptions and fall-back to default icon.
+                Debug.Print("SHGetFileInfo failed, return value: {0}", retval);
+                return null;
+            }
+        }
+
+        #endregion
+
         #endregion
 
         #region INativeWindow Members
@@ -714,8 +747,9 @@ namespace OpenTK.Platform.Windows
             }
             set
             {
-                Functions.SendMessage(window.WindowHandle, WindowMessage.SETICON, (IntPtr)1, icon == null ? IntPtr.Zero : value.Handle);
                 icon = value;
+                if (window.WindowHandle != IntPtr.Zero)
+                    Functions.SendMessage(window.WindowHandle, WindowMessage.SETICON, (IntPtr)1, icon == null ? IntPtr.Zero : value.Handle);
             }
         }
 
@@ -1077,6 +1111,8 @@ namespace OpenTK.Platform.Windows
                 {
                     // Safe to clean managed resources
                     DestroyWindow();
+                    if (Icon != null)
+                        Icon.Dispose();
                 }
                 else
                 {