From ea0c845eb07df70931ac85954e298a91717c7be5 Mon Sep 17 00:00:00 2001
From: "Stefanos A." <stapostol@gmail.com>
Date: Mon, 30 Sep 2013 14:20:33 +0200
Subject: [PATCH] Attempted to fix key modifier state

SDL2 does not report keydown and keyup events on modifiers keys until
you release them. Attempted to fix this using SDL_GetModifierState, but
this does not appear to work. Should hit upstream.
---
 Source/OpenTK/Platform/SDL2/Sdl2Keyboard.cs | 45 +++++++++++++++------
 1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/Source/OpenTK/Platform/SDL2/Sdl2Keyboard.cs b/Source/OpenTK/Platform/SDL2/Sdl2Keyboard.cs
index cf8426a9..20693083 100644
--- a/Source/OpenTK/Platform/SDL2/Sdl2Keyboard.cs
+++ b/Source/OpenTK/Platform/SDL2/Sdl2Keyboard.cs
@@ -40,9 +40,37 @@ namespace OpenTK.Platform.SDL2
             state.IsConnected = true;
         }
 
-        #region Public Members
+        #region Private Members
 
-        public void ProcessKeyboardEvent(SDL.SDL_KeyboardEvent e)
+        // Unfortunately, SDL does not report KeyDown events
+        // when a modifier (e.g. shift, alt, etc) is first pressed.
+        // It reports a keydown+keyup event pair when the modifier
+        // is *released* - which means that we cannot use modifiers
+        // for regular input (e.g. press control to fire a weapon.)
+        // For that reason, we should also poll the keyboard directly
+        // as necessary.
+        // Fixme: this does not appear to work as expected.
+        void UpdateModifiers()
+        {
+            SDL.SDL_Keymod mod = SDL.SDL_GetModState();
+
+            state.SetKeyState(Key.LAlt, (byte)SDL.SDL_Scancode.SDL_SCANCODE_LALT, (mod & SDL.SDL_Keymod.KMOD_LALT) != 0);
+            state.SetKeyState(Key.RAlt, (byte)SDL.SDL_Scancode.SDL_SCANCODE_RALT, (mod & SDL.SDL_Keymod.KMOD_RALT) != 0);
+            state.SetKeyState(Key.LControl, (byte)SDL.SDL_Scancode.SDL_SCANCODE_LCTRL, (mod & SDL.SDL_Keymod.KMOD_LCTRL) != 0);
+            state.SetKeyState(Key.RControl, (byte)SDL.SDL_Scancode.SDL_SCANCODE_RCTRL, (mod & SDL.SDL_Keymod.KMOD_RCTRL) != 0);
+            state.SetKeyState(Key.LShift, (byte)SDL.SDL_Scancode.SDL_SCANCODE_LSHIFT, (mod & SDL.SDL_Keymod.KMOD_LSHIFT) != 0);
+            state.SetKeyState(Key.RShift, (byte)SDL.SDL_Scancode.SDL_SCANCODE_RSHIFT, (mod & SDL.SDL_Keymod.KMOD_RSHIFT) != 0);
+            state.SetKeyState(Key.Menu, (byte)SDL.SDL_Scancode.SDL_SCANCODE_APPLICATION, (mod & SDL.SDL_Keymod.KMOD_GUI) != 0);
+            state.SetKeyState(Key.CapsLock, (byte)SDL.SDL_Scancode.SDL_SCANCODE_CAPSLOCK, (mod & SDL.SDL_Keymod.KMOD_CAPS) != 0);
+            state.SetKeyState(Key.NumLock, (byte)SDL.SDL_Scancode.SDL_SCANCODE_NUMLOCKCLEAR, (mod & SDL.SDL_Keymod.KMOD_NUM) != 0);
+            //state.SetKeyState(Key., (byte)SDL.SDL_Scancode.SDL_SCANCODE_MODE, (mod & SDL.SDL_Keymod.KMOD_MODE) != 0);
+        }
+
+        #endregion
+
+        #region Internal Members
+
+        internal void ProcessKeyboardEvent(SDL.SDL_KeyboardEvent e)
         {
             Key key;
             bool pressed = e.state != 0;
@@ -50,17 +78,6 @@ namespace OpenTK.Platform.SDL2
             {
                 state.SetKeyState(key, (byte)e.keysym.scancode, pressed);
             }
-
-            switch (e.keysym.mod)
-            {
-                case SDL.SDL_Keymod.KMOD_ALT:
-                    state.SetKeyState(Key.AltLeft, (byte)e.keysym.scancode, pressed);
-                    break;
-
-                case SDL.SDL_Keymod.KMOD_CAPS:
-                    state.SetKeyState(Key.CapsLock, (byte)e.keysym.scancode, pressed);
-                    break;
-            }
         }
 
         #endregion
@@ -69,11 +86,13 @@ namespace OpenTK.Platform.SDL2
 
         public KeyboardState GetState()
         {
+            //UpdateModifiers(); // Fixme
             return state;
         }
 
         public KeyboardState GetState(int index)
         {
+            //UpdateModifiers(); // Fixme
             if (index == 0)
                 return state;
             else