Use SDL_GetKeyboardState instead of event polling

FNA-XNA · Dec 28, 2023 · 33aa4d0 · 33aa4d0
1 parent 5f5ac87
commit 33aa4d0
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Showing 3 changed files with 77 additions and 25 deletions.
diff --git a/src/FNAPlatform/FNAPlatform.cs b/src/FNAPlatform/FNAPlatform.cs
@@ -16,6 +16,7 @@
 using Microsoft.Xna.Framework.Audio;
 using Microsoft.Xna.Framework.Input;
 using Microsoft.Xna.Framework.Input.Touch;
+using SDL2;
 #endregion
 
 namespace Microsoft.Xna.Framework
@@ -112,6 +113,7 @@ static FNAPlatform()
 			GetGraphicsAdapters =		SDL2_FNAPlatform.GetGraphicsAdapters;
 			GetCurrentDisplayMode =		SDL2_FNAPlatform.GetCurrentDisplayMode;
 			GetKeyFromScancode =		SDL2_FNAPlatform.GetKeyFromScancode;
+			GetScancodeFromKey =		SDL2_FNAPlatform.GetScancodeFromKey;
 			IsTextInputActive =		SDL2_FNAPlatform.IsTextInputActive;
 			StartTextInput =		SDL2.SDL.SDL_StartTextInput;
 			StopTextInput =			SDL2.SDL.SDL_StopTextInput;
@@ -264,6 +266,9 @@ ref bool textInputSuppress
 		public delegate Keys GetKeyFromScancodeFunc(Keys scancode);
 		public static readonly GetKeyFromScancodeFunc GetKeyFromScancode;
 
+		public delegate SDL.SDL_Scancode GetScancodeFromKeyFunc(Keys key);
+		public static readonly GetScancodeFromKeyFunc GetScancodeFromKey;
+
 		public delegate bool IsTextInputActiveFunc();
 		public static readonly IsTextInputActiveFunc IsTextInputActive;
 

diff --git a/src/FNAPlatform/SDL2_FNAPlatform.cs b/src/FNAPlatform/SDL2_FNAPlatform.cs
@@ -954,53 +954,68 @@ ref bool textInputSuppress
 				if (evt.type == SDL.SDL_EventType.SDL_KEYDOWN)
 				{
 					Keys key = ToXNAKey(ref evt.key.keysym);
-					if (!Keyboard.keys.Contains(key))
+					if (key == Keys.LeftControl)
+					{
+						Keyboard.LeftControlDown = true;
+					}
+					else if (key == Keys.RightControl)
+					{
+						Keyboard.RightControlDown = true;
+					}
+
+					if (evt.key.repeat > 0)
 					{
-						Keyboard.keys.Add(key);
 						int textIndex;
 						if (FNAPlatform.TextInputBindings.TryGetValue(key, out textIndex))
 						{
-							textInputControlDown[textIndex] = true;
 							TextInputEXT.OnTextInput(FNAPlatform.TextInputCharacters[textIndex]);
 						}
-						else if ((Keyboard.keys.Contains(Keys.LeftControl) || Keyboard.keys.Contains(Keys.RightControl))
+						else if ((Keyboard.LeftControlDown || Keyboard.RightControlDown)
 							&& key == Keys.V)
 						{
-							textInputControlDown[6] = true;
 							TextInputEXT.OnTextInput(FNAPlatform.TextInputCharacters[6]);
-							textInputSuppress = true;
 						}
 					}
-					else if (evt.key.repeat > 0)
+					else
 					{
 						int textIndex;
 						if (FNAPlatform.TextInputBindings.TryGetValue(key, out textIndex))
 						{
+							textInputControlDown[textIndex] = true;
 							TextInputEXT.OnTextInput(FNAPlatform.TextInputCharacters[textIndex]);
 						}
-						else if ((Keyboard.keys.Contains(Keys.LeftControl) || Keyboard.keys.Contains(Keys.RightControl))
+						else if ((Keyboard.LeftControlDown || Keyboard.RightControlDown)
 							&& key == Keys.V)
 						{
+							textInputControlDown[6] = true;
 							TextInputEXT.OnTextInput(FNAPlatform.TextInputCharacters[6]);
+							textInputSuppress = true;
 						}
 					}
 				}
 				else if (evt.type == SDL.SDL_EventType.SDL_KEYUP)
 				{
 					Keys key = ToXNAKey(ref evt.key.keysym);
-					if (Keyboard.keys.Remove(key))
+
+					if (key == Keys.LeftControl)
 					{
-						int value;
-						if (FNAPlatform.TextInputBindings.TryGetValue(key, out value))
-						{
-							textInputControlDown[value] = false;
-						}
-						else if (((!Keyboard.keys.Contains(Keys.LeftControl) && !Keyboard.keys.Contains(Keys.RightControl)) && textInputControlDown[6])
-							|| key == Keys.V)
-						{
-							textInputControlDown[6] = false;
-							textInputSuppress = false;
-						}
+						Keyboard.LeftControlDown = false;
+					}
+					else if (key == Keys.RightControl)
+					{
+						Keyboard.RightControlDown = false;
+					}
+
+					int value;
+					if (FNAPlatform.TextInputBindings.TryGetValue(key, out value))
+					{
+						textInputControlDown[value] = false;
+					}
+					else if (((!Keyboard.LeftControlDown && !Keyboard.RightControlDown) && textInputControlDown[6])
+						|| key == Keys.V)
+					{
+						textInputControlDown[6] = false;
+						textInputSuppress = false;
 					}
 				}
 
@@ -1215,7 +1230,7 @@ ref bool textInputSuppress
 					}
 				}
 
-				else if (evt.type == SDL.SDL_EventType.SDL_TEXTEDITING) 
+				else if (evt.type == SDL.SDL_EventType.SDL_TEXTEDITING)
 				{
 					int bytes = MeasureStringLength(evt.edit.text);
 					if (bytes > 0)
@@ -2843,6 +2858,16 @@ public static Keys GetKeyFromScancode(Keys scancode)
 			return Keys.None;
 		}
 
+		public static SDL.SDL_Scancode GetScancodeFromKey(Keys key)
+		{
+			if (INTERNAL_xnaMap.TryGetValue((int) key, out SDL.SDL_Scancode scancode))
+			{
+				return scancode;
+			}
+
+			return SDL.SDL_Scancode.SDL_SCANCODE_UNKNOWN;
+		}
+
 		#endregion
 
 		#region Private Static Win32 WM_PAINT Interop

diff --git a/src/Input/Keyboard.cs b/src/Input/Keyboard.cs
@@ -25,9 +25,22 @@ public static class Keyboard
 		/// Returns the current keyboard state.
 		/// </summary>
 		/// <returns>Current keyboard state.</returns>
-		public static KeyboardState GetState()
+		public unsafe static KeyboardState GetState()
 		{
-			return new KeyboardState(keys);
+			// SDL_GetKeyboardState returns a pointer that does not need to be freed.
+			byte* state = (byte*) SDL2.SDL.SDL_GetKeyboardState(out int numkeys);
+
+			activeKeys.Clear();
+			foreach (Keys key in allKeys)
+			{
+				SDL2.SDL.SDL_Scancode scancode = FNAPlatform.GetScancodeFromKey(key);
+				if (state[(int) scancode] != 0)
+				{
+					activeKeys.Add(key);
+				}
+			}
+
+			return new KeyboardState(activeKeys);
 		}
 
 		/// <summary>
@@ -37,7 +50,7 @@ public static KeyboardState GetState()
 		/// <returns>Current keyboard state.</returns>
 		public static KeyboardState GetState(PlayerIndex playerIndex)
 		{
-			return new KeyboardState(keys);
+			return GetState();
 		}
 
 		#endregion
@@ -53,7 +66,16 @@ public static Keys GetKeyFromScancodeEXT(Keys scancode)
 
 		#region Internal Static Variables
 
-		internal static List<Keys> keys = new List<Keys>();
+		// Used for special copy-paste text input
+		internal static bool LeftControlDown = false;
+		internal static bool RightControlDown = false;
+
+		#endregion
+
+		#region Private Static Variables
+
+		private static Keys[] allKeys = (Keys[]) Enum.GetValues(typeof(Keys));
+		private static List<Keys> activeKeys = new List<Keys>();
 
 		#endregion
 	}