IGamepad: Add extension methods to return a Thumbstick (#1469)

* Start working on extension methods to return a Thumbstick

* Rename GamepadExtensions.First to FirstButton, add FirstThumbstick

* Add new Thumbstick and ThumbstickButton methods, deprecate old

* Add new extension methods to PublicAPI

I'm not entirely sure if this is correct, or what these files even are, really, but I feel this is probably what's expected.

* Move new methods to unshipped PublicAPI

* Remove FirstThumbstick method, document thrown exception

* Rename FirstButton back to First

Author: jvyden

src/Input/Silk.NET.Input.Common/GamepadExtensions.cs

@@ -71,12 +71,40 @@ private static Button First(IGamepad gamepad, ButtonName name) // now without th
         /// <summary>
         /// Gets the <see cref="ButtonName.LeftStick" /> button.
         /// </summary>
+        [Obsolete($"This method is obsolete! Use {nameof(LeftThumbstickButton)}")]
         public static Button LeftStick(this IGamepad gamepad) => First(gamepad, ButtonName.LeftStick);
 
         /// <summary>
         /// Gets the <see cref="ButtonName.RightStick" /> button.
         /// </summary>
+        [Obsolete($"This method is obsolete! Use {nameof(RightThumbstickButton)}")]
         public static Button RightStick(this IGamepad gamepad) => First(gamepad, ButtonName.RightStick);
+        
+        /// <summary>
+        /// Gets the left <see cref="Thumbstick"/>.
+        /// </summary>
+        /// <remarks>
+        /// If the input backend does not support this thumbstick, a <see cref="IndexOutOfRangeException"/> will be thrown.
+        /// </remarks>
+        public static Thumbstick LeftThumbstick(this IGamepad gamepad) => gamepad.Thumbsticks[0];
+        
+        /// <summary>
+        /// Gets the right <see cref="Thumbstick"/>.
+        /// </summary>
+        /// <remarks>
+        /// If the input backend does not support this thumbstick, a <see cref="IndexOutOfRangeException"/> will be thrown.
+        /// </remarks>
+        public static Thumbstick RightThumbstick(this IGamepad gamepad) => gamepad.Thumbsticks[1];
+        
+        /// <summary>
+        /// Gets the <see cref="ButtonName.LeftStick" /> button.
+        /// </summary>
+        public static Button LeftThumbstickButton(this IGamepad gamepad) => First(gamepad, ButtonName.LeftStick);
+
+        /// <summary>
+        /// Gets the <see cref="ButtonName.RightStick" /> button.
+        /// </summary>
+        public static Button RightThumbstickButton(this IGamepad gamepad) => First(gamepad, ButtonName.RightStick);
 
         /// <summary>
         /// Gets the <see cref="ButtonName.DPadUp" /> button.

src/Input/Silk.NET.Input.Common/PublicAPI/net5.0/PublicAPI.Unshipped.txt

@@ -1 +1,5 @@
 #nullable enable
+static Silk.NET.Input.GamepadExtensions.LeftThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.LeftThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button
+static Silk.NET.Input.GamepadExtensions.RightThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.RightThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button

src/Input/Silk.NET.Input.Common/PublicAPI/netcoreapp3.1/PublicAPI.Unshipped.txt

@@ -1 +1,5 @@
 #nullable enable
+static Silk.NET.Input.GamepadExtensions.LeftThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.LeftThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button
+static Silk.NET.Input.GamepadExtensions.RightThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.RightThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button

src/Input/Silk.NET.Input.Common/PublicAPI/netstandard2.0/PublicAPI.Unshipped.txt

@@ -1 +1,5 @@
 #nullable enable
+static Silk.NET.Input.GamepadExtensions.LeftThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.LeftThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button
+static Silk.NET.Input.GamepadExtensions.RightThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.RightThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button

src/Input/Silk.NET.Input.Common/PublicAPI/netstandard2.1/PublicAPI.Unshipped.txt

@@ -1 +1,5 @@
 #nullable enable
+static Silk.NET.Input.GamepadExtensions.LeftThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.LeftThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button
+static Silk.NET.Input.GamepadExtensions.RightThumbstick(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Thumbstick
+static Silk.NET.Input.GamepadExtensions.RightThumbstickButton(this Silk.NET.Input.IGamepad! gamepad) -> Silk.NET.Input.Button