C# support for virtual joystick

addons/virtual_joystick/VirtualJoystickCS.cs

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+using Godot;
+using System;
+
+public partial class VirtualJoystickCS : Control
+{
+	[Export] public Color PressedColor = Colors.Gray;
+	[Export(PropertyHint.Range, "0,200,1")] public float DeadzoneSize = 10;
+	[Export(PropertyHint.Range, "0,500,1")] public float ClampzoneSize = 75;
+
+	public enum JoystickMode { FIXED, DYNAMIC, FOLLOWING }
+	[Export] public JoystickMode joystickMode = JoystickMode.FIXED;
+
+	public enum VisibilityMode { ALWAYS, TOUCHSCREEN_ONLY, WHEN_TOUCHED }
+	[Export] public VisibilityMode visibilityMode = VisibilityMode.ALWAYS;
+
+	[Export] public bool UseInputActions = true;
+	[Export] public string ActionLeft = "ui_left";
+	[Export] public string ActionRight = "ui_right";
+	[Export] public string ActionUp = "ui_up";
+	[Export] public string ActionDown = "ui_down";
+
+	public bool IsPressed = false;
+	public Vector2 Output = Vector2.Zero;
+
+	private int _touchIndex = -1;
+
+	private Control _base;
+	private Control _tip;
+
+	private Vector2 _baseDefaultPosition;
+	private Vector2 _tipDefaultPosition;
+	private Color _defaultColor;
+
+	public override void _Ready()
+	{
+		_base = GetNode<Control>("Base");
+		_tip = _base.GetNode<Control>("Tip");
+
+		_baseDefaultPosition = _base.Position;
+		_tipDefaultPosition = _tip.Position;
+		_defaultColor = _tip.Modulate;
+
+		if ((bool)ProjectSettings.GetSetting("input_devices/pointing/emulate_mouse_from_touch"))
+			GD.PrintErr("Set 'emulate_mouse_from_touch' to False");
+
+		if (!(bool)ProjectSettings.GetSetting("input_devices/pointing/emulate_touch_from_mouse"))
+			GD.PrintErr("Set 'emulate_touch_from_mouse' to True");
+
+		if (!DisplayServer.IsTouchscreenAvailable() && visibilityMode == VisibilityMode.TOUCHSCREEN_ONLY)
+			Hide();
+
+		if (visibilityMode == VisibilityMode.WHEN_TOUCHED)
+			Hide();
+	}
+
+	public override void _Input(InputEvent @event)
+	{
+		if (@event is InputEventScreenTouch touch)
+		{
+			if (touch.Pressed)
+			{
+				if (_IsPointInsideJoystickArea(touch.Position) && _touchIndex == -1)
+				{
+					if (joystickMode != JoystickMode.FIXED || _IsPointInsideBase(touch.Position))
+					{
+						if (joystickMode != JoystickMode.FIXED)
+							_MoveBase(touch.Position);
+
+						if (visibilityMode == VisibilityMode.WHEN_TOUCHED)
+							Show();
+
+						_touchIndex = touch.Index;
+						_tip.Modulate = PressedColor;
+						_UpdateJoystick(touch.Position);
+						GetViewport().SetInputAsHandled();
+					}
+				}
+			}
+			else if (touch.Index == _touchIndex)
+			{
+				_Reset();
+				if (visibilityMode == VisibilityMode.WHEN_TOUCHED)
+					Hide();
+				GetViewport().SetInputAsHandled();
+			}
+		}
+		else if (@event is InputEventScreenDrag drag && drag.Index == _touchIndex)
+		{
+			_UpdateJoystick(drag.Position);
+			GetViewport().SetInputAsHandled();
+		}
+	}
+
+	private void _MoveBase(Vector2 newPos)
+	{
+		_base.GlobalPosition = newPos - _base.PivotOffset * GetGlobalTransformWithCanvas().Scale;
+	}
+
+	private void _MoveTip(Vector2 newPos)
+	{
+		_tip.GlobalPosition = newPos - _tip.PivotOffset * _base.GetGlobalTransformWithCanvas().Scale;
+	}
+
+	private bool _IsPointInsideJoystickArea(Vector2 point)
+	{
+		var scale = GetGlobalTransformWithCanvas().Scale;
+		return point.X >= GlobalPosition.X && point.X <= GlobalPosition.X + (Size.X * scale.X)
+			&& point.Y >= GlobalPosition.Y && point.Y <= GlobalPosition.Y + (Size.Y * scale.Y);
+	}
+
+	private Vector2 _GetBaseRadius()
+	{
+		return _base.Size * _base.GetGlobalTransformWithCanvas().Scale / 2f;
+	}
+
+	private bool _IsPointInsideBase(Vector2 point)
+	{
+		var radius = _GetBaseRadius();
+		var center = _base.GlobalPosition + radius;
+		var diff = point - center;
+		return diff.LengthSquared() <= radius.X * radius.X;
+	}
+
+	private void _UpdateJoystick(Vector2 touchPos)
+	{
+		var radius = _GetBaseRadius();
+		var center = _base.GlobalPosition + radius;
+		var vector = touchPos - center;
+		vector = vector.LimitLength(ClampzoneSize);
+
+		if (joystickMode == JoystickMode.FOLLOWING && touchPos.DistanceTo(center) > ClampzoneSize)
+			_MoveBase(touchPos - vector);
+
+		_MoveTip(center + vector);
+
+		if (vector.LengthSquared() > DeadzoneSize * DeadzoneSize)
+		{
+			IsPressed = true;
+			Output = (vector - (vector.Normalized() * DeadzoneSize)) / (ClampzoneSize - DeadzoneSize);
+		}
+		else
+		{
+			IsPressed = false;
+			Output = Vector2.Zero;
+		}
+
+		if (UseInputActions)
+		{
+			// Release first
+			if (Output.X >= 0 && Input.IsActionPressed(ActionLeft)) Input.ActionRelease(ActionLeft);
+			if (Output.X <= 0 && Input.IsActionPressed(ActionRight)) Input.ActionRelease(ActionRight);
+			if (Output.Y >= 0 && Input.IsActionPressed(ActionUp)) Input.ActionRelease(ActionUp);
+			if (Output.Y <= 0 && Input.IsActionPressed(ActionDown)) Input.ActionRelease(ActionDown);
+
+			// Then press
+			if (Output.X < 0) Input.ActionPress(ActionLeft, -Output.X);
+			if (Output.X > 0) Input.ActionPress(ActionRight, Output.X);
+			if (Output.Y < 0) Input.ActionPress(ActionUp, -Output.Y);
+			if (Output.Y > 0) Input.ActionPress(ActionDown, Output.Y);
+		}
+	}
+
+	private void _Reset()
+	{
+		IsPressed = false;
+		Output = Vector2.Zero;
+		_touchIndex = -1;
+		_tip.Modulate = _defaultColor;
+		_base.Position = _baseDefaultPosition;
+		_tip.Position = _tipDefaultPosition;
+
+		if (UseInputActions)
+		{
+			foreach (string action in new[] { ActionLeft, ActionRight, ActionDown, ActionUp })
+			{
+				if (Input.IsActionPressed(action))
+					Input.ActionRelease(action);
+			}
+		}
+	}
+
+}