test/Assets/Joystick Pack/Scripts/Base/Joystick.cs

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;

public class Joystick : MonoBehaviour, IPointerDownHandler, IDragHandler, IPointerUpHandler
{
    public float Horizontal { get { return input.x; } }
    public float Vertical { get { return input.y; } }
    public Vector2 Direction { get { return input; } }

    public float HandleRange
    {
        get { return handleRange; }
        set { handleRange = Mathf.Abs(value); }
    }

    public float DeadZone
    {
        get { return deadZone; }
        set { deadZone = Mathf.Abs(value); }
    }

    public AxisOptions AxisOptions { get { return AxisOptions; } set { axisOptions = value; } }
    public bool SnapX { get { return snapX; } set { snapX = value; } }
    public bool SnapY { get { return snapY; } set { snapY = value; } }

    [SerializeField] private float handleRange = 1;
    [SerializeField] private float deadZone = 0;
    [SerializeField] private AxisOptions axisOptions = AxisOptions.Both;
    [SerializeField] private bool snapX = false;
    [SerializeField] private bool snapY = false;

    [SerializeField] protected RectTransform background = null;
    [SerializeField] private RectTransform handle = null;
    private RectTransform baseRect = null;

    private Canvas canvas;
    private Camera cam;

    private Vector2 input = Vector2.zero;
    private Vector2 previousSnappedInput = Vector2.zero;

    protected virtual void Start()
    {
        HandleRange = handleRange;
        DeadZone = deadZone;
        baseRect = GetComponent<RectTransform>();
        canvas = GetComponentInParent<Canvas>();
        if (canvas == null)
            Debug.LogError("The Joystick is not placed inside a canvas");

        Vector2 center = new Vector2(0.5f, 0.5f);
        background.pivot = center;
        handle.anchorMin = center;
        handle.anchorMax = center;
        handle.pivot = center;
        handle.anchoredPosition = Vector2.zero;
    }

    public virtual void OnPointerDown(PointerEventData eventData)
    {
        previousSnappedInput = Vector2.zero;
        OnDrag(eventData);
    }

    public void OnDrag(PointerEventData eventData)
    {
        cam = null;
        if (canvas.renderMode == RenderMode.ScreenSpaceCamera)
            cam = canvas.worldCamera;

        Vector2 position = RectTransformUtility.WorldToScreenPoint(cam, background.position);
        Vector2 radius = background.sizeDelta / 2;
        input = (eventData.position - position) / (radius * canvas.scaleFactor);
        FormatInput();
        HandleInput(input.magnitude, input.normalized, radius, cam);
        handle.anchoredPosition = input * radius * handleRange;

        // Send event when value changes significantly (for 360-degree smooth movement)
        Vector2 currentSnapped = new Vector2(SnapToDiscrete(input.x), SnapToDiscrete(input.y));
        if ((currentSnapped.x == -1 || currentSnapped.x == 1 || currentSnapped.y == -1 || currentSnapped.y == 1) &&
            currentSnapped != previousSnappedInput)
        {
            EventBus.Publish(new JoystickPressEvent());
        }
        else if (currentSnapped == Vector2.zero && previousSnappedInput != Vector2.zero) {
            EventBus.Publish(new JoystickRealeaseEvent());
        }
        previousSnappedInput = currentSnapped;
    }

    protected virtual void HandleInput(float magnitude, Vector2 normalised, Vector2 radius, Camera cam)
    {
        if (magnitude > deadZone)
        {
            // Normalize to ensure speed is always 1 (full speed) or 0 (no movement)
            // This keeps 360-degree direction but binary speed
            input = normalised;
        }
        else
            input = Vector2.zero;
    }

    private void FormatInput()
    {
        if (axisOptions == AxisOptions.Horizontal)
            input = new Vector2(input.x, 0f);
        else if (axisOptions == AxisOptions.Vertical)
            input = new Vector2(0f, input.y);
    }

    private Vector2 SnapTo8Directions(Vector2 input)
    {
        // Snap to 8 directions: N, NE, E, SE, S, SW, W, NW
        // Returns values of -1, 0, or 1 for each axis
        
        if (input.magnitude < 0.4f)
            return Vector2.zero;

        // Calculate angle in degrees (0 = up/North, 90 = right/East)
        float angle = Mathf.Atan2(input.x, input.y) * Mathf.Rad2Deg;
        
        // Normalize angle to 0-360
        if (angle < 0) angle += 360f;
        
        // Snap to 8 directions (every 45 degrees)
        // 0° = N, 45° = NE, 90° = E, 135° = SE, 180° = S, 225° = SW, 270° = W, 315° = NW
        float snappedAngle = Mathf.Round(angle / 45f) * 45f;
        
        // Convert back to direction vector
        float rad = snappedAngle * Mathf.Deg2Rad;
        Vector2 snapped = new Vector2(Mathf.Sin(rad), Mathf.Cos(rad));
        
        // Ensure values are exactly -1, 0, or 1
        snapped.x = Mathf.Round(snapped.x);
        snapped.y = Mathf.Round(snapped.y);
        
        return snapped;
    }

    private float SnapToDiscrete(float value)
    {
        // Snap to -1, 1, or 0 for 8-directional movement
        // Use a small threshold to ensure diagonal movement works
        const float threshold = 0.1f;
        if (Mathf.Abs(value) < threshold)
            return 0;
        return value > 0 ? 1 : -1;
    }

    private float SnapFloat(float value, AxisOptions snapAxis)
    {
        if (value == 0)
            return value;

        if (axisOptions == AxisOptions.Both)
        {
            float angle = Vector2.Angle(input, Vector2.up);
            if (snapAxis == AxisOptions.Horizontal)
            {
                if (angle < 22.5f || angle > 157.5f)
                    return 0;
                else
                    return (value > 0) ? 1 : -1;
            }
            else if (snapAxis == AxisOptions.Vertical)
            {
                if (angle > 67.5f && angle < 112.5f)
                    return 0;
                else
                    return (value > 0) ? 1 : -1;
            }
            return value;
        }
        else
        {
            if (value > 0)
                return 1;
            if (value < 0)
                return -1;
        }
        return 0;
    }

    public virtual void OnPointerUp(PointerEventData eventData)
    {
        input = Vector2.zero;
        handle.anchoredPosition = Vector2.zero;
        previousSnappedInput = Vector2.zero;

        EventBus.Publish(new JoystickRealeaseEvent());
    }

    protected Vector2 ScreenPointToAnchoredPosition(Vector2 screenPosition)
    {
        Vector2 localPoint = Vector2.zero;
        if (RectTransformUtility.ScreenPointToLocalPointInRectangle(baseRect, screenPosition, cam, out localPoint))
        {
            Vector2 pivotOffset = baseRect.pivot * baseRect.sizeDelta;
            return localPoint - (background.anchorMax * baseRect.sizeDelta) + pivotOffset;
        }
        return Vector2.zero;
    }
}

public enum AxisOptions { Both, Horizontal, Vertical }
public struct JoystickPressEvent { }
public struct JoystickRealeaseEvent { }