【Unity】スライダーを特定の位置にスナップ（吸着）させる方法

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using TMPro;

public class SliderSnap : MonoBehaviour, IPointerUpHandler
{
    public Slider slider;
    public TextMeshProUGUI positionTMP;

    [Header("スナップ設定")]
    public float[] snapPoints = new float[] { 0.5f, 0.2f }; // 正規化値(0~1)
    public float snapThreshold = 0.02f;

    void Start()
    {
        slider.onValueChanged.AddListener(OnValueChanged);
        UpdatePositionDisplay();
    }

    void OnDestroy()
    {
        slider.onValueChanged.RemoveListener(OnValueChanged);
    }

    void OnValueChanged(float value)
    {
        float snapped;
        if (TryGetSnapPoint(value, out snapped))
        {
            slider.onValueChanged.RemoveListener(OnValueChanged);
            slider.value = snapped;
            slider.onValueChanged.AddListener(OnValueChanged);
        }

        UpdatePositionDisplay();
    }

    public void OnPointerUp(PointerEventData eventData)
    {
        float snapped;
        if (!TryGetSnapPoint(slider.value, out snapped)) return;

        slider.onValueChanged.RemoveListener(OnValueChanged);
        slider.value = snapped;
        slider.onValueChanged.AddListener(OnValueChanged);

        UpdatePositionDisplay();
    }

    bool TryGetSnapPoint(float value, out float snapped)
    {
        snapped = value;
        if (snapPoints == null || snapPoints.Length == 0) return false;

        float minDist = float.MaxValue;
        float nearest = value;

        foreach (float point in snapPoints)
        {
            float dist = Mathf.Abs(value - point);
            if (dist < minDist)
            {
                minDist = dist;
                nearest = point;
            }
        }

        if (minDist < snapThreshold)
        {
            snapped = nearest;
            return true;
        }
        return false;
    }

    public string GetPositionText(float value)
    {
        float rounded = Mathf.Round(value * 100f) / 100f;
        return rounded.ToString("0.##");
    }

    void UpdatePositionDisplay()
    {
        if (positionTMP == null) return;
        positionTMP.text = GetPositionText(slider.value);
    }
}