Delayed speed increase modifier

Scripts/Resources/Modifiers/DelayedSpeedIncreaseModifier.cs

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+using Cirno.Scripts.Actors;
+using Godot;
+
+namespace Cirno.Scripts.Resources.Modifiers;
+
+[GlobalClass] 
+public partial class DelayedSpeedIncreaseModifier : TimeModifier
+{
+    
+    [Export] public Tween.TransitionType TransitionType { get; set; } = Tween.TransitionType.Linear;
+    [Export] public Tween.EaseType EaseType { get; set; } = Tween.EaseType.InOut;
+    
+    [Export] public float Duration { get; set; } = 1.0f;
+    
+    public override void Update(Bullet bullet, double delta, double elapsed)
+    {
+        float easedValue = ApplyEasing(Value, elapsed);
+        bullet.Speed += easedValue;
+    } 
+    
+    private float ApplyEasing(float value, double time)
+    {
+        float t = Mathf.Clamp((float)time, 0f, 1f); // Ensure the value stays within range
+        return (float)Tween.InterpolateValue(0f, value, t, Duration, TransitionType, EaseType);
+    }
+}