riversong code showcase

Source/Riversong/Game/World/Buildings/Visualizations/BuildingUpgradeAnimation.cs

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+using Cysharp.Threading.Tasks;
+using UnityEngine;
+using UnityEngine.VFX;
+
+namespace DanieleMarotta.RiversongCodeShowcase
+{
+    public class BuildingUpgradeAnimation : MonoBehaviour
+    {
+        [SerializeField]
+        private VisualEffect _vfxPrefab;
+
+        [SerializeField]
+        private float _stretchDuration = 0.25f;
+
+        [SerializeField]
+        private float _stretchFactor = 1.2f;
+
+        [SerializeField]
+        private float _settleDuration = 0.75f;
+
+        [SerializeField]
+        private float _settleElasticity = 4.5f;
+
+        public async UniTask PlayAsync(Building building)
+        {
+            var vfx = Instantiate(_vfxPrefab, transform.position, transform.rotation);
+            DustVfxProperties.Setup(vfx, 1, new Vector2(building.Rect.Width, building.Rect.Height));
+
+            var fromScale = transform.localScale;
+            var toScale = new Vector3(fromScale.x, fromScale.y * _stretchFactor, fromScale.z);
+
+            var elapsed = 0f;
+            while (elapsed < _stretchDuration)
+            {
+                elapsed += Time.unscaledDeltaTime;
+                var t = EaseOutBack(Mathf.Clamp01(elapsed / _stretchDuration));
+                transform.localScale = Vector3.LerpUnclamped(fromScale, toScale, t);
+                await UniTask.NextFrame();
+            }
+
+            elapsed = 0;
+            while (elapsed < _settleDuration)
+            {
+                elapsed += Time.unscaledDeltaTime;
+                var t = EaseOutElastic(Mathf.Clamp01(elapsed / _settleDuration), _settleElasticity);
+                transform.localScale = Vector3.LerpUnclamped(toScale, fromScale, t);
+                await UniTask.NextFrame();
+            }
+
+            transform.localScale = fromScale;
+        }
+
+        private static float EaseOutBack(float t)
+        {
+            const float c1 = 1.70158f;
+            const float c3 = c1 + 1;
+            return 1 + c3 * Mathf.Pow(t - 1, 3) + c1 * Mathf.Pow(t - 1, 2);
+        }
+
+        private static float EaseOutElastic(float t, float elasticity)
+        {
+            var c4 = 2 * Mathf.PI / elasticity;
+            return t switch
+            {
+                0 => 0,
+                1 => 1,
+                _ => Mathf.Pow(2, -10 * t) * Mathf.Sin((10 * t - 0.75f) * c4) + 1
+            };
+        }
+    }
+}