Lavaland chasms (#19154)

Content.Client/Chasm/ChasmFallingVisualsSystem.cs

@@ -0,0 +1,74 @@
+using Content.Shared.Chasm;
+using Robust.Client.Animations;
+using Robust.Client.GameObjects;
+using Robust.Shared.Animations;
+
+namespace Content.Client.Chasm;
+
+/// <summary>
+///     Handles the falling animation for entities that fall into a chasm.
+/// </summary>
+public sealed class ChasmFallingVisualsSystem : EntitySystem
+{
+    [Dependency] private readonly AnimationPlayerSystem _anim = default!;
+
+    private readonly string _chasmFallAnimationKey = "chasm_fall";
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<ChasmFallingComponent, ComponentInit>(OnComponentInit);
+        SubscribeLocalEvent<ChasmFallingComponent, ComponentRemove>(OnComponentRemove);
+    }
+
+    private void OnComponentInit(EntityUid uid, ChasmFallingComponent component, ComponentInit args)
+    {
+        if (!TryComp<SpriteComponent>(uid, out var sprite))
+            return;
+
+        component.OriginalScale = sprite.Scale;
+
+        var player = EnsureComp<AnimationPlayerComponent>(uid);
+        if (_anim.HasRunningAnimation(player, _chasmFallAnimationKey))
+            return;
+
+        _anim.Play(player, GetFallingAnimation(component), _chasmFallAnimationKey);
+    }
+
+    private void OnComponentRemove(EntityUid uid, ChasmFallingComponent component, ComponentRemove args)
+    {
+        if (!TryComp<SpriteComponent>(uid, out var sprite))
+            return;
+
+        var player = EnsureComp<AnimationPlayerComponent>(uid);
+        if (_anim.HasRunningAnimation(player, _chasmFallAnimationKey))
+            _anim.Stop(player, _chasmFallAnimationKey);
+
+        sprite.Scale = component.OriginalScale;
+    }
+
+    private Animation GetFallingAnimation(ChasmFallingComponent component)
+    {
+        var length = component.AnimationTime;
+
+        return new Animation()
+        {
+            Length = length,
+            AnimationTracks =
+            {
+                new AnimationTrackComponentProperty()
+                {
+                    ComponentType = typeof(SpriteComponent),
+                    Property = nameof(SpriteComponent.Scale),
+                    KeyFrames =
+                    {
+                        new AnimationTrackProperty.KeyFrame(component.OriginalScale, 0.0f),
+                        new AnimationTrackProperty.KeyFrame(component.AnimationScale, length.Seconds),
+                    },
+                    InterpolationMode = AnimationInterpolationMode.Cubic
+                }
+            }
+        };
+    }
+}