Re-implement recoil (#9406)

* Re-implement recoil

Playing around with the values atm

* Update constants

* final tweaks

Content.Client/Camera/CameraRecoilSystem.cs

@@ -0,0 +1,32 @@
+using Content.Shared.Camera;
+
+namespace Content.Client.Camera;
+
+public sealed class CameraRecoilSystem : SharedCameraRecoilSystem
+{
+    public override void Initialize()
+    {
+        base.Initialize();
+        SubscribeNetworkEvent<CameraKickEvent>(OnCameraKick);
+    }
+
+    private void OnCameraKick(CameraKickEvent ev)
+    {
+        KickCamera(ev.Euid, ev.Recoil);
+    }
+
+    public override void KickCamera(EntityUid uid, Vector2 recoil, CameraRecoilComponent? component = null)
+    {
+        if (!Resolve(uid, ref component, false)) return;
+
+        // Use really bad math to "dampen" kicks when we're already kicked.
+        var existing = component.CurrentKick.Length;
+        var dampen = existing / KickMagnitudeMax;
+        component.CurrentKick += recoil * (1 - dampen);
+
+        if (component.CurrentKick.Length > KickMagnitudeMax)
+            component.CurrentKick = component.CurrentKick.Normalized * KickMagnitudeMax;
+
+        component.LastKickTime = 0;
+    }
+}