Mirror: Thrown soap/banana/(etc?) will fail to slip until it lands (#280

)

## Mirror of PR #24494: [Thrown soap/banana/(etc?) will fail to slip
until it
lands](space-wizards/space-station-14#24494)
from <img src="https://avatars.githubusercontent.com/u/10567778?v=4"
alt="space-wizards" width="22"/>
[space-wizards](https://github.com/space-wizards)/[space-station-14](https://github.com/space-wizards/space-station-14)

###### `e061cb3f8c9dc8ddc26624ead2086dfb41465aae`

PR opened by <img
src="https://avatars.githubusercontent.com/u/35878406?v=4"
width="16"/><a href="https://github.com/Errant-4"> Errant-4</a> at
2024-01-25 00:04:36 UTC

---

PR changed 1 files with 21 additions and 1 deletions.

The PR had the following labels:
- Status: Awaiting Changes


---

<details open="true"><summary><h1>Original Body</h1></summary>

> ## About the PR
> Thrown objects can no longer slip until they have landed. For a
succesful slip, the attacker must now calculate how to throw the soap in
front of/on the target. If the target is chasing and very close, it
might be more effective to drop the soap/banana rather than throw it,
but then this choice is another decision that must be quickly made to
carry out the slip (also you can mess that up and slip yourself)
> 
> A "MISS" popup is displayed mostly just to communicate that this was
not a glitch until players get used to the idea. This popup can be
removed later if we don't want it
> 
> I tested what I could think of, but might have missed something, more
eyes would be good on this one
> 
> fixes #18027
> 
> ## Why / Balance
> Slips are too easy for how annoying (or potentially lethal) they are.
Currently, slip throws are heavily slanted to succeed at short range,
where they will nearly always hit. As the range increases, it becomes
more and more possible to dodge. But it's basically impossible to _fail_
the attack, the question is, will the target be able to anticipate and
slow down to dodge it. This change is intended to make thrown slips,
especially at short range, difficult for the attacker too, not just the
target.
> 
> If the argument for the current state is that the target should git
gud, why should that not also apply to the attacker?
> 
> 
> (Also if we want to talk about what's "realistic", it also makes very
little sense to yeet a banana peel at someone and have them fall over
from that, unless one tacitly agrees that the attack automatically
always hits right under their feet (yet keeps flying anyway) )
> 
> ## Media
> 
>
https://github.com/space-wizards/space-station-14/assets/35878406/9e548b2d-ab99-4cbf-98b8-9ecd7cd14711
> 
> - [X] I have added screenshots/videos to this PR showcasing its
changes ingame, **or** this PR does not require an ingame showcase
> 
> **Changelog**
> 
> Make sure to take this Changelog template out of the comment block in
order for it to show up.
> 🆑 Errant
> - tweak: Thrown objects can no longer slip while they are still in
flight.
> 


</details>

Co-authored-by: SimpleStation14 <Unknown>

Content.Shared/Slippery/SlipperySystem.cs

@@ -1,9 +1,12 @@
 using Content.Shared.Administration.Logs;
 using Content.Shared.Database;
 using Content.Shared.Inventory;
+using Robust.Shared.Network;
+using Content.Shared.Popups;
 using Content.Shared.StatusEffect;
 using Content.Shared.StepTrigger.Systems;
 using Content.Shared.Stunnable;
+using Content.Shared.Throwing;
 using JetBrains.Annotations;
 using Robust.Shared.Audio.Systems;
 using Robust.Shared.Containers;
@@ -30,6 +33,7 @@ public override void Initialize()
         SubscribeLocalEvent<SlipperyComponent, StepTriggerAttemptEvent>(HandleAttemptCollide);
         SubscribeLocalEvent<SlipperyComponent, StepTriggeredEvent>(HandleStepTrigger);
         SubscribeLocalEvent<NoSlipComponent, SlipAttemptEvent>(OnNoSlipAttempt);
+        SubscribeLocalEvent<ThrownItemComponent, SlipCausingAttemptEvent>(OnThrownSlipAttempt);
         // as long as slip-resistant mice are never added, this should be fine (otherwise a mouse-hat will transfer it's power to the wearer).
         SubscribeLocalEvent<NoSlipComponent, InventoryRelayedEvent<SlipAttemptEvent>>((e, c, ev) => OnNoSlipAttempt(e, c, ev.Args));
     }
@@ -52,6 +56,11 @@ private static void OnNoSlipAttempt(EntityUid uid, NoSlipComponent component, Sl
         args.Cancel();
     }
 
+    private void OnThrownSlipAttempt(EntityUid uid, ThrownItemComponent comp, ref SlipCausingAttemptEvent args)
+    {
+        args.Cancelled = true;
+    }
+
     private bool CanSlip(EntityUid uid, EntityUid toSlip)
     {
         return !_container.IsEntityInContainer(uid)
@@ -68,6 +77,11 @@ private void TrySlip(EntityUid uid, SlipperyComponent component, EntityUid other
         if (attemptEv.Cancelled)
             return;
 
+        var attemptCausingEv = new SlipCausingAttemptEvent();
+        RaiseLocalEvent(uid, ref attemptCausingEv);
+        if (attemptCausingEv.Cancelled)
+            return;
+
         var ev = new SlipEvent(other);
         RaiseLocalEvent(uid, ref ev);
 
@@ -107,7 +121,13 @@ public sealed class SlipAttemptEvent : CancellableEntityEventArgs, IInventoryRel
 }
 
 /// <summary>
-///     This event is raised directed at an entity that CAUSED some other entity to slip (e.g., the banana peel).
+/// Raised on an entity that is causing the slip event (e.g, the banana peel), to determine if the slip attempt should be cancelled.
 /// </summary>
+/// <param name="Cancelled">If the slip should be cancelled</param>
+[ByRefEvent]
+public record struct SlipCausingAttemptEvent (bool Cancelled);
+
+/// Raised on an entity that CAUSED some other entity to slip (e.g., the banana peel).
+/// <param name="Slipped">The entity being slipped</param>
 [ByRefEvent]
 public readonly record struct SlipEvent(EntityUid Slipped);