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by Sebb767 1802 days ago
> If a user can see through a wall locally how can ‘distrusting’ anything fix that?

The fact that the client can remove the wall and see something behind it is due to the fact that the client is trusted to do the hiding. An untrusted client would not receive the enemy position until the enemy is visible. This, however, comes with the drawback that the server needs to do the culling - That's why pretty much nobody does it right now.

Aimhacks would still be possible, of course, but client-side anti-cheat can't prevent those either.

2 comments

Valorant specifically actually does this to a degree, and there was a quick article written by one of their anti-cheat developers that roughly explains their approach.

https://technology.riotgames.com/news/demolishing-wallhacks-...

Right it’s not a realistic suggestion as not even the client does it in software!
Why do you think that? The server needs to at the very least trace a line for a shot. There is nothing difficult or slow about that. Before you say that it is done with a z-buffer or something similar, think about third person camera angles or how older games did the same thing. You might want to pull back on being so certain if you don't have experience with game engines or graphics.
> Why do you think that? The server needs to at the very least trace a line for a shot. There is nothing difficult or slow about that. Before you say that it is done with a z-buffer or something similar, think about third person camera angles or how older games did the same thing. You might want to pull back on being so certain if you don't have experience with game engines or graphics.

But... it is done with a z-buffer.

If an opponent is obscured behind a nearby pillar or something, that's not going to be culled in software - that's done by the hardware z-buffer as part of the render process.

You can see this for yourself if you look at a game being run with wireframe rendering. You'll see it's in the same render node so it's still rendered - it's just obscured by closer geometry. And it's how some cheats actually work - they basically turn the wireframe back on!

'Tracing a shot' is casting one single ray.

For example read this article someone else linked https://technology.riotgames.com/news/demolishing-wallhacks-... and look at the last animation.

You are conflating needing information about player position with visibility of individual polygons.

Also you are forgetting that you just said that line of sight was done in hardware and you didn't explain how that would work for a server testing if shots actually hit.

> You can see this for yourself if you look at a game being run with wireframe rendering. You'll see it's in the same render node so it's still rendered

What does this even mean? What is "it" here and what is a "render node" ? There are hierarchies of transforms and players are going to be separate from the environment. This doesn't actually mean anything.

> it's just obscured by closer geometry. And it's how some cheats actually work - they basically turn the wireframe back on!

Yes, you are restating the context of what people are talking about, not what is actually being talked about, which is the timing of when the server should send visibility information, which is what your link is actually about.

Your link is actually directly contradicts what you are saying since it uses both an expanded bounding box based motion extrapolation and precomputed visibility, neither of which has anything to do with a z-buffer.

Look at the last illustration in that article.

Can you see how the red outline of the opponent appears while they're obscured behind the pillar?

When that red outline appears it's showing that the opponent is now being rendered, and that the z-buffer is being used to obscure them from behind the pillar.

This discussion is about how to make the red outline not appear until the opponent is actually visible.

The article goes into lots of ways to make the red outline appear later, but it still appears before the opponent is actually visible on screen.

That's the issue that people want to solve.

Consider an example of an opponent with just one pixel of their gun visible around a corner. How do you send that information to the client without telling them there's an opponent there, so that the user has to actually see the pixel? You'd have to just send that one pixel, right? Now we're talking about rendering server-side!

" When that red outline appears it's showing that the opponent is now being rendered, and that the z-buffer is being used to obscure them from behind the pillar."

Yeah, that's game rendering in the engine. That's visualizing something, not illustrating how the server is doing it. Did you actually read and understand your own link?

"That's the issue that people want to solve."

No it isn't, you misunderstood your own link to the point that you have it backwards.

The server not rendering the entire game from each person's perspective every for every player every frame.

The problem is being able to see every player walking around all the time.

Think for a moment what would happen if the server actually had perfect visibility - by the time you can see them it is already too late. You should be able to see them and then the server starts sending you a position. By the time you know you should see them, you should have already seen them and the other player pops into frame.

That isn't even buried in your own link, it's at the very top.

"Consider an example of an opponent with just one pixel of their gun visible around a corner. How do you send that information to the client without telling them there's an opponent there, so that the user has to actually see the pixel? You'd have to just send that one pixel, right? Now we're talking about rendering server-side!"

This is gibberish and is a lot like Frank Abignail trying to BS pilots. Once again your own link explains why this is nonsense from a lot of different angles, did you even read what you linked or did you just look at the pictures? It explains everything clearly.