"I'd like to get zBlock 4.4 out by the end of the week"

What is the next zBlock update about?

Mike 'J3Di': From the next zBlock update you can expect much of the same: We are continually attempting to prevent exploits in the Source Engine. Though this next update will focus heavily on Counter-Strike: Source and correcting exploits which are affecting many competitions both online and LANs. In particular you can look forward to the fix for the crouchbug and a feature which will prevent players from exploiting bunnyhopping.

Do you use the crouchbug and the bunnyhop as well?

J3Di: I don't use the crouchbug personally though of course I well tested it on some public servers. Bunnyhopping I can perform rather well and it's something again I only use on public servers which can be fun when you get to a position faster than a player thinks possible and you get the cheating accusations. But generally I don't bunnyhop much as it has always been illegal in the leagues I play.

What is the current status of the next version?

J3Di: Currently the crouchbug fix and bunnyhopping work is completed - they are fully tested by a large group of testers and found to work more than satisfactory. To quote Loic 'RegnaM' Péron from Team VeryGames on the bunnyhopping fix: "This is ridiculous! I've just discovered a new game, actually, it feels different. Why? Simply because it's perfectly fixed."

I've also just completed working on a fix for super-boosting, where a player can be propelled to enormous heights by jumping off another player or collision with an object that is now being tested and will be released along with the 4.4 update. It's shaping up to be a large one.

How do those fixes work ingame?

J3Di In both cases it's the best to understand the problem before I explain how the fixes were implemented in the plug-in. There is a general misconception on how both problems occur.

The problem with the crouchbug is that the server only has two states for a crouching player: standing and crouching. Therefore the server is not aware of the player moving from a fully crouched position until they are fully standing. The fix is to not allow ducking movement unless the player is fully standing. Clearly this action causes a client/server view mismatch: With prediction on the client believes it can duck as often as it likes, but the server is saying otherwise. Typically this causes no problems at all. If the user is crouchbugging then they will notice a tiny glitch (like lag) in their view as a predication error is fixed from the correct server view. The server won't let the player crouch until he is fully standing. The feedback we've received from the glitching shown whilst crouchbugging is that it is generally fine, but looks a bit odd the first time you attempt to crouchbug. It will be certainly amusing to see someone crouchbugging in a match if they don't realise the new zBlock is installed just to have their heads shot off (laughs).

The problem about the bunnyhopping is that there is a coding over-sight in the Source Engine. When a player jumps they have an additional velocity applied to their movement, the same when a player strafes. Repeated strafe jumping allows a player to gather a huge amount of momentum. Now with our fix this looks different: As the player jumps the second time whilst performing a bunnyhop their velocity on the horizontal becomes clamped to their maximum client speed.

Why did it take so long to fix it? People are waiting for it for quite some time now.

J3Di: I've been incredibly busy in life lately, this is a relatively simple software project for me. We have a priority system in place which led to these items being fixed later. Researching the Source Engine can be tedious at times, a lot of time is spent analysing a problem and where it stems from before a solution can be made. I'm not a stranger to a dissassembler so this wasn't much of a problem. Other than an odd typo confusing my beta testers. For example I wrote "bunnyhopping enabled", when it should be disabled and got a load of feedback saying it didn't work.

When do you want to release it?

J3Di: I'm not sure yet, it depends how things go because I'm a busy guy. I'd like to release 4.4 as soon as possible but it mostly comes down to the website and testing. The weekend is the deadline! There is drinking to be done (laughs).

That sounds like serious business.

J3Di: Well, I've got a lot of personal stuff to do. zBlock wise there are currently two plug-in’s being developed side-by-side as I decided to go back and restructure a lot of old code to make it more maintainable. This will eventually make my work on zBlock much easier.

With the new fixes you've done something Valve wasn't able to in the last couple of years. Congratulations.

J3Di: I'm sure Valve already know the solution, they have a very competent bunch of programmers. Unfortunately they are a business and so they are limited on resources, however we have the motivation and ability to say yes - today we'll fix that whereas their teams must work on other projects.

Where do you take your motivation from to do all this?

J3Di: When I started my work on zBlock I only had a few months experience writing C++ and lots of experience in other languages, Java for example. I found it useful to practice and build on my programming skills. Knowing that I have the talents to give something back to the community and combat exploiters - which were at an epidemic level at that time, worse than swine flu (laughs) - was a major motivating factor for me.

Not only the community and the game but also the team behind zBlock has changed. How does it look "behind the scenes" nowadays?

J3Di: Currently there are only three people who actively work on zBlock. There is myself, I am the programmer and do all the research into how Valve code works when required. We also have two support gurus, CodeRed and Orion. TheUnknownFactor can be occasionally seen but is inactive, and we like to honour our previous members - so I'll mention Trepje who was the previous coder for zBlock version 1.

When a new bug occurs it either lands in the hands of one of our support guys since they really do know what people are up to in the community at an uncanny level or it comes to us on our forums that are sadly offline at the moment. We test the problem or exploit and see if we can replicate it or better understand it in-game. If it's not clearly understood it comes to me to do the reasearch. Otherwise I just get instructions on how to fix it and go the keyboard.

How has been your relation to Valve during the time?

J3Di: During my time on zBlock I've had many e-mail conversations with people at Valve, someone from the zBlock team will always contact them with our knowledge. Typically this role used to go to TheUnknownFactor, but now we all discuss things with them.

In the past they have made updates which have provided better means for us to receive essential bits of game information using a plug-in. For example when Valve prevented server plug-in’s from sending commands to be executed on the game client, we were some of the first to get that code which enabled us to go and work on the plug-in. Essentially they broke zBlock in an update and then spent some time getting it working again using a new method.

That truly shows the importance of zBlock.

J3Di: Yes. Game-monitor.com currently shows over 15,000 servers running zBlock. That's a huge amount of users each day, also the bandwidth reports from our website are quite "fun" (laughs). When I see it being used in professional LAN tournaments that also brings a certain satisfaction and I know we are doing something right.

What other things do you want to fix in the future? The silentrun and the defusebug are just two bugs that pop into my mind right now.

J3Di: The defusebug is something which is on the radar so to speak, it's relatively low priority however as players know they must shoot items off the bomb. Silentrun I'm not aware of - isn't that a CS 1.6 bug?

You can also walk very silently in CS:S but you need another technique[...]

J3Di: testing

J3Di: It seems that the silentrun is an issue but I can't make it entirely silent, it will be looked at. I don't think I'll have time to get around for the 4.4 update though. I'd like to get that out by the end of the week for the the-eXperience LAN. Also I'd like it available for auto-update which depends on the state of our website.

Thanks for the interview. You have the last few words.

J3Di: Shout-outs to the zBlock team: CodeRed, Orion, TheUnknownFactor and Trepje. Thanks to our beta-testing team and everyone who reports exploits to us, more shout-outs to the admins of EnemyDown.co.uk.