Ok. Now to try and continue the attempt to limit version miss matching and to help people out who wish to create custom perks or server admins who want to work custom weapons into their perks.

Note: This first post may look like a lot, but it's less than an afternoon's reading.

Part One : Prerequisites

Primers

Forum member Benjamin created some very useful tutorials. I suggest you read the first one at least as it covers the actual set up and compiling of mods/muts/packages.

Creating a Basic Mutator
Mutator Essentials
Multiplayer Mutators
Modifying Existing Weapons

CPlusPlus & UnrealScript

Unreal Script is an object based programming language derived from C++. I'm not going to teach you about C++, I'm no where near qualified (or patient) enough to do so.

http://www.cplusplus.com has all the info you need on C++ including tutorials. Take note of how object based programming works including inheritance and projected properties. In here are all the operators and statements you'll need for the maths and checks.

UnrealScriptReference Has pretty much all the info you need on the unreal script functions and more. You can also use http://wiki.beyondunreal.com/ as a resource.

This should be enough to get you started by the time you've had a skim over and maybe tried some of Benjamin's tutorials I'll have written up the next section of the tutorial.

Note: To the experienced programmers; Marco, ScaryGhost, Benjamin etc. If you spot any mistakes or omissions please do send me a message and I'll correct any mistakes I've made. Also feel free to send any suggestions.


Tutorial One – Setting Up & Testing

So now that we have covered some basics of C++/UnrealScript and compiling we need to set ourselves up to build our new perks. There are other ways of doing this but this is the way I prefer to do things.

First download and install ServerPerks from this thread. -Be sure to thank Marco while you are there. ;)

First create your mod folder; “WhiskyPerks” for this example and within that a folder called “classes”


Next navigate to .../KillingFloor/System and open the killingfloor.ini
In the EditPackages lines I add after ‘KFMutators’ the packages for ServerPerks and then your own.


Now going back to our mod folder we set up I’m going to create a simple perk extension that I will use for following tutorials. This is saved as a .uc file in the classes folder. Don't forget the file name has to be the same as the class name.



This is all the code I’m going to use for the time being. What I’m doing here is extending off of the SRVetCommando which is the commando class that comes with ServerPerks. This will inherit all the functions and properties of its parent class with the exception of the Perk’s name, now “Whisky Commando” which overrides the parent class property.

Compile and if you’ve been following along you should have no problems. Next navigate to .../KillingFloor/System and open the ServerPerks.ini file (you can do this in game as well from the mutator window I just prefer doing it here) and add your new perk to the Perks= lines, in this case Perks=WhiskyPerks.WVetCommando.


Run the game and test. (Don’t forget to turn on ServerPerks from the mutator menu!)


And there we have it, our very own ‘custom’ perk in game. Admittedly this is only a name change but it is a start. Next tutorial will show you how to start customising bonuses and discounts.

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Tutorial Two : Extending and Overriding Perks

We will start simply to begin with. Now you can find ALL the functions you need in other files, both in the original perks in the KFMod folder in your .../killingfloor/ directory and in Marco’s ServerPerksV5 source files which are still available on his thread.

Returning to our new Commando class, there is a gun that he’s always enjoyed but finds very expensive. So let’s give him a discount on a weapon.

Now there are two ways we can do this, we can either extend the function or overwrite the function.

Extending a Function

I’m going to opt to extend the function to start with because it’s less coding and I don't need to do it from scratch. Our weapon shall be the G36C by Flux.

First download the mod and install it. You’ll need the files to be able to compile the perk.

This is what we are going to add to our perk to give it a discount for the weapon.

Code:


Let us break it down:

Code:

This line loads the package we need.

Code:

Comment so we know what we are doing here.

Code:

Calling the function to scale the cost of the weapon.

Code:

IF statement, if the gun is a G36C then perform this process.

Code:

Easy bit of maths to create the discount. With comment so you can see at a glance what is going on.

Code:

Return value to the super class which means it returns this value to its parent class so that both work together rather than this function overwriting that of its parent.

Compile and test by adding the weapon to the store and switching between perks to see the effect on the discount.

Overriding a Function

Overriding is ideal if you want replace a function completely, for example removing all damage bonues; like so.

Code:

This simply overrides the parent function so our new commando doesn't have his damage boosts and we have still not touched the base ServerPerk package.

Perk as it stands now:

Code:

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Tutorial Three : Perk From Scratch with Custom Stats

“But Whisky, Gartley or whatever you call yourself” I hear you cry “I don’t want to edit existing perks I want to make my own big shiny new perk!”

Well ok let us start to make our own perk then. Firstly we are going to start by setting up the requirements; scary ghost was kind enough to start this one off. So I’m going to use his as a base and work from there. I’ll also be turning the new commando perk into a standalone perk.

#1: First we need a new damage type. Have the AwardDamage function use the ProgressCustomValue function. You'll want to derive your custom damage type from KFWeaponDamageType.

Code:

#2: Create your custom requirement and name it something sensible.

Code:


#3a: In your custom perk class, bind your custom requirement to the perk.

Code:


#3b: In this example I also use this stage to replace the G36C’s DamType with the new calss. If you are creating a custom weapon you can use the above DamType in the weapons fire class.

Code:


#4: In the perk create your custom perk progression.

Code:


#5: Add in all the extra bonuses and features you want.

#6: Set up the default properties including perk descriptions. If you wish the custom info to display past perk 6 you need to know your maths and string replacements.

Code:


Remember to add the texture using the obj load function



Special thanks to Scary for pre-empting this one. His original post (link below) helped me to put this last one together.






The final perk:

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Not to be a dib, but would it be possible for you to do a video style tutorial? I only ask because I am by far a more visual learner. All I need is to be able to see it done once and do it myself and I usually get it one the first go around. Following written instructions, however, is a different story. Also if you could put up a step by step making of a gun in video form I would love it. Thanks

Cheers Whisky, comes in very handy as its a hands on tutorial!

Glad you find it useful.

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Heya Whisky, hoping you can help me out with an array error in requirements.

my perk is to be reliant on other perks, ie to use this perk you need to have unlocked the level requirements for each other perk first.

IE, to use level 0 of this new perk, you will need to have unlocked level 1 of Sharp, Support, etc etc.

My perks go from 0 to 15 levels

All other custom stats are bound in those perks.

the new custom stat (to denote a member, since i havent worked out a different way yet, i know flux has something implemented)

Anyways, I'm currently getting an Out of bounds array error

Error: SykPerks.SYKSykosis: Out of bound array default property (6/6)
Error: SykPerks.SYKSykosis: Out of bound array default property (7/6)
Error: SykPerks.SYKSykosis: Out of bound array default property (8/6)
Error: SykPerks.SYKSykosis: Out of bound array default property (9/6)

What you are trying to do would be better implemented before the perk level. Flux uses his own version of ServerPerks that allows him to flag a member as having donated or is a VIP and that allows the perk to be selected. tbh he'd be best to ask about that side of implementation.

Marco did show an example of this in work with what he called ServerPerksX (Now redundant as he has implemented the feature into an update.) He did this by extending off of server perks. imo better then building your own version of serverperks. As it's easier to maintain.

http://forums.tripwireinteractive.com ... p?p=1069437&postcount=704

Let me know if that helps you out.

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Cheers heaps,

I remembered seeing something like that a while back, couldn't find it again when i was searching for though.

I havent looked into the servperksx yet, but i did do some testing with the arrays, I think there is a limit of 6 requirements for a perk (limited the amount of requirements when using arrays and when not, both hit a 6 requirements before erroring), i haven't started digging around yet, but i'll probably make different requirements rather than having to accomplish all other perks requirements to gain a level in this perk.