I'm creating a 2D RPG engine (like alot of others it seems). Right now I'm working on a way on how to calculate gaining experiance, leveling up, damage done by XXX and things of that nature. I've searched arround and can't seem to find anything useful related on this subject. So how do you guys come up with your algorithms? or maybe a few examples of some to get me started would be nice. Thanks, Sean Chapel

You have to make a set of rules for yourself. For example, some computer roleplaying games use the (Advanced) Dungeons & Dragons ruleset (from the pen and paper game). Some games just make up their own.

Here's one ruleset for you to look at, if you wish: D20

You should take some time when creating your own ruleset.. It can be quite tricky to balance it properly.

And because I'm such a nice person I uploaded the ruleset script file for my game just for you to take a look at. The full source for the can be found at sourceforge.

EDIT: Note that I don't find my rules particulary good but they were meant as an example of how things could be done.

Doh! how could I over look DnD so easily. Thanks much for the help.

I recomend staying away from the DnD system, the system has a lot of limitantion that were casued by trying to simplify the math, but computers can crunch numbers faster than DnD players and you should take advantage of that

in a perfect world you'd keep the game rules separate from the engine itself. most likely scripting of some sort would be able to handle the game rules details.

also, the license for d20 sucks (although i am still unclear if you can use it if you don't call it d20).

krez,

What you said is interesting. I went to the link and I also interpret the license as saying you can use it as long as you don't mention D20 or Dungeons & Dragons anywhere.

I emailed Wizards of the Coast and asked them straight out. I will post the reply here (if I get one from them that is).

Marcus

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Original post by MarcusLM krez, What you said is interesting. I went to the link and I also interpret the license as saying you can use it as long as you don't mention D20 or Dungeons & Dragons anywhere. I emailed Wizards of the Coast and asked them straight out. I will post the reply here (if I get one from them that is). Marcus

That's what it looks like. From the Software FAQ:


Q: So I could make a game?

A: Sure. Remember though, you cannot use any Product Identity with the OGL or claim compatibility with anything. So you can't say your game is a d20 System game or uses D&D rules or call it "Elminster's Undermountain Crawl".

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Original post by Seoushi I'm creating a 2D RPG engine (like alot of others it seems). Right now I'm working on a way on how to calculate gaining experiance, leveling up, damage done by XXX and things of that nature. I've searched arround and can't seem to find anything useful related on this subject. So how do you guys come up with your algorithms? or maybe a few examples of some to get me started would be nice. Thanks, Sean Chapel

One of the best things to do in the design stages for something like this is get rough numbers, make the game and gameplay as you want it, then tweak the numbers. Making finite numbers from the beginning can sometimes cause in-game balance problems.

Base your pre-tweak numbers on these things:
How long do you want each level to take? How much of a modification should their experience-reward get if they kill something X levels higher or lower than them?

As for the damage, this is where it gets tricky. The only thing I'd suggest is throw some numbers in, then have friends test it and have the program automatically log their actions. After a week or two, get the logs from all (or most) of them and look through them (with a log parser, of course). If you find a large gap [If over 100 testers, 5% would qualify as large in my books] between the most often used weapon/class/spell and the second most often used, the most often used thing is likely overpowered. The same applies to the bottom of the graph and underpowered weapons/classes/spells/abilities.

Thanks for the new replies. I was thinking this over some and I still haven't really come up with any algorithms yet. Reason being is I still haven't even gotten to the part where I need to use these algorithms (still working on the map engine right now). Anyways this is gonna be in the back of my head till I actaully need these things. While a DnD based system is cool I think it might add a depth to my RPG that I don't want (an abundnace of customization is much harder to program). I was talking to a friend and he pointed out that gamefaq and simular sites have enemy mechanic type faqs and I found something that helped tremendously. Example ( http://db.gamefaqs.com/console/psx/file/final_fantasy_vii_enemy_mech.txt ). So if you have any cool/different ideas on what to base it on or something like that then please feel free to post them.