Best Method for Conversations with NPCs

#1 Choosing from prewritten statements always kind of sucks but there is no easy alternative..
I think the style you choose depends on the style of yur game. If NPC and player character can be quite similar and blur the line between who is real and who isn't then you should have an interface that resembles yur typical player chat interface as much as possible. But if NPCs are all like Mr.Bakery Man you buy bread from and Mrs.Gatekeeper you have to answer a riddle for.. well then ease of use would be the best way to go. Ultimately in the end streamlining the interface is most important as chatting with NPCs can get annoying and repetive. Simple easy and obvious "point and click" would certainly achieve that effect.

#2 I'm going to have to agree that it's better for the player to click on a reply in a list than allowing them to type in whatever they want.

The problem with typing in whatever they want is that you can't possibly write a program that could deal reasonably with everything they'd say. If you CAN do this, then you should go get a PHD. If you look up "chatbots" or "chatterbots" on google, you'll see that people can't even mimic a human conversation effectively when they are NOT making a game too.

#3 @Steve there's a HUGE difference between a chatterbot and your typical NPC in an RPG.

With NPCs you can put enough of a NLP in there to make sure they convered he keywords your NPC is looking for and ignore the rest. I've never seen a game that used multiple choice lists well, it's usually really easy to tell what you SHOULD choose from the list.

In all honesty, every NPC "conversation" methode has it's own (often huge) flaws. It's just a matter of picking which flaws you can deal with and trying to minimize there impact.

#4 The problem I've always had with "click the reply" type interfaces is that it is too easy for the player to figure out secrets. Just click on every link and you hear everything the NPC has to say.

A simple parser isn't really that difficult to write and all you need to scan for are keywords, but that gives you the ability to make difficult quests where the NPC may drop a hint in a 4 line paragraph of text and it's up to the player to figure it out. Those kind of games are always more fun to me than just clicking on every text reply.

#5 Runescape (www.runescape.com) does the multiple choice for not only NPCs but for broader skill use as well (if you want to check it out there's a free version :).

There are a few other ideas I will be presenting in the future, but for right now I believe the multiple choice can be worked out the best. On the contrary to Rodney's post, I believe that the choice option actually can be enhanced by different things, including the ability to ask keywords as an option. But in the long run, players will better appreciate the ease of use that lets them get on with the game instead of struggling to find the perfect keyword or paraphrase (especially with those who kant spel :)

Like J. stated, it depends on what kind of flaws you can handle with limited NPC brains! :)

- Christopher Dapo ~ Ronixus

#6 Eh. Text box spell checker included? :P

#7 I agree with J. Donavan Stanley with the fact that each conversation type has it's own flaws that need to be minimized.

Right now, I'm looking at using a few different methods, depending on the complexity of the NPC involved. For most situations, the text dialogs with statement choices would serve fine, if indeed no "secrets" were needed to be found by the player. As the missions get more complex and more subtle, I think the answer lies in the more conversive but less obvious chat interface with the NPC. It would really seem to depend on your situation, and both methods can be implemented to accomplish the goal for certain situations.

#8 Have you looked over Beffys speech resource? Although the basic example is setup in the boring 'choose a response' style, he's included hooks, comments, and even partially complete functions to do much more.
I once wrote a dialog engine for MUDs, that was based on the eliza code, but tailored for a game. Speech wasn't required, mobs could act and interact with emotions and actions instead.
I am pretty confident I can rework this a bit, and merge it with Beffys code, in which case we would have the best of most systems.

#9 Read this...it explains the different approaches quite well:

http://www.gamedev.net/reference/articles/article247.asp


Enjoy,

-Nick

#10 Nick, thanks for the resource!! =)

#11 I am a fan of clicking on pre-made options for text.

However, yes, the potential for exploiting it via just running through the options 'til you find the "right" one exists...

Have you considered this idea?

It would be hard to code, but make a system whereby if you've "asked" an NPC something already, it'll just respond, "are you deaf or something, I just answered that!" or some such, until a certain amount of time has passed.

It might add some character to the NPCs, and make the game a bit more challenging.

#12 @Alexander: That's something of a "memory" system. The NPC records the kind of questions you ask, usually because you can go back and ask again and get a different answer after completing another part of a quest. The side effect is that you can pull things like that off. Of course, it takes up a lot of space and is probably better done in single player RPG's unless you find ways of trimming down on the data used, or a more efficient way of getting it. 100GB of space doesn't cost what it used to, but it's still a huge db to be sorting through...