NPCs Doing Their Own Thing

April 20, 2018

In earlier games in the Sleuthhounds series the non-player characters have been quite limited in what they do from a technical standpoint. For the most part they just stand in a single spot in a single room waiting for the player to come along and interact with them. Occasionally the NPCs perform background animations while waiting for the player. And if they’re really lucky they may even be able to walk from one point to another within the same room. For the sizes of the earlier games, consisting of only a handful of rooms, those abilities were enough. Sleuthhounds: Cruise is set to change all that.

The cruise ship on which the next Sleuthhounds game occurs is a big place. Bigger than all of the previous Sleuthhounds games combined. It also takes place over several days of story. I didn’t want the NPCs to be confined to individual rooms for that duration. In fact, the story requires that they move around the ship so that their cabins are left empty at various points to allow the player to sneak in and investigate. As well, early on in the game I wanted to keep the number of locations the player can visit fairly limited. To help with this I wanted to have NPCs moving through the environment to guide the player.

Last time I wrote about improving the game tech to allow Ampson and Homes to be together or separate. Based on that same work but with a few more minor extensions I’ve set up the game world such that NPCs can walk from one room to another, assuming of course that they have the necessary walking animations. That made it easy to put the guiding NPCs in that I wanted early on. Having the NPCs not be rooted to the spot all the time also gives a little more life to Cruise than previous games have had.

The other key thing I’ve implemented – or improved upon, actually – for NPCs is their ability to talk to one another while the player is free to do other things. I first implemented something like this in The Halloween Deception where a bunch of background characters were seen to be talking in the background although they didn’t actually say anything. It was just for appearance in that game that the background characters could move their mouths while the player interacted with the more prominent NPCs.

For Cruise I’ve now implemented a system that properly allows two or more NPCs to talk to one another and for the player to listen to and interrupt those conversations. I haven’t used that ability much so far but I have a few ideas for some interesting sequences that could be done with it. For example, it provides the opportunity to have the player overhear conversations that they might not otherwise be privy to. And again, it helps to give the NPCs a little more life of their own rather than have them be locked off game hotspots that do nothing until the player interacts with them.

NPCs can be useful for adding life into a game. The previous Sleuthhounds games haven’t been big enough to require characters that can wander around and hold conversations with one another. Cruise provides the scope to do just that. It’s one of the ways that the new game is more ambitious than the previous ones beyond “just” being bigger.