Level Design PathNode Confusion

[Dealman]

So I recently got back to playing Killing Floor 2 with a friend and we've been having quite a bit of fun. I've always been curious to get into modding KF2 since it uses UDK which I've used a little bit before.

But while I am familiar with how most of the stuff works, what has me confused is the pathfinding. For the most part the KF2 SDK has a pretty nicely decked out wikipedia which helped me get started. But unfortunately the article about navigation is really lacking and I think out-dated nowadays?

So I've got a few questions and hopefully I can get pointed in the right direction!

1. Path Options, Missing Options?

According to the navigation article, there should be a fair bit of information under the Path Options category. However, I do not get these at all. Whether a custom map or if I load for example KF-Farmhouse. Is this something that was changed - or removed entirely? Redundant perhaps?

2. How Pathfinding Works

There's not a lot of information about how pathfinding really works, all the article does is tell us how to plop down nodes. Not where or why we should do so. Like, I understand the basic concept of how it works - I've done some basic AI pathfinding in UE4.

But I want some guidelines. For example if I make a basic 'greybox' map using the modular kit to prototype, should I put one node on every tile? That seems very ineffiecent. Or do they work exactly like waypoints? What about spacing between nodes? Rotation?

3. Anchor Points

This is something that I believe isn't covered at all in either article, but nodes have to be put close to KFSpawnVolumes which makes sense, they need to know where to go when they spawn - but what are the rules here? How close should they be? Inside the volume?

4. PathNode vs KFPathNode

I believe the former is UDK's own node, but what differs between them? From my tests it seems they both work and seem to fulfill the same purpose? Is there a reason I should use one over the other?

5. Connections

In the article about navigation for doors, there are red lines connected to what I assume is the door trigger. How are these connected? Is it an automatic process when they're close enough or some keybind/property? Similar to how you connect a TraderPod to the TraderVolume?

Summary

I guess that's it. I've already done a test map and everything worked out pretty nicely except for navigation. My FPS would often take a big hit when zeds spawned, and I assume that is because I built it out of the modular kit and slapped a path node on more or less every tile(this is how I learn stuff ).

So I now want to take it a bit further and make the map a bit more advanced, more obstacles and scenery and improved pathfinding. But I'd love some tips/hints/whatever for pathfinding before I jump to the next level.

Thanks in advance!

PS. not sure if helpful, but the idea I have in mind is to make a map similar to that of Outpost 29 seen in the Starship Troopers movie and game.

 

[Seanchaoz]

Welcome back to mapping! Careful though, it gets addictive real quick

1. There really aren't a lot of options for pathnodes. And some of the ones there are, aren't really used or needed. The most common options used by the level designer are Proscribed and Froced paths. In some rare occasions you may find a use for One Way Path, but personally I have never used any other setting than the 2 former. Maybe when we get more core game modes, like Objective, we will see more usage of other path node settings.

2. You do not need to put a node on each floor mesh, that's complete overkill and will only needlessly complicate navmesh calculations, degrading your map performance. As long as your nodes connect to each other, you should be fine. Depending on world gemoetry though, you may in certain areas wish to add extra nodes in close proximity to smoothen out AI movement around corners or tight spots. In large open areas, you can essentially place nodes at max distance from each other, but keep in mind that the lines between each node dictates the route zeds will move along if they are not in close visual proximity to a player. Rotation on path nodes is completely irrelevant as far as I know. It does however matter on Player start nodes, customization points and boss spawn volumes.

3. Actual numbers are a mystery to most (if not all) of us I believe, but general rule of thumb; On small volumes (the 320x320 UU ones) you are safe by smacking a single node right in the center, although it usually also works having nodes at the edges or even slightly outside the volume. On the large volumes (640x640 I believe) you should aim for at least 2 nodes inside the volume, spaced out by roughly 320 UU of each other. A single center node may be enough but I personally wouldn't risk it.

4. Again, I'm not sure any of us mortals know what the difference is, so my reasoning is that if TWI went through the trouble of making a special KF2 exclusive node, you should probably be using that

5. Door nodes will automatically connect to all nearby path nodes during map build. The red lines you are seeing are manually Proscribed paths, because doors are very wonky in how they function, and work best if they are connected to only a single close-by node on eeach side of the door, with ALL other surrounding nodes being ignored (proscribed). This will give the AI the most favorable behavior when interacting with a door. The more nodes the door trigger is connected to outside of the closest one on each side, the more likely the Zeds are to act strangely and get confused when trying to enter/open/bash on a door.