Hello, I have an AI character that I want to follow a spline path, there are many spline paths in the world that the character can follow, I want to be able to detect the nearest spline path to the character and have them follow that one.
In a perfect world I would have the character detect the spline with AI Perception however I can’t find a way for that to work so I have been trying using Sphere traces, this is still not working.
Is there any way to dynamically detect splines at runtime, without using a spline mesh component?
(I don’t want to use spline meshes due to the number of splines present in the world and wanting to keep things efficient)
I’m guessing since you said there’s a ton of splines it’s probably not effective to take an array of the ones in the cell and just checking distance to them first, then LOS on the closest, then pick it’s points and do the same?
If you’re having the splines that aren’t in the AI area culled then it may not be so bad. Were you using them like patrol points? How many AI are going to be running this? If many, could it be handled more data oriented?
The trails represent smells. I am trying to give animals the ability to smell and as far as I can work out splines are the only way I can create a dynamic trail that moves and has a direction an entity can follow.
The important point is I want the search for the destination to seem more natural, I don’t want the animals to suddenly walk directly to the end point, but have to follow a trail to it.
This is why they need to detect the trails, to they can identify the smell.
The array method would also not work because I need to know the closes spline at any point along, not just the closest spline origin.
There will be a lot of animals using this system, and the trails move and change with weather conditions so I’m not sure how any data solution could replace this.
I am open to any solution with a followable, dynamic trail, with direction that doesn’t use splines, that was just the best solution I could think of (except turns out I can’t detect them)
Hmmm, well technically you could just tie overlap triggers to the spline points then poll those for the closest node.
The other way to go about it would be to recontextualize how you’re thinking about the splines. If you just need the illusion of natural movement, you could just generate a couple of semi random paths when the animal stumbles across the scent, and just have it’s AI follow the correct one a bit then a false one, then back on the correct one etc. You could even randomize it and stat it out.
@SupportiveEntity, thanks for the ideas, very helpful, will try those.
Just wondering though if there is any reason that splines are not detectable. Surely there are other a lot of times that it would be useful to have a spline detectable for dynamic interactions, so why not have them detectable.
Just a little odd.
Technically they are just like data objects at the end of the day so like other data objects they don’t really have a world footprint as they are really just location data. Usually when you want to use splines like this, you have to find a way to shrink your dataset, be it collisions, generating them on the fly, or any number of ways to make it to where you don’t need to process so much data at once. So if it’s not too intensive you can technically detect and iterate on all of them, but that’s a TON of references to look through if done the way you were going to go the path you were before.
That said, if you need help with the implementation directly we could walk through how we can take your use case and make it work!
No worries, if you have any questions about an idea you have for implementation feel free to ask! There’s many ways to go about it, but you definitely want to be efficient with it. Anything that’s constantly checking anything will be a strain, especially if many actors are doing it.
Apologies for bringing this topic back from the grave…but Im facing a similar situation here and in my scenario, Im spawning more than 1k Road splines in the world and my objective is to detect the road that is overlapping with an actor that I will be spawning at runtime, I’m unable to think of an efficient way to get the road splines overlapping with the polygon and it has to be splines. How am I supposed to detect the spline that intersecting/overlapping with the polygon.
Hey there @ARIANK0076! You mentioned thousands of road splines, are you making new actors at runtime for all of them or just the one actor you’re referencing? What’s the exact use case? It sounds like you’re working on a City Builder. Constant collision checks at that scale can be rather inefficient. There’s often a better more data oriented approach, but that answer gets wildly more complicated depending on what you need.
Hey @SupportiveEntity Thanks for replying!
I’m working on something like a city-building system where each road is represented by a separate actor, and each actor contains a single spline. Since I’m spawning more than 1000 road actors dynamically at runtime, I needed a way to detect which road overlaps with a newly spawned actor. Initially, I was trying to interact with the road splines directly, but I found a more efficient approach—By retrieving the reference to the road actor itself without having to interact with the actor. This method works perfectly for my specific case. However, I’m still curious about how to handle similar situations in a more general way.
Glad you have a working method! I would recommend testing the performance of your method before getting into full swing. If these checks can be done before a user has to interact, then you can just iterate on just checking the positions you have now. In a general sense, checking the location of the actor at the time is fine, though with splines the actor’s location isn’t always relevant. Querying spawning locations or if you have a dataset before like a point cloud, you could technically check against it as data before having the query the actors, as it would be more efficient.
Though if this leads to performance issues from the calculations, something of this scale might benefit with more of a dedicated data oriented approach. I would probably look into the methods that the City Sample was generated with, including learning about the MASS entity system if you intend to have cars driving these roads.
Links for the City Sample info and MASS entity info:
Note that MASS is still experimental for the time being, and you may have to build your own data oriented systems on top of it for what it lacks.
Appreciate the reply! will look into this. So far, the method I used is the only way I can detect actors containing spline specifically for my scenario only.