Trouble with agent / trouble with generating correct navmesh

[Samsy]

Screen.Recording.2024-03-01.at.15.40.29.mov

Hey hello there,
Thanks again for the work done, it's really impressive

I've got a bit of trouble understanding the agents : see video

Sometimes they are not able to find a path, and they just hit continuously the wall, but also sometimes, they fail to go through a tile, like if a tile limit is preventing them to go through.

This is my updateAgentPositions, I'm passing the target position ( the player position ) and the delta

   updateAgentPositions(target, dt ){

        this.crowd.timeStep = dt

        this.crowd.update(dt)

        let i = 0

        const targetPosition = this.navMeshQuery.getClosestPoint(target)

        while(i < this.agents.length ){

            const agent = this.agents[i]

            agent.goto(targetPosition);

            const agentPosition = agent.position();

            agent.model3D.position.set(agentPosition.x, agentPosition.y, agentPosition.z)

            i++
        }
    }

Also, this is how I'm creating those agents :

createAgent( position = {x: 0, y: 0, z: 0}, radius = 2){

        this.navMeshQuery.getClosestPoint(position);

        /* get a random point around the given position */
        const initialAgentPosition = this.navMeshQuery.getRandomPointAround(position, radius)
    
        const speed = (Math.random() * 10 + 10);
        const agent = this.crowd.addAgent(initialAgentPosition, {
            radius: radius,
            height: radius,
            maxAcceleration: speed * 10,
            maxSpeed: speed,
            collisionQueryRange: 0.5,
            pathOptimizationRange: 0,
            separationWeight: 1.0
          });
        
        agent.model3D = new Mesh(new SphereGeometry(radius,10, 10), new MeshBasicMaterial({ color: Math.random()* 0xffffff, wireframe: true }))

        this.agents.push( agent )

        return agent

    }

I've been following all the presets, moved things around, but never can find a good path finder solution yet

Also, another question, I'm very often getting those geometry discrepancies on the generated mesh, I don't know if anyone ever bumped into this yet

Edit: I did fix the discrepancies a bit by lowering the edge length to the minimum, but I think this is also related to :

#156

[isaac-mason]

Hey @Samsy, if you're comfortable doing so, could you share the model you're using and the code you're generating the navmesh with? Happy to take a look 🙂

Some others have reported similar issues with tiled navmeshes in particular. From the visuals I take it you're using a tiled navmesh?

It's often the case that the issue is actually an issue with the recast/detour c++ libraries themselves. That said - I think it's always good to start here and make sure the javascript bindings aren't the issue before creating noise for the library maintainers.

[isaac-mason]

Thanks! I will make some time to take a look soon.

[Samsy]

Hey hello @isaac-mason :)
Bumping into this again, is there something I can do to help exploring the issue ?

Thanks a lot

[isaac-mason]

Sorry @Samsy, I haven't had time to look into this. I would start by exploring google discussions and github issues/discussions for the upstream recast/detour libraries to see if there is common wisdom for dealing with these issues.

[Samsy]

Hey hello @isaac-mason
Maybe I'm wrong, but I did look at the issues on the github and google discussions you linked, but had no chance at finding any similar ones

Can it be related to the pruning ?

[isaac-mason]

Hi Samsy,

I'm not certain whether flood fill pruning would fix this issue, I haven't had time to closely look at your model, apologies. Some related discussion on this if you haven't seen it already: #151 (reply in thread)

@rob-myers left a good suggestion to avoid calling agent.goto every frame. That would be a good first thing to try.

Echoing their comment, if you share a codesandbox / GitHub repo myself or someone else can take a look too 🙂

[rob-myers]

Hey @Samsy , it looks like updateAgentPositions(target, dt ) is being invoked every frame e.g. because you're running this.crowd.update(dt).

If so, you're also invoking agent.goto(targetPosition) every frame too. Under the hood it is calling requestMoveTarget.

I would only invoke this when the target changes. It might help.

If not, could you provide a repro e.g. by exposing a branch on codesandbox?