Question Raycasting onto a navmesh game object

Hello fellow Marsians,

I want to put a 2D game on top of an image marker and am trying to get a raycast onto my navmesh with this simple code from SingleSaplingGames:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEngine.AI;
5.  
6. public class PlayerMovement : MonoBehaviour
7. {
8.     NavMeshAgent agent;
9.     // Start is called before the first frame update
10.     void Start()
11.     {
12.         agent = GetComponent<NavMeshAgent> ();
13.     }
14.  
15.     // Update is called once per frame
16.     void Update()
17.     {
18.         if(Input.GetMouseButtonDown (0))
19.         {
20.             RaycastHit hit;
21.             Ray ray = Camera.main.ScreenPointToRay (Input.mousePosition);
22.             if(Physics.Raycast(ray, out hit, Mathf.Infinity))
23.             {
24.                 agent.SetDestination(hit.point);
25.             }
26.  
27.         }
28.     }
29. }

Unfortunatly it doesn't work.

I know MARS usually looks for planes, but in my case I don't want MARS to detect any planes, just an image marker and then the game object (navmesh) I spawn on that marker.

Any suggestion. Thank's a bunch.

 

@jmunozarUTech Thank you for your reply.

I've set the image marker up like you mentioned, but I have two issues:

1. Testing in Simulation View does no longer work for some reason. I've set up a synthetic image marker. But my content only displays when I'm NOT in simulation mode. As soon as I press play the content disappears. I suspect it might have something to do with the world scale, because it worked before I adjusted it. When i build the App, the content displays like it should.

Would a "normal" raycast even work in the MARS Simulation?



2. My player Cube keeps disappearing when I test the scene on device, regardless if I render the ground or not. I suspect it has something to do with the NavMeshAgent Component, since the blue Cube appears like it should. (see image below) Do you have any ideas on how to fix this?

 

Hello @jmunozarUTech,

1. Problem 1 seems solved! I moved into the synthetic image marker in simulation view and then the content showed up and also stayed there after I moved back.

2. Is there a way to simulate my touch input in Simulation View? In other words: Could I test the movement of my playerCube by clicking on the groundPlane in Simulation View?

3. Is Play Mode possible with MARS? And if yes, how do I set it up in sync with the Simulation View?

4. Problem 2: I visualized the Collider in Simulation View (see image below) and it seems fine. Also the player cube is displayed which is also fine. But on device the playerCube disappears.



5. I tested the agents in a seperate scene without a MARS Session and they work fine.

6. I don't know how to write the code to log the agents activities. So I would need some time to look into that.

 

Hello @jmunozarUTech Exciting news! I found out what is causing the problems.

As shown in this picture below the problem seems to be that the navmesh is not transforming along with the cube, but stays at the original position it was backed in.

The red playercube is placed correctly on the navmesh, but I didn't see it because it was on the floor.

Raycasting also seems to work as the red line indicates.



I will now try to match the transform of the synthetic image marker with the transform of the image marker in the scene view. Then the navmesh should be in the right position and everything should work.

However this is not a longterm fix. Ultimately I need the NavMesh to transform with the groundplane, since I can't control the transform of the real image marker once the scene is build to device. Any suggestions?

Thanks for the replies. Huge help!

 

@unity_andrewm No I have not, since I don't think it's the right navmesh for me. I need a navmesh that is parented to the game object I want to display on the marker, since there is always some movement and recalculation of the displayed game object once it is placed on the marker. That is ok, as long as the navmesh and all other game objects move in unison and the relation towards them stays the same.

I have experimented with the A* Pathfinding Plugin and implemented a node-based pathfinding which works great for me, since it is very accurate at a very small scale (Poster Size 50cm x 70cm)

However the initial problem still stays the same. The navmesh is created at the start of the application and stays in world space at (0,0,0) and does not translate once the parent gameobject is placed on an image marker.



I can however test the game in Simulation view if I place the simulated Marker at (0,0,0) aswell and then it works.



There is a possible solution. I could try to recalculate the Navmesh manually once the gameobject is placed on the marker or once I press a Play-Button.

A* Pathfinfing provides this funcion:

Code (CSharp):

1. // Recalculate all graphs
2. AstarPath.active.Scan();

Where do you think I should put this script? Somewhere inside the existing MARS scripts after MARS has successfully identified the marker and placed the object? Or someplace else?

I don't know any C# unfortunatly and I don't feel comfortable doctoring around in the MARS scripts. So a detailed solution would be most welcome. Thank you.

 

@jmunozarUTech and @unity_andrewm did you get a chance to look at my last post?

 

@jmunozarUTech no worries. You've been a huge help already.



So in here would go the custom script, am I right?

Like I said I don't know how to write something like that. My C# skills are non existent. I'm trying to call this function of the A* Pathfinder.

Code (CSharp):

1. // Recalculate all graphs
2. AstarPath.active.Scan();

Graph Updates during Runtime - A* Pathfinding Project (arongranberg.com)

It's probably super easy for somebody who knows his C#. Do you know where I could ask for somebody to write this for me?

Thanks again.

 

Dear @jmunozarUTech I made a huge step forward thanks to you. Thank you kindly.