[Solved] Unable to get feature points with ARPointCloud.Positions?

In update I'm trying to get all of the feature points currently detected.

In AR foundation v1.0

Code (CSharp):

1. List<Vector3> featurePoints = new List<Vector3>();
2. arPointCloud.GetPoints(featurePoints, Space.Self);

with v2.2 I've tried

Code (CSharp):

1. List<Vector3> featurePoints = new List<Vector3>(arPointCloud.positions);
2.  

I must be doing something wrong here. Any advice?

edit: My logcat is bombarded with this error
E/native: hit_test.cc:376 generic::internal: No point hit.

 

Still can't get it to work. Any help is highly appreciated.

Code (CSharp):

1. //get the arPointCloud
2. ARPointCloud arPointCloud = arSessionOrigin.trackablesParent.GetComponent<ARPointCloud>();
3. //check for existence of points
4. if (arPointCloud.positions.IsCreated)
5. {
6. //add points to list
7. List<Vector3> featurePoints = new List<Vector3>(arPointCloud.positions);
8. }

 

[Solved]

ARPointCloud

is generated as a child of the

trackablesParent

transform so you need to use

trackablesParent.GetComponentInChildren<ARPointCloud>()

 

Thanks ! what arfoundation version did you use?

I'm on "com.unity.xr.arfoundation": "2.1.0-preview.2", "com.unity.xr.arkit": "2.1.0-preview.3" , this solution does nto work for me, ARPointCloudManager does not seem to instantiate at m_SessionOrigin.trackablesParent in ARPointCloudManager script. Running this code I get obj ref not set to instance of an object.

I see "com.unity.xr.arfoundation": "1.1.0-preview.6", "com.unity.xr.arkit": "1.0.0-preview.23" may work that work because ARPointCloudManager instantiates at m_SessionOrigin.trackablesParent

I raised query at https://github.com/Unity-Technologies/arfoundation-samples/issues/223

 

I'm using all the newest preview packages v2.2

 

Thanks, am I doing this in line with your method?

on 2.1 I get NullReferenceException: Object reference not set to an instance of an object for

ARPointCloud myARPointCloud=GameObject.FindGameObjectWithTag("ARSessionOrigin").GetComponent<ARSessionOrigin>().trackablesParent.GetComponentInChildren<ARPointCloud>();

 

I'm assuming your "ARSessionOrigin" GameObject has the ARSessionOrigin and ARPointCloudManager components attached?
Then use this and add it to the same GameObject.

Code (CSharp):

1.  
2. //get the ARSessionOrigin component
3. arSessionOrigin = GetComponent<ARSessionOrigin>();
4. //get the ARPointCloud component
5. ARPointCloud arPointCloud = arSessionOrigin.trackablesParent.GetComponentInChildren<ARPointCloud>();
6. //check for existence of points
7. if (arPointCloud.positions.IsCreated)
8. {
9. //add points to list
10. List<Vector3> featurePoints = new List<Vector3>(arPointCloud.positions);
11. }

 

Cool @BuoDev , thanks a bunch ! That worked

I was getting the component at OnEnable and Session wasn't ready but couldn't see it so was getting null ref exception

indeed found there is no confidence data with arkit (not even zeros, just doesn't return nothing)

 

Ok, i really don't know what am i doing wrong. I tried everything and it doesnt work. Please help

This is my simple code:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEngine.XR.ARFoundation;
5. using UnityEngine.UI;
6.  
7. public class PointCloudList : MonoBehaviour
8. {
9.     [SerializeField]
10.     ARSessionOrigin arSessionOrigin;
11.     [SerializeField]
12.     ARPointCloud arPointCloud;
13.     [SerializeField]
14.     ARPointCloudManager arPointCloudManager;
15.  
16.     public Text featurePointText;
17.  
18.     void Start()
19.     {
20.         arSessionOrigin = GetComponent<ARSessionOrigin>();
21.         // arPointCloud = GetComponent<ARPointCloud>();
22.         arPointCloudManager = GetComponent<ARPointCloudManager>();
23.  
24.      
25.         arPointCloud = arSessionOrigin.trackablesParent.GetComponentInChildren<ARPointCloud>();
26.  
27.         Debug.Log(arPointCloud);
28.     }
29.  
30.     void Update()
31.     {
32.         // List<Vector3> featurePoints = new List<Vector3>(arPointCloud.positions);
33.         if (arPointCloud != null)
34.         {
35.             featurePointText.text = "arPointCloud.positions.IsCreated = True";
36.         }
37.     }
38. }

If i use "arPointCloud.positions.IsCreated", unity throws error. Probably, because arPointCloud is still null.
On my AR session origin Gameobject i have: ARSessionOrigin, ARPointCloud, ARPointCloudManager and my script PointCloudList.
Do i need ARPointCloud? Do i need ARPointCloudManager?
I tried all combinations, and also tried everything in code.
Oh, and this version doesnt throw error, but arPointCloud is always null.

I am using: Unity 2019.1.11f, AR Foundation 2.1.0 - preview.3, AR Core 2.1.0 - preview.5
I am trying to build on android (Galaxy S8+).

 

@sasob8 Try getting the PointCloud component in Update - it probably doesn't exist yet in Start. Also check for the actual positions after you know that the PointCloud component exists. This should work.

Code (CSharp):

1.  
2.     void Update()
3.     {
4.         // List<Vector3> featurePoints = new List<Vector3>(arPointCloud.positions);
5.      
6.         if (arPointCloud == null)
7.         {
8.             arPointCloud = arSessionOrigin.trackablesParent.GetComponentInChildren<ARPointCloud>();
9.         }
10.         else
11.         {
12.             if(arPointCloud.positions.IsCreated)
13.             {
14.             featurePointText.text = "arPointCloud.positions.IsCreated = True";
15.             }
16.         }
17.     }
18.  

 

thank you it works... now i understand how it works.