AR Core object detection

Unity Engine
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1

Hey, quick question. Has anyone had any luck with detecting an object as of yet?

In the HelloWorld example, you can access the out hit param as you would with a normal raycast. But it has no information entailing what game object it hit. For example hit.trasform.gameobject.tag

2

Raycasts in ARCore hit (real world) planes, not game objects. You can see the plane that is hit in the Plane member of TrackableHit.

1 Like
3

Is there any way of detect the game object?

4

To raycast against GameObjects, you can continue to use Physics.Raycast.

5

I have tried to use Physics.Raycast on Andy object from HelloArExample, but it is not hitting anything. Below is my script.

Ray raycast = m_firstPersonCamera.ScreenPointToRay(touch.position);
            RaycastHit raycastHit;
            if (Physics.Raycast(raycast, out raycastHit))
            {
                Debug.LogError("Something Hit");
                if (raycastHit.collider.name == "Andy")
                {
                    Debug.LogError("andy clicked");
                }
            }else{
                Debug.LogError("No hit detected");
            }

So, I have edited HelloARController.cs script. Here m_firstPersonCamera is the ARCamera used by Google ARCore, Even though I click on Andy object, it always goes to the else part of first if condition.

Can you please check if I am missing anything?

6

any luck on this?

7

Hi, I found this sample project on github which does object detection on ar plane, but it is in android studio.

8

OK, I have finally figured out why Physics.Raycast not working correctly with andy object. It is by correctly setting box collider. Below are the correct steps to make a ray hit the andy object.

  1. Add box collider component to andy prefab
  2. set center of the box collider as: x:0, y:0.1, z:0
  3. set size of the box collider as: x:0.15,y:0.2,z:0.1

Or you can set this values visually by drag and drop andy prefab to unity scene editor.

Hope this helps.

9

GameObjects need to have colliders in order for raycast to see them, even in ARCore.
Physics.Raycast out hit and then hit.collider.gameObject can be used to access the GameObject.