ARKit - ARCore 多人定位问题

Question

I'm trying to make a simple ARKit / ARCore multiplayer app in Unity, using Photon according to this tutorial .

It works fine in general, but there is one strange problem.

I use two smartphones - iPhone and Android devices. When I place my 3D scene in the real world space for the first time using one of my smartphones (doesn't matter which) and then launch multiplayer everything is fine.

When I position my 3D scene using the second smartphone it's also fine. But when I launch multiplayer on the second smartphone the whole scene jumps to a different location on this smartphone.

I tried to understand why is it happening, I think when the second smartphone joins multiplayer, it receives information about the position of the 3D scene from the first smartphone, and some differences in coordinate systems cause this error.

How can I fix it?

Answer 1

I suppose, the best way to organize a robust multiuser AR experience is to follow the Apple's main principles of World Map Sharing: Creating a Multiuser AR Experience . Pay particular attention if Unity supports the latest World Map and Multiuser features for both: iOS and Android.

It's also good to use positioning markers to help Operating Systems to locate a user in World Map.

But remember, the sensors of iOS devices and Android devices are calibrated slightly differently!

To find out more useful information about AR and sensors calibration, read my answer in SO post: Are there any limitations in Vuforia compared to ARCore and ARKit? .