Is ARGeoTrackingConfiguration always more accurate than ARWorldTrackingConfiguration for world scale AR?

Question

cht1995 OP

Created Jan ’24

Replies 2

Boosts 0

Participants 2

We are working on a world scale AR app that leverages the device location and heading to place objects in the streets, so that they are correctly and stably anchored to certain locations.

Since the geo-tracking imagery is only available in certain cities and areas, we are trying to figure out how to fallback when geo-tracking is not available as the device move away, to still retain good AR camera accuracy. We might need to come up with some algorithm using the device GPS, to line up the ARCamera with our objects.

Question: Does geo-tracking always provide greater than or equal to the accuracy of world tracking, for a GPS outdoor AR experience?

If so, we can simply use the ARGeoTrackingConfiguration for the entire time, and rely on the ARView keeping itself aligned. Otherwise, we need to switch between it and ARWorldTrackingConfiguration when geo-tracking is not available and/or its accuracy is low, then roll our own algorithm to keep the camera aligned.

Thanks.

Answered by Technology Evangelist in 777662022

Both these configurations are currently supported on iOS only.

ARGeoTrackingConfiguration is primarily used for detecting real world building geometry alongside using GPS information and map data to help localize an experience with respect to a building / outdoor location.

ARWorldTrackingConfiguration on the other hand doesn't depend on GPS, MapData or building geometry and works both indoors and outdoors. It primarily helps with understanding a space for overlaying virtual content (i.e. placing 3D models) on top of real world surfaces / objects.

Boost

Answer 1

Technology Evangelist OP

Apple

Jan ’24

Accepted Answer

Both these configurations are currently supported on iOS only.

ARGeoTrackingConfiguration is primarily used for detecting real world building geometry alongside using GPS information and map data to help localize an experience with respect to a building / outdoor location.

ARWorldTrackingConfiguration on the other hand doesn't depend on GPS, MapData or building geometry and works both indoors and outdoors. It primarily helps with understanding a space for overlaying virtual content (i.e. placing 3D models) on top of real world surfaces / objects.

0

Answer 2

cht1995 OP

Jan ’24

Thanks for your response. That doesn't quite answer my question though.

Before ARGeoTrackingConfiguration was available in ARKit 4, we used to use ARWorldTrackingConfiguration and a custom method to periodically calibrate/sync the location between the AR view and our 3D-map scene view, so our scene doesn't drift too much in regards to the AR camera feed, as the device move around 10+ meters.

With the addition of ARGeoTrackingConfiguration and when street imagery/geo-anchors are available on the main streets, we now find the accuracy of ARFrame camera really good, resulting in smooth experience and much less calibration needed. 👍

However, when street imagery aren't available, say we move from a main street into a neighborhood, so the geo-tracking accuracy drops from medium to low or even undetermined, we need to fallback to something.

The question is: should we fallback to a new session with ARWorldTrackingConfiguration and use our old periodic calibration approach, or should we keep using ARGeoTrackingConfiguration and add some custom calibration logic to compensate for the low/undetermined accuracy?

It largely depends on if the session(_:didUpdate:) method in geo-tracking configuration always provides the accuracy as good as or better than world tracking. In other words, is geo-tracking a superset of features of world tracking in this regard?

From our own ad-hoc testing, we cannot tell for sure. 🫤 It almost seems like when street imagery isn't available, geo-tracking's accuracy sometimes is worse than world tracking, though only by a small margin. Also we found that when geo-tracking is trying to re-localize using street imagery, the ARFrame's camera might be unstable for a short period.

To sum up, we want to smoothly handle the case when geo-tracking starts to become unstable, or street imagery based geo-tracking is completely unavailable, to use custom logics to keep our scene aligned with the AR view. Is it possible to achieve it solely with a session configure with ARGeoTrackingConfiguration?

0