Anchors

This page is a supplement to the AR Foundation Anchors manual. The following sections describe the optional features of AR Foundation's XRAnchorSubsystem supported by ARCore.

Tip

When developing an AR app, refer to both the AR Foundation documentation as well as the required packages for each platform you support.

Optional feature support

ARCore implements the following optional features of AR Foundation's XRAnchorSubsystem:

Feature	Descriptor Property	Supported
Trackable attachments	supportsTrackableAttachments	Yes
Synchronous add	supportsSynchronousAdd	Yes
Save anchor	supportsSaveAnchor
Load anchor	supportsLoadAnchor
Erase anchor	supportsEraseAnchor
Get saved anchor IDs	supportsGetSavedAnchorIds
Async cancellation	supportsAsyncCancellation

Note

Refer to AR Foundation Anchors platform support for more information on the optional features of the anchor subsystem.

Native pointer

XRAnchor.nativePtr values returned by this package contain a pointer to the following struct:

typedef struct UnityXRNativeAnchor
{
    int version;
    void* anchorPtr;
} UnityXRNativeAnchor;

This package also provides a header file containing the definitions of various native data structs including UnityXRNativeAnchor. It can be found in the package directory under Includes~/UnityXRNativePtrs.h.

Cast void* anchorPtr to an ArAnchor handle in C++ using the following example code:

// Marhshal the native anchor data from the XRAnchor.nativePtr in C#
UnityXRNativeAnchor nativeAnchorData;
ArAnchor* anchorHandle = static_cast<ArAnchor*>(nativeAnchorData.anchorPtr);

To learn more about native pointers and their usage, refer to Extending AR Foundation.