Why getAllTrackables method return only one face?

Question

I'm running the arcore sample of new version (1.7.0).

In the sample of AugmentedFace, why below statement return only one face?

Collection<AugmentedFace> faceList =
          sceneView.getSession().getAllTrackables(AugmentedFace.class);

Did I miss something? or is it just kind of limitation?

Answer 1

ARCore's Augmented Faces feature was designed to work primarily with one face. But you can use it for more faces.

// Get a list of detected faces.
Collection<AugmentedFace> faceList = session.getAllTrackables(AugmentedFace.class);


for (AugmentedFace face : faceList) {

    // Create a face nodes and add it to the scene.
    AugmentedFaceNode faceNode1 = new AugmentedFaceNode(face);
    AugmentedFaceNode faceNode2 = new AugmentedFaceNode(face);
    faceNode1.setParent(scene);
    faceNode2.setParent(scene);

    // Overlay the 3D assets on faces.
    faceNode1.setFaceRegionsRenderable(faceRegionsRenderable1);
    faceNode2.setFaceRegionsRenderable(faceRegionsRenderable2);

    // Overlay textures on faces.
    faceNode1.setFaceMeshTexture(faceMeshTexture1);
    faceNode2.setFaceMeshTexture(faceMeshTexture2);
}