java如何在arCore平面中设置三维模型而无需点击

Question

我想在检测到平面时立即在弧心的随机部分上设置三维模型。不确定要使用哪种方法进行设置

addOnUpdateListener(this::onUpdate);

 private void onUpdate(FrameTime frameTime) {
    if (numOfModels > 0) return;
    modelLoader1 = new ModelLoader(weakReference);
    Frame frame = arFragment.getArSceneView().getArFrame();
    Collection<Plane> planes = frame.getUpdatedTrackables(Plane.class);
    for (Plane plane : planes) {
        if (plane.getTrackingState() == TrackingState.TRACKING) {
            addObject(Uri.parse("andy_dance.sfb"));
            break;
        }
    }
}

private void addObject(Uri model) {
    Frame frame = arFragment.getArSceneView().getArFrame();
    安卓.graphics.Point pt = getScreenCenter();
    List<HitResult> hits;
    if (frame != null) {
        hits = frame.hitTest(pt.x, pt.y);
        for (HitResult hit : hits) {
            Trackable trackable = hit.getTrackable();
            if (trackable instanceof Plane &&
                    ((Plane) trackable).isPoseInPolygon(hit.getHitPose())) {
                modelLoader1.loadModel(hit.createAnchor(), model);
                break;

            }
        }
    }
}

public void loadModel(Anchor anchor, Uri uri) {
    if (owner.get() == null) {
        Log.d(TAG, "Activity is null.  Cannot load model.");
        return;
    }
    ModelRenderable.builder()
            .setSource(owner.get(), uri)
            .build()
            .handle((renderable, throwable) -> {
                MainActivity activity = owner.get();
                if (activity == null) {
                    return null;
                } else if (throwable != null) {
                    activity.onException(throwable);
                } else {
                    activity.addNodeToScene(anchor, renderable);
                }
                return null;
            });

    return;
}

public void addNodeToScene(Anchor anchor, ModelRenderable renderable) {
    numOfModels++;
    AnchorNode anchorNode = new AnchorNode(anchor);
    TransformableNode node = new TransformableNode(arFragment.getTransformationSystem());
    node.setRenderable(renderable);
    node.setParent(anchorNode);
    node.setLocalPosition(new Vector3(0f, 0f, 0f));
    modelLoader1.setNumofLivesModel0(2);
    arFragment.getArSceneView().getScene().addChild(anchorNode);

    setNodeListener(node, anchorNode, modelLoader1);

到目前为止，我能够用一个模型填充屏幕，但是在屏幕的中心，如果可能的话，我们现在想把模型设置在角落里

Answer 1

在活动开始时，我实例化了一个新的Vector3对象，以便以后可以将其用于3d模型定位：

vector = new Vector3();

通过实现一个ARCore认为是手机位置的世界锚，我们找到了答案：

AnchorNode anchorNode = new AnchorNode();
    anchorNode.setWorldPosition(new Vector3(0, 0, 0));

有了AnchorNode集合，我们就能够在世界上定位一个物体，知道它实际上会在哪里

vector.set(randomCoordinates(true), randomCoordinates(false), -.7f);

AnchorNode anchorNode = new AnchorNode();
    TransformableNode node = new TransformableNode(arFragment.getTransformationSystem());
node.setRenderable(ModelRenderable);
node.setParent(anchorNode);
node.setWorldPosition(vector);

向量接受的参数。set（）是三个浮点数，分别是x、y、z坐标。为了让3d模型显示在相机前面，建议x坐标在-300到.300之间，y坐标在-500到.500之间，z坐标在-7到1之间