how to group multiple 3d objects as one using AR core

Question

here i am displaying multiple 3d object in scene (check below pic )

and here i am having 3 3d model objects and now is it possible to to group the the 3d model objects ex. if i move one 3d object then other 2 3d objects also needs to move .Is it possbile to achieve this with out using the unity & cloud anchors

below is my code

package com.google.ar.sceneform.samples.hellosceneform;

import android.app.Activity;
import android.app.ActivityManager;
import android.content.Context;
import android.os.Build;
import android.os.Build.VERSION_CODES;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.Gravity;
import android.view.MotionEvent;
import android.widget.Toast;
import com.google.ar.core.Anchor;

import com.google.ar.core.HitResult;
import com.google.ar.core.Plane;
import com.google.ar.sceneform.AnchorNode;
import com.google.ar.sceneform.rendering.ModelRenderable;
import com.google.ar.sceneform.ux.ArFragment;
import com.google.ar.sceneform.ux.TransformableNode;


public class HelloSceneformActivity extends AppCompatActivity {
  private static final String TAG = HelloSceneformActivity.class.getSimpleName();
  private static final double MIN_OPENGL_VERSION = 3.0;

  private ArFragment arFragment;
  private ModelRenderable andyRenderable;

  @Override
  @SuppressWarnings({"AndroidApiChecker", "FutureReturnValueIgnored"})

  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    if (!checkIsSupportedDeviceOrFinish(this)) {
      return;
    }

    setContentView(R.layout.activity_ux);
    arFragment = (ArFragment) getSupportFragmentManager().findFragmentById(R.id.ux_fragment);

    // When you build a Renderable, Sceneform loads its resources in the background while returning
    // a CompletableFuture. Call thenAccept(), handle(), or check isDone() before calling get().
    ModelRenderable.builder()
        .setSource(this, R.raw.andy)
        .build()
        .thenAccept(renderable -> andyRenderable = renderable)
        .exceptionally(
            throwable -> {
              Toast toast =
                  Toast.makeText(this, "Unable to load andy renderable", Toast.LENGTH_LONG);
              toast.setGravity(Gravity.CENTER, 0, 0);
              toast.show();
              return null;
            });

    arFragment.setOnTapArPlaneListener(
        (HitResult hitResult, Plane plane, MotionEvent motionEvent) -> {
          if (andyRenderable == null) {
            return;
          }

          // Create the Anchor.
          Anchor anchor = hitResult.createAnchor();
          AnchorNode anchorNode = new AnchorNode(anchor);
          anchorNode.setParent(arFragment.getArSceneView().getScene());

          // Create the transformable andy and add it to the anchor.
          TransformableNode andy = new TransformableNode(arFragment.getTransformationSystem());
          andy.setParent(anchorNode);
          andy.setRenderable(andyRenderable);
          andy.select();
        });
  }


  public static boolean checkIsSupportedDeviceOrFinish(final Activity activity) {
    if (Build.VERSION.SDK_INT < VERSION_CODES.N) {
      Log.e(TAG, "Sceneform requires Android N or later");
      Toast.makeText(activity, "Sceneform requires Android N or later", Toast.LENGTH_LONG).show();
      activity.finish();
      return false;
    }
    String openGlVersionString =
        ((ActivityManager) activity.getSystemService(Context.ACTIVITY_SERVICE))
            .getDeviceConfigurationInfo()
            .getGlEsVersion();
    if (Double.parseDouble(openGlVersionString) < MIN_OPENGL_VERSION) {
      Log.e(TAG, "Sceneform requires OpenGL ES 3.0 later");
      Toast.makeText(activity, "Sceneform requires OpenGL ES 3.0 or later", Toast.LENGTH_LONG)
          .show();
      activity.finish();
      return false;
    }
    return true;
  }
}

Answer 1

You can group 3D objects together by using the .setParent() method. When an object is transformed (moved, rotated, or scaled), the child objects are also transformed.

The Solar System sample demonstrates this in createSolarSystem(). The planets are made children of the sun, and the moon is made a child of the Earth node.

You can then position the object relative to the parent by using setLocalPosition(). Such as positioning the planet in solarActivity:

Planet planet =
    new Planet(
        this, name, planetScale, orbitDegreesPerSecond, axisTilt, renderable, solarSettings);
planet.setParent(orbit);
planet.setLocalPosition(new Vector3(auFromParent * AU_TO_METERS, 0.0f, 0.0f));