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Tracking And Camera Issues

6DoF Camera Motion Not Working​

Issue​

As I move my phone, the camera position does not update.

Resolution​

Check the position of the camera in your scene. The camera should NOT be at a height (Y) of zero. Set it to Non-Zero value. The Y position of the camera at start effectively determines the scale of virtual content on a surface (e.g. smaller y, bigger content)

Object Not Tracking Surface Properly​

Issue​

Content in my scene doesn't appear to be "sticking" to a surface properly

Resolution​

To place an object on a surface, the base of the object needs to be at a height of Y=0

Note: Setting the position at a height of Y=0 isn't necesarily sufficient.

For example, if the transform your model is at the center of the object, placing it at Y=0 will result in part of the object living below the surface. In this case you'll need to adjust the vertical position of the object so that the bottom of the object sits at Y=0.

It's often helpful to visualize object positioning relative to the surface by placing a semi-transparent plane at Y=0.

A-Frame example​

<a-plane
  position="0 0 0"
  rotation="-90 0 0"
  width="4"
  height="4"
  material="side: double; color: #FFFF00; transparent: true; opacity: 0.5"
  shadow>
</a-plane>

three.js example​

  // Create a 1x1 Plane with a transparent yellow material
  var geometry = new THREE.PlaneGeometry(1, 1, 1, 1);   // THREE.PlaneGeometry (width, height, widthSegments, heightSegments)
  var material = new THREE.MeshBasicMaterial({color: 0xffff00, transparent:true, opacity:0.5, side: THREE.DoubleSide});
  var plane = new THREE.Mesh(geometry, material);
  // Rotate 90 degrees (in radians) along X so plane is parallel to ground
  plane.rotateX(1.5708)
  plane.position.set(0, 0, 0)
  scene.add( plane );