title: How do I get the forward (LookAt) vector of the camera in ARKit?
body: <p>I am trying to get the forward (LookAt) vector of the camera in ARKit, but I think I getting something wrong.</p>
  <p>After doing some research, I wrote this helper extension below, but I don't think it is right from the data I am getting.  (The Y-Component is negative when I point the camera upwards).</p>
  <p>Can someone let me know what I getting wrong about getting the vector the camera is pointing in world space?  Also, if there is a better way to get it (CoreLocation?) I am open to that too.</p>
  <pre><code>extension ARCamera {
      /**
      The Camera forward orientation vector as vector_float3.
      */
      var forward: vector_float3 {
          get {
              return vector_float3(-1 * self.transform.columns.3.x,
                                   -1 * self.transform.columns.3.y,
                                   -1 * self.transform.columns.3.z)
          }
      }
  
      /**
      The Camera forward orientation vector as vector_float3 normalized.
      */
      var normalForward: vector_float3 {
          get {
              let theNormaled = simd_normalize(vector_float3(-1 * self.transform.columns.3.x,
                                                             -1 * self.transform.columns.3.y,
                                                             -1 * self.transform.columns.3.z))
              return theNormaled
          }
      }
  }
  </code></pre>
  <p>Thanks in advance.</p>
  <p>Stan</p>