Method SetGroundLocal

isis/src/base/objs/Sensor/Sensor.cpp:477–517

* This method handles the common functions for the overloaded SetUniversalGround methods. * Instead of computing a point on the target, a point is set (lat,lon,radius) and the look * direction is computed. * * @param backCheck If true this method will check the lat/lon point to see if * it falls on the backside of the target (or beyond the * horizon).

  *   @history 2017-03-23 Kris Becker - Added formal occlusion callback
  */
  bool Sensor::SetGroundLocal(bool backCheck) {
    ShapeModel *shape = target()->shape();
    // With the 3 spherical value compute the x/y/z coordinate
    //latrec_c(m_radius, (m_longitude * PI / 180.0), (m_latitude * PI / 180.0), m_pB);


    if (!(shape->hasIntersection())) {
      return false;
    }

    // Make sure the point isn't on the backside of the body

    // This is static purely for performance reasons. A significant speedup
    // is achieved here.
    const vector<double> &sB =
        bodyRotation()->ReferenceVector(instrumentPosition()->Coordinate());

    m_lookB[0] = shape->surfaceIntersection()->GetX().kilometers() - sB[0];
    m_lookB[1] = shape->surfaceIntersection()->GetY().kilometers() - sB[1];
    m_lookB[2] = shape->surfaceIntersection()->GetZ().kilometers() - sB[2];
    m_newLookB = true;

    // See if the point is on the backside of the target. Note occlusion handling
    // now handles this in derived shape models that can support it. (KJB 2017-03-23)
    // This may be good if the computation of the look direction is more sophisticated.
    if (backCheck) {
      // Assume the intersection point is good in order to get the emission angle
      // shape->setHasIntersection(true);  //KJB there should be a formal intersection in ShapeModel
      std::vector<double> lookdir = lookDirectionBodyFixed();
      if ( !shape->isVisibleFrom(sB, lookdir) ) {
        shape->clearSurfacePoint();
        shape->setHasIntersection(false);
        return false;
      }
    }

    // return with success
    shape->setHasIntersection(true);

    return true;
  }


  /**