In-ground light fixtures, for example, direct the light up towards the 180 degree vertical (zenith), whereas area light fixtures on a pole direct light down towards the 0 degree vertical (nadir). Many light fixtures come with asymmetrical light output, e.g. wall wash optics in in-ground fixtures, and forward throw patterns in area light fixtures. Usually the primary aiming direction of the light fixture in these cases is set to 0 degree horizontal.

3dOP Pro indicates the 0 degree horizontal direction with a blue or green arrow head next to the blue or green square representing the location of the light fixture on the grid. When the light fixture is initially loaded into 3dOP Pro the fixture horizontal 0 degree direction is always set to point in the positive X direction, as illustrated below.

Initial placement of fixture	move 3ft in Z	rotate 90 degrees in Y

In the second illustration the in-ground fixture has been moved back 3 feet from the wall grid in the +Z axis. Notice the light coming from the side of the fixture. The 90 degrees horizontal direction is aiming perpendicular to the wall.

In the final illustration the fixture has been rotated 90 degrees counter clockwise to point the 0 degree horizontal angle of the fixture directly at the wall.

3dOP Pro grid coordinates are shown below: