/// <summary>
/// Make this camera look at a specific point in the world.
/// </summary>
/// <param name="position">The point to look at.</param>
public void LookAt(Vector3 position)
{
//store the line between the camera and the other IPoint3D, but only on the X/Z plane, then normalize it to get a unit vector.
Vector2 pitchVec = Vector2.Normalize(new Vector2(position.X - Position.X, position.Z - Position.Z));
//convert vector to angle and roatate the right axis to that angle
RotatePitchTo((float)(Math.Atan2(pitchVec.Y, pitchVec.X) * (180f / MathHelper.Pi) - 90));
//update lookAxis, the normalized vector of the line between this camera and the IPoint3D.
lookAxis = Vector3.Normalize(Vector3.Subtract(position, Position));
//update the heading variable and upAxis
RotateHeadingTo((float)Math.Asin(-lookAxis.Y) * (180f / MathHelper.Pi));
//update the view matrix so our changes are reflected in the world
RebuildView();
}
