Click and drag to rotate the camera.  
  Control-click and drag to zoom in/out.  
  Right-click and drag to translate the camera.  
     
  Shift-click on a charge element to highlight it and its corresponding vector at the observation point..  
     
  UP Arrow: Move observer in the Z direction.  
  DOWN Arrow: Move observer in the -Z direction.  
  RIGHT Arrow: Move observer in the Y direction.  
  LEFT Arrow: Move observer in the -Y direction.  
  CONTROL + UP Arrow: Move observer in the X direction.  
  CONTROL + DOWN Arrow: Move observer in the -X direction.  
     
  I: Show/Hide instructions.  
  M: Show/Hide field map