 			_thetaStep = value;
 		}
 		
+		/**
+		 * Vertical angular step applied to the camera when the mouse is moved in radian/pixel
+		 */		
 		public function get phiStep() : Number
 		{
 			return _phiStep;

		private var _thetaStep			: Number	= 0.01;
		private var _phiStep			: Number	= 0.01;
		
		public function get distance() : Number
		{
			return _distance;

			// compute position
			if (e.buttonDown)
			{
				_theta	+= (_mousePosition.x - e.stageX) * _thetaStep;
				_phi	+= (_mousePosition.y - e.stageY) * _phiStep;
				
				_update = true;
			}
