'PREVIOUS' Button


          Transform {
              ##translation  -0.5 -0.35 -1
              translation  -7 -3 0
              children [
                  DEF PREVIOUS_TOUCH_SENSOR TouchSensor {}
                  Transform {
                      rotation  1 0 0 1.57
                      scale 0.5 1.5 1
                      ##scal10  5  0.05 0.05 0.05
                      children  USE ARROW_SHAPE
                      ##children  USE SPHERE_SHAPE
                  }
              ]
          }