     return unless @_touchEnabled
     e.preventDefault()
     # Set a reference to the current x or y position.
-    # Cancel if the mouse button isn't down.
     if e.type is 'mousemove'
-      return if e.which isnt 1
       current = e["page#{ @_touchAxis.toUpperCase() }"]
     else
       current = e.targetTouches[0]["page#{ @_touchAxis.toUpperCase() }"]

    # If the speed value is `true` reset the speed to the original settings.
    # Set it to zero if `false`.
    if typeof speed is 'boolean'
      speed = if speed then @settings.speed + 'ms' else '0'

    # To loop through the shaders, derive the correct pair from the current anchor.
    if @lastAnchor is 'left' or @lastAnchor is 'right'

    else
      @["_#{ @_touchAxis }1"] = e.targetTouches[0]["page#{ @_touchAxis.toUpperCase() }"]

    # Add movement listener.
    @stageEl.addEventListener 'touchmove', @_onTouchMove, false
    @stageEl.addEventListener 'mousemove', @_onTouchMove, false

    # Return that value to an external listener.
    @settings.touchStartCallback @["_#{ @_touchAxis }1"]

