/*
    an overhaul of Gravity

    as before, you can click and move the base or
    the tip of the gravity arrow to adjust its position,
    direction and strength.

    to (auto) animate the gravity arrow:

      assign a drone to base of gravity
      assign another drone to tip of gravity

      move or visual FM / AM modulate one or both these drones
      and gravity moves accordingly.

      animating gravity influences the trajectory of launched
      drones :)

    click 'Base to manual' and 'Tip to manual' to detach
    assigned drones from base and the tip respectively.

    you can now manually edit the base and tip again.

    click 'Select base', 'Select tip' or 'Select both'
    to select the assigned drones. Useful for moving,
    for visual AM/FM, to mute them etc.

    eg., you could mute the assigned drones by clicking
    'Select both' and then Menu > Drone Tools > Mute

/*

/* adjust position/phase of visual drone modulation (AM and FM)

    Menu > Drone Params > AM Position
    Menu > Drone Params > FM Position

    eg., at 0 position with AM and FM BPMs equal, the trail/path
    of the modulating drones is elliptical.

/* set AM BPM to FM BPM of drones and vice-versa
/* flip velocity direction of launched drone with respect to the launcher
   if -ve flag is set in drone velocity defaults
/* opacity parameter for oscilloscope
* optimised oscilloscope
  * faster sample add
  * faster drawing
* changed shape of drone handles
* optimised snap lines drawing on curve editors
! fixed OpenGL drawing bugs for affected OpenGL drivers on Windows !
  ! in oscilloscope !
  ! in waveform display on waveform editors !
  ! when hz/vol displayed on drones !
! fixed crash if drones as they are fading in when creating drone mesh
  are modulated or moved !