Class Manipulators.trackball

class trackball : < mouse : < affect : Event.mouse_listener -> unit; .. >;
         ticker : < affect : Event.frame_listener -> 'a; .. >; .. > -> object .. end

** note: trackball is broken because the actuator system is in need of upkeeping **

The following code creates a cube that can be rotated by dragging the mouse.

	open FatCaml.Application
	
	let event_dispatcher = display_singleton#event_dispatcher in
	
	let cube = new cube and
	    rotation = new rotation_actuator and
	    trackball = new trackball event_dispatcher in

	trackball#affect (rotation :> scaleable_2d)
	rotation#affect  (cube :> gl_node) ;
	

• Scene.affector
• Event.mouse_listener
• Event.frame_listener

val mutable autospin : bool

val mutable dx : int

val mutable dy : int

method mouse_pressed : Sdlevent.mousebutton_event -> unit

method mouse_released : Sdlevent.mousebutton_event -> unit

method mouse_moved : Sdlevent.mousemotion_event -> unit

method mouse_dragged : Sdlevent.mousemotion_event -> unit

method do_tick : unit