5bdc869e49
There is a highly unlikely case where the render thread can have zero requests in the queue, but it is not supposed to be terminated. 1) WaveView::queue_get_image(); wake up thread, *but* the thread does not start yet 2) WaveView::cancel_my_render_request(); and now the thread starts. 1,2 are initiated by user actions from the GUI thread and are normally orders of magnitude slower than scheduler-thread wakeup.
Please see the Ardour web site at http://ardour.org/ for all documentation..
For information on building ardour:
http://ardour.org/development.html