fix crash when recording, because the audioregion view has no frame handles
basically operational switch to canvas drawing coordinates, although text and waves don't work, and redraw areas are too small
fix rect redraw problems caused by intersection requiring the usual 0.5 expansion (though consider a more general fix for this at teh group level)
switch samples_per_pixel to integer type
initial semi-working attempt at getting waveview cache to work correctly
inching pretty close to fully working waves now