On June 15, 2010 02:40:30 pm James Morris wrote:
Perhaps more importantly, be able to detect the exact time the notes occurred
and be able to observe quick, short note or controller changes not visible by
If it is desired to visually observe events shorter than the screen refresh
rate can show, how about a 'scope trace' or 'chart recorder' style box?
Say 100 horizontal pixel positions on the graph represents 1/60 second
(the refresh rate of most LCDs).
Thus each pixel position represents 1/100 of 1/60 second.
The vertical graph positions represent some data, midi CC value for example.
Thus the entire graph box need only be updated every 1/60 second,
or even less if say 200 pixels, representing 1/30 second, are used,
and so on...
If a graph is not desirable, say a knob or slider control instead,
then another idea is to change the colour of the control
indicating something quick happened, say for example a quick
change to a new value and then quickly back to the previous value,
which your eyes, and monitor, would not have noticed.
It's an important change nonetheless, because your ears heard it.
Perhaps some meaning could be conveyed through the actual colour used.
Perhaps a digital number on the control face indicating how many events
Although you might want to smooth this by only updating
once per second for example.
The idea is to 'latch' detection of short events, for longer display later.
Because even if you had a monitor with a very high refresh rate,
your eyes still aren't going to detect short events, so it's pointless
to only display the event for just that brief period, no?
But with those methods, it's a question of how often you want the
control's colour or number to change, or even if you want to
manually 'reset' them after having been informed of the changes.
You could get fancy by making 3D controls, where the depth
conveys some information.
Say a knob which is actually 100 knobs stacked depth-wise.
The 100 knobs represent all the changes during 1/60 second.
You could rotate the whole assembly to view it as a sort of 'graph',
or rotate it 'normally' to just show the front knob representing the most
OK, well that's a bit far fetched, but...
(Just a few ideas born while thinking of how to display live oscilloscope
traces on an LCD monitor, so this discussion of displaying live data
on slow refresh devices interests me...)
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