Scrolling Display


#1

hi guys,
i have a child class in that i’m trying to make an scrolling display for some incoming events (lets say midi) in the style of 0(for no event) and 1(for an event) like an square oscillator (or digital-clock-divider-something).
what would be the best solution of doing this. or perhaps there is already something premade in the lib i can use?
sorry for noob questions here in this highly professional forum!
but i’m musician and enjoy really this framework!
cheers!


#2

You can copy the messages to a FIFO (the AbstractFifo class works well for this, add it as a class member). When you receive the message, push it to the top of the fifo. In your component, derive it from the timer base class and call repaint in the callback. In the paint method, just read through the fifo to display the messages however you like. A more efficient way to do this is to use an image and only draw to a portion of the image and shift it during the timer callback.

I will say if you’re using MIDI a list of events is more useful than a scrolling oscilloscope/logic scope.


#3

many thanks! is this possible to show a simple example on how to do this with the image?