Fast Graphics for Emdebian Kernel on BeagleBoneBlack
I'm looking for the most efficient (fastest) way to animate a set of audio level meters. I need to draw 16 of them, approximately 10 pixels wide by 400 pixels high - all of them independent from the other, of course.
The current target is a Beagle Bone Black platform running an Emdebian kernel and file system, using Qt 5.3 and QML 2.2. Using just basic QML to render simple rectangles of various heights takes about 50-70% of the BBB CPU cycles. I need to get that down to 20% or less.
I've tried writing to QCanvas as well, and can get into the 30% range.
I'm about to try SceneGraph (raw OpenGL - yikes!), and maybe even resort to QPainter (though I gather that is a step backwards).
The part that really gets me is if I try any of the example animation programs (Qt Quick Examples - Animation) on the BBB platform, they take anywhere from 50%-90% of the processor. The pong example is a good one - it is simply moving a small rectangle around on the screen, and it runs at 60-75%. I'm beginning to think that maybe Qt just isn't fast enough for what I need, or I'm missing some key component in the BBB file system that would accelerate the graphics rendering capabilities of QT.
I will also post in StackOverflow.