Quote Originally Posted by redBeard View Post
You are correct here. We have tuned the refresh rate accordingly. I do have one instrument display, however, that is rather choppy looking at 16 - 20 frames/sec. It looks best at 25 - 30 frames/sec.
Are you reconstructing the path from scratch at every update?

QWidget flags? Which ones?
For example Qt::WA_OpaquePaintEvent and Qt::WA_StaticContents

I also found another CPU hog with my display code, as well. I have a nice looking linear gradient for background of the main instrument panel, using QLinearGradient, the parameters of which are set in the central widget resize() method. That's what our screen designer wanted.....

I found that no background reduced the CPU utilization dramatically - to about 10% on Linux when the overall instrument panel was maximized to full screen. That appears to be approaching QTimer overhead of the two timers I have. I'll see if i can use a static image instead for this and position it in the background according to the size of the overall instrument panel.
Cache the background.