Can I limit the frequency of screen-refresh?

Question

Hello EW Team,

The osd-refresh frequency of my playform is limited below 30fps, but ew thread can run faster(60hz or higher). If ew update a buffer, but I cannot pass it to my osd-refresh function, then this frame may be dropped.

Can  I limit the frequency of screen-refresh in EW? In this way, the ew thread can run normally (handle signals/ events ....) in higher frequency, and the osd-refresh on my device can run in lower fps.

Thanks!

Answer 1

Hello,

according to your description I assume that you are working with a double-buffered framebuffer scenario. If your display is operating with 30 Hz, the maximum number of framebuffer updates is limited to 30fps, because the framebuffer exchange can happen only on V-sync. This means, the entire GUI application cannot prepare more than 30 frames per second, because it is only possible to present 30 frames per second.

Please have a look to our documentation about the main loop, which describes the clear order of processing events / timers / signals, the update of the display, .... 

Due to the fact that the display update is synchronized to the V-sync, the entire main loop will synchronize to this speed.

Let me know if you see any issues with this approach.

Best regards,

Manfred.