SFML using 3-2 times as much CPU when hidden behind another window?

[Gan]

I'm running on a Mac and compiled my project using MonoD with D-SFML.

When I have my window completely hidden behind another window, CPU usage goes from 10% to 30%. I noticed it because my laptop's fans started whirring. If the window is slightly visible, CPU is 10%. As soon as I make the window completely not visible, it goes to 30% CPU usage.

It's not a serious problem but it is making my curious. Why does this happen?

[eXpl0it3r]

Do you limit your framerate?

[Gan]

No. I have it set up like the example program. A while loop for when the window is open. In that while loop I handle events, logic and drawing the window.

[Hiura]

What is probably happening is that the drawing is optimised out; then your program is no longer waiting (i.e. idle) on the display() call but instead is working on something.

[Gan]

Oh. So I should make the thread sleep if it's going faster than 60fps?

[Hiura]

http://www.sfml-dev.org/documentation/2.2/classsf_1_1Window.php#af4322d315baf93405bf0d5087ad5e784 does it for you.

[Gan]

Yay that fixed it.