Oops, LOL. And the call to the function is thus:

while(is_run() {
	int circ1ang = 1;
	for (int i = 0; i <= 360; i++) {
	StartFpsTimer();
	PrintTitleText();
	circ1ang += CircleOrbit2(Mid.x, Mid.y, Mid.x - 100, Mid.y, 30, 2, false, circ1ang, clr::RED);
	SwapPages();
	CalculateFps();
	if (UserInput(…

You can use those, but then you have to call ValidateRect manually.

@rafaelsantana 

It occured to me that that might be a problem if there are more graphical effects happening at once. I'm slowly improving the program little by little.

EDIT: sorry for double-post.

d h k said:
Maybe I could also sleep for, say, half the frame time

That puts you right back at the mercy of the OS task scheduler, which was part of the problem to begin with. The default scheduler in Windows is about a full frame in duration. Any sleep at all, even those based on higher resolution …