I can't figure out why this fps counter is inaccurate.
- by rmetzger
I'm trying to track frames per second in my game. I don't want the fps to show as an average. I want to see how the frame rate is affected when I push keys and add models etc. So I am using a variable to store the current time and previous time, and when they differ by 1 second, then I update the fps.
My problem is that it is showing around 33fps but when I move the mouse around really fast, the fps jumps up to 49fps. Other times, if I change a simple line of code elsewhere not related to the frame counter, or close the project and open it later, the fps will be around 60. Vsync is on so I can't tell if the mouse is still effecting the fps.
Here is my code which is in an update function that happens every frame:
FrameCount++;
currentTime = timeGetTime ();
static unsigned long prevTime = currentTime;
TimeDelta = (currentTime - prevTime) / 1000;
if (TimeDelta > 1.0f)
{
fps = FrameCount / TimeDelta;
prevTime = currentTime;
FrameCount = 0;
TimeDelta = 0;
}
Here are the variable declarations:
int FrameCount;
double fps, currentTime, prevTime, TimeDelta, TimeElapsed;
Please let me know what is wrong here and how to fix it, or if you have a better way to count fps. Thanks!!!!!!
I am using DirectX 9 btw but I doubt that is relevant, and I am using PeekMessage. Should I be using an if else statement instead? Here is my message processing loop:
MSG msg;
ZeroMemory (&msg, sizeof (MSG));
while (msg.message != WM_QUIT)
{
if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
TranslateMessage (&msg);
DispatchMessage (&msg);
}
Update ();
RenderFrame ();
}
