Good fps function already written?

Have you looked into fraps? It may be just what you need. It will overlay a fps counter over any directX code. It's a good way to tell the fps for yourself, and not have to write a fps counter, or remove it for others.

the site is http://www.fraps.com ? Thanks, I will try it out. My program is OpenGL but it looks like it has that mode as well.

I just remembered that since I am in a QT glCanvas, I have an upper frame rate limit due to its timers, so I can't even test performance of different things on such a coarse scale. So I will have to do timer functions around the differnt calls that I need to gauge.