I am working on a tile based side scroller, and when I set the screen to scroll at 200 pixels/sec it is smoother when I lock the fps to about 45 or so, but when I do not lock the fps it gets choppy unless I run the screen at about 300 pixels/sec. what gives here? can anyone help with this.

I dont now why changing the speed of the scrolling would make it less choppy, but I do know if it runs faster than the moniter Refresh Rate, is will be choppy. You could use VSynce if you wanted to.

Yup If you run faster than the refresh rate OR I think an Irrational FPS is also choppy, for example if the monitors refresh rate is 60, then good fps to stick to are one that will allow every update to fall right on a refresh so 30 would look really good too (Every second refresh), probably your second best, but also any other multiples where every frame lands on an update. so there are some odd ones, maybe 45 is one of them?

Anyhow, best thing to do is use VSync and have an option in your program to turn it off or on, also you should have an option to slow the frame rate for laptops and other LCDs and such. But generally stick to VSync and it''s all good. If someone want incredable performance on there computer then they''ll probably have a monitor with 75 or 90 or 120hz refresh. But for normal people 60fps is perfect!

- Ben

60fps = OK
60Hz = instant headache.

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