making timer..

I assume you mean a timer function in C++, like for example timeGetTime() or QueryPerformanceCounter() in the Win32 API.

What do you mean by "it gets slow or fast"? That it constantly lags behind or speeds ahead, or that it returns irregular time values? You really should try to improve your language so that people can understand you better and offer you better help with your problems.

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Staffan Einarsson

sorry for my bad english
ok, can you tell me how can i make a timer?
thank you for your answering

Well if all you want is a function which returns the current time when you call it you should look into timeGetTime()

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/multimed/htm/_win32_timegettime.asp

It returns the number of milliseconds elapsed since the system started.
You'll need to link with winmm.lib for it to work. Also you need to remember to add

timeBeginPeriod(1);

at the beginning of your program and

timeEndPeriod(1);

at the end for the precision to be one millisecond.

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Staffan Einarsson

thank you again :)
and about the another question ?
can you answer me :P

[Edited by - ff8 on January 9, 2005 7:18:38 AM]

You should be able to figure it out yourself, but here you go:

time passed since last update (which could be last frame):
delta_time = current_time - last_time

to check if a second is passed since last fps check (to display fps):
if (current_time - fps_time >= 1000)
update fps counter and set fps to 0

when doing movement or something like that you would do this:
movement = movement_in_a_millisecond * delta_time

or, if you're clever, to make it easy for yourself (remember to make delta_time a float):
delta_time = (current_time - last_time) / 1000
movement = movement_in_a_second * delta_time

For your second question you'll want to use: glReadPixels() and a jpeg library. A few of those links look promissing, or maybe someone here can recomend a good one for you.