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Best way to sync frames in SW 2D rendering?

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Hi,

I'm currently using TinyPTC in GDI mode (yeah I know, outdated and stuff) to be able to use a backbuffer and flip it to the GDI surface, it's pretty neat for doing simple 2D rendering the old pixel-fashioned way.
I want to flip the buffer every frame, being 60Hz, how can I do this in a very timing-precise way?

Currently I use a very slow and unaccurate jittering way like this:
 unsigned int buffer[WIDTH * HEIGHT]; static int next_tick = 0; static int tick_interval = (int)(1.0f * 1000.0f / 60.0f); void syncframe(void) { if (next_tick >= timeGetTime()) { Sleep(next_tick - timeGetTime()); } next_tick = timeGetTime() + tick_interval; } int main() { while (running) { /* clear buffer */ /* run functions that plot pixels to buffer */ /* flip buffer and sync frame */ ptc_update(buffer); syncframe(); } } 
It sure does work, but it lags rhythmically. I know there's no way to get 100% fullspeed on a multitask system, because there are several low-level threads in use by the OS....
But there should at least be a way to get 60Hz smooth, 60Hz is not extremely fast - would triple buffering help? Any known tricks and tips to get this working in a simple way? As said, this is simple software 2D stuff.

Any help appreciated!

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Unfotunately GDI and the win32 APIs don't expose the vsync signal.

Basically you do what you're doing now, more or less. You can probably smooth things out a bit more by sleeping for your current amount, less 5ms (the timer (or sleep) is only guaranteed accurate to 5ms increments, IIRC)... then busy-wait for the last <5ms. This may or may not actually prove better.

In my own renderer I do basically this, IIRC, and framerate is locked pretty tight on 60fps, with an occasional flash into 59fps reported.

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