- 1 year ago
Do I have to call timeBeginPeriod before timeSetEvent when using Windows multimedia timers?
Yes, it is recommended to call timeBeginPeriod
before timeSetEvent
when using Windows multimedia timers to ensure accurate timing.
The timeBeginPeriod
function sets the resolution of the system timer, which affects the precision of the multimedia timers. By default, the system timer resolution is set to around 15.6 milliseconds, which may not provide sufficient accuracy for certain timing requirements.
To improve the accuracy of multimedia timers, you can call timeBeginPeriod
with a smaller period value (in milliseconds) before using timeSetEvent
. This function requests a higher timer resolution from the system.
Here's an example of how you can use timeBeginPeriod
and timeSetEvent
together:
cpp#include <Windows.h>
#include <mmsystem.h>
#pragma comment(lib, "winmm.lib")
void CALLBACK TimerCallback(UINT uTimerID, UINT uMsg, DWORD_PTR dwUser, DWORD_PTR dw1, DWORD_PTR dw2)
{
// Timer callback function
}
int main()
{
// Set the timer resolution to 1 millisecond
timeBeginPeriod(1);
// Set up the multimedia timer
UINT timerID = timeSetEvent(10, 0, TimerCallback, 0, TIME_PERIODIC);
// ...
// Stop the multimedia timer
timeKillEvent(timerID);
// Reset the timer resolution to the default
timeEndPeriod(1);
return 0;
}
In this example, timeBeginPeriod(1)
is called to set the timer resolution to 1 millisecond before using timeSetEvent
to create a multimedia timer with a period of 10 milliseconds. After the timer is no longer needed, timeKillEvent
is used to stop the timer, and timeEndPeriod(1)
is called to reset the timer resolution to the default value.
By calling timeBeginPeriod
before timeSetEvent
and timeEndPeriod
after timeKillEvent
, you can ensure that the multimedia timer operates with the desired resolution and accuracy. Remember to link against the winmm.lib
library by adding #pragma comment(lib, "winmm.lib")
to your code.