simgear/example/example.cxx
1998-07-16 17:48:11 +00:00

90 lines
2.1 KiB
C++

#include "sl.h"
#include "sm.h"
#include <math.h>
/*
Construct a sound scheduler and a mixer.
*/
slScheduler sched ( 8000 ) ;
smMixer mixer ;
int main ()
{
mixer . setMasterVolume ( 30 ) ;
sched . setSafetyMargin ( 0.128 ) ;
/* Just for fun, let's make a one second synthetic engine sample... */
Uchar buffer [ 8000 ] ;
for ( int i = 0 ; i < 8000 ; i++ )
{
/* Sum some sin waves and convert to range 0..1 */
float level = ( sin ( (double) i * 2.0 * M_PI / (8000.0/ 50.0) ) +
sin ( (double) i * 2.0 * M_PI / (8000.0/149.0) ) +
sin ( (double) i * 2.0 * M_PI / (8000.0/152.0) ) +
sin ( (double) i * 2.0 * M_PI / (8000.0/192.0) )
) / 8.0f + 0.5f ;
/* Convert to unsigned byte */
buffer [ i ] = (Uchar) ( level * 255.0 ) ;
}
/* Set up four samples and a loop */
slSample *s = new slSample ( buffer, 8000 ) ;
slSample *s1 = new slSample ( "scream.ub", & sched ) ;
slSample *s2 = new slSample ( "zzap.wav" , & sched ) ;
slSample *s3 = new slSample ( "cuckoo.au", & sched ) ;
slSample *s4 = new slSample ( "wheeee.ub", & sched ) ;
/* Mess about with some of the samples... */
s1 -> adjustVolume ( 2.2 ) ;
s2 -> adjustVolume ( 0.5 ) ;
s3 -> adjustVolume ( 0.2 ) ;
/* Play the engine sample continuously. */
sched . loopSample ( s ) ;
int tim = 0 ; /* My periodic event timer. */
while ( SL_TRUE )
{
tim++ ; /* Time passes */
if ( tim % 200 == 0 ) sched.playSample ( s1 ) ;
if ( tim % 180 == 0 ) sched.playSample ( s2 ) ;
if ( tim % 150 == 0 ) sched.playSample ( s3 ) ;
if ( tim % 120 == 0 ) sched.playSample ( s4 ) ;
/*
For the sake of realism, I'll delay for 1/30th second to
simulate a graphics update process.
*/
#ifdef WIN32
Sleep ( 1000 / 30 ) ; /* 30Hz */
#elif defined(sgi)
sginap( 3 ); /* ARG */
#else
usleep ( 1000000 / 30 ) ; /* 30Hz */
#endif
/*
This would normally be called just before the graphics buffer swap
- but it could be anywhere where it's guaranteed to get called
fairly often.
*/
sched . update () ;
}
}