NAME
SAMPLE - Stores sound data. Allegro game programming library.
SYNOPSIS
#include <allegro.h>
typedef struct SAMPLE
DESCRIPTION
int bits; - 8 or 16
int stereo; - sample type flag
int freq; - sample frequency
int priority; - 0-255
unsigned long len; - length (in samples)
unsigned long loop_start; - loop start position
unsigned long loop_end; - loop finish position
void *data; - raw sample data
A sample structure, which holds sound data, used by the digital sample
routines. You can consider all of these fields as read only except
priority, loop_start and loop_end, which you can change them for
example after loading a sample from disk.
The priority is a value from 0 to 255 (by default set to 128) and
controls how hardware voices on the sound card are allocated if you
attempt to play more than the driver can handle. This may be used to
ensure that the less important sounds are cut off while the important
ones are preserved.
The variables loop_start and loop_end specify the loop position in
sample units, and are set by default to the start and end of the
sample.
If you are creating your own samples on the fly, you might also want to
modify the raw data of the sample pointed by the data field. The sample
data are always in unsigned format. This means that if you are loading
a PCM encoded sound file with signed 16-bit samples, you would have to
XOR every two bytes (i.e. every sample value) with 0x8000 to change the
signedness.
SEE ALSO
load_sample(3alleg), exsample(3alleg)