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/***************************************************************************
Poly-Play
(c) 1985 by VEB Polytechnik Karl-Marx-Stadt
sound hardware
driver written by Martin Buchholz (buchholz@mail.uni-greifswald.de)
***************************************************************************/
#include "driver.h"
#include <math.h>
#include "sound/samples.h"
#define LFO_VOLUME 25
#define SAMPLE_LENGTH 32
#define SAMPLE_AMPLITUDE 0x4000
static int freq1, freq2, channel_playing1, channel_playing2;
static INT16 backgroundwave[SAMPLE_LENGTH];
void polyplay_sh_start(void)
{
int i;
for (i = 0; i < SAMPLE_LENGTH / 2; i++) {
backgroundwave[i] = + SAMPLE_AMPLITUDE;
}
for (i = SAMPLE_LENGTH / 2; i < SAMPLE_LENGTH; i++) {
backgroundwave[i] = - SAMPLE_AMPLITUDE;
}
freq1 = freq2 = 110;
channel_playing1 = 0;
channel_playing2 = 0;
}
void polyplay_set_channel1(int active)
{
channel_playing1 = active;
}
void polyplay_set_channel2(int active)
{
channel_playing2 = active;
}
void polyplay_play_channel1(int data)
{
if (data) {
freq1 = 2457600 / 16 / data / 8;
sample_set_volume(0, channel_playing1 * 1.0);
sample_start_raw(0, backgroundwave, sizeof(backgroundwave)/2, sizeof(backgroundwave)*freq1,1);
}
else {
sample_stop(0);
sample_stop(1);
}
}
void polyplay_play_channel2(int data)
{
if (data) {
freq2 = 2457600 / 16 / data / 8;
sample_set_volume(1, channel_playing2 * 1.0);
sample_start_raw(1, backgroundwave, sizeof(backgroundwave)/2, sizeof(backgroundwave)*freq2,1);
}
else {
sample_stop(0);
sample_stop(1);
}
}
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