Fix high pitch noise in SDL

This commit is contained in:
Miloslav Číž 2020-10-01 14:10:43 +02:00
parent a91092401d
commit 6f78cc0338
1 changed files with 7 additions and 9 deletions

View File

@ -33,8 +33,8 @@
#define SFG_REVEAL_MAP 1
// #define SFG_INFINITE_AMMO 1
#define SFG_SCREEN_RESOLUTION_X 88
#define SFG_SCREEN_RESOLUTION_Y 110
// #define SFG_SCREEN_RESOLUTION_X 88
// #define SFG_SCREEN_RESOLUTION_Y 110
// #define SFG_SCREEN_RESOLUTION_X 80
// #define SFG_SCREEN_RESOLUTION_Y 64
@ -294,14 +294,12 @@ typedef void (*em_callback_func)(void);
void emscripten_set_main_loop(em_callback_func func, int fps, int simulate_infinite_loop);
#endif
#define AUDIO_ZERO 32768
uint16_t audioBuff[SFG_SFX_SAMPLE_COUNT];
uint16_t audioPos = 0;
static inline uint16_t mixSamples(uint16_t sample1, uint16_t sample2)
{
return (sample1 >> 1) + (sample2 >> 1);
return (sample1 + sample2) >> 1; //(sample1 >> 1) + (sample2 >> 1);
}
uint8_t musicOn = 1;
@ -316,7 +314,7 @@ void audioFillCallback(void *userdata, uint8_t *s, int l)
mixSamples(audioBuff[audioPos],SFG_getNextMusicSample() << MUSIC_VOLUME) :
audioBuff[audioPos];
audioBuff[audioPos] = AUDIO_ZERO;
audioBuff[audioPos] = 0;
audioPos = (audioPos < SFG_SFX_SAMPLE_COUNT - 1) ? (audioPos + 1) : 0;
}
}
@ -330,7 +328,7 @@ void SFG_playSound(uint8_t soundIndex, uint8_t volume)
{
uint16_t pos = audioPos;
uint8_t volumeShift = 15 - volume / 16;
uint16_t baseLevel = AUDIO_ZERO - (0x8000 >> volumeShift);
uint16_t baseLevel = -1 * (0x8000 >> volumeShift);
for (int i = 0; i < SFG_SFX_SAMPLE_COUNT; ++i)
{
@ -421,7 +419,7 @@ int main(int argc, char *argv[])
SDL_memset(&audioSpec, 0, sizeof(audioSpec));
audioSpec.callback = audioFillCallback;
audioSpec.freq = 8000;
audioSpec.format = AUDIO_U16;
audioSpec.format = AUDIO_S16;
audioSpec.channels = 1;
#ifdef __EMSCRIPTEN__
audioSpec.samples = 1024;
@ -433,7 +431,7 @@ int main(int argc, char *argv[])
puts("SDL: could not initialize audio");
for (int16_t i = 0; i < SFG_SFX_SAMPLE_COUNT; ++i)
audioBuff[i] = AUDIO_ZERO;
audioBuff[i] = 0;
SDL_PauseAudio(0);