mirror of
https://github.com/Oibaf66/frodo-wii.git
synced 2024-11-10 21:55:11 +01:00
149 lines
3.7 KiB
C
149 lines
3.7 KiB
C
/****************************************************************************
|
|
* FCE Ultra 0.98.12
|
|
* Nintendo Wii/Gamecube Port
|
|
*
|
|
* Tantric September 2008
|
|
* eke-eke October 2008
|
|
*
|
|
* gcaudio.c
|
|
*
|
|
* Audio driver
|
|
****************************************************************************/
|
|
|
|
#include <gccore.h>
|
|
#include <string.h>
|
|
|
|
#define SAMPLERATE 32000
|
|
|
|
#define MIXBUFSIZE_BYTES 16000
|
|
#define MIXBUFSIZE_SHORT (MIXBUFSIZE_BYTES / 2)
|
|
#define MIXBUFSIZE_WORDS (MIXBUFSIZE_BYTES / 4)
|
|
|
|
#define SOUNDBUFSIZE 2048
|
|
|
|
static u8 ConfigRequested = 0;
|
|
static u8 soundbuffer[2][SOUNDBUFSIZE] ATTRIBUTE_ALIGN(32);
|
|
static u8 mixbuffer[MIXBUFSIZE_BYTES];
|
|
static int mixhead = 0;
|
|
static int mixtail = 0;
|
|
static int whichab = 0;
|
|
static int IsPlaying = 0;
|
|
|
|
/****************************************************************************
|
|
* MixerCollect
|
|
*
|
|
* Collects sound samples from mixbuffer and puts them into outbuffer
|
|
* Makes sure to align them to 32 bytes for AUDIO_InitDMA
|
|
***************************************************************************/
|
|
static int MixerCollect( u8 *outbuffer, int len )
|
|
{
|
|
u32 *dst = (u32 *)outbuffer;
|
|
u32 *src = (u32 *)mixbuffer;
|
|
int done = 0;
|
|
|
|
// Always clear output buffer
|
|
memset(outbuffer, 0, len);
|
|
|
|
while ( ( mixtail != mixhead ) && ( done < len ) )
|
|
{
|
|
*dst++ = src[mixtail++];
|
|
if (mixtail == MIXBUFSIZE_WORDS) mixtail = 0;
|
|
done += 4;
|
|
}
|
|
|
|
// Realign to 32 bytes for DMA
|
|
mixtail -= ((done&0x1f) >> 2);
|
|
if (mixtail < 0)
|
|
mixtail += MIXBUFSIZE_WORDS;
|
|
done &= ~0x1f;
|
|
|
|
return done;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* AudioSwitchBuffers
|
|
*
|
|
* Manages which buffer is played next
|
|
***************************************************************************/
|
|
static void AudioSwitchBuffers()
|
|
{
|
|
if ( !ConfigRequested )
|
|
{
|
|
int len = MixerCollect( soundbuffer[whichab], SOUNDBUFSIZE );
|
|
if (len == 0)
|
|
return;
|
|
|
|
DCFlushRange(soundbuffer[whichab], len);
|
|
AUDIO_InitDMA((u32)soundbuffer[whichab], len);
|
|
AUDIO_StartDMA();
|
|
whichab ^= 1;
|
|
IsPlaying = 1;
|
|
}
|
|
else IsPlaying = 0;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* InitialiseAudio
|
|
*
|
|
* Initializes sound system on first load of emulator
|
|
***************************************************************************/
|
|
void InitialiseAudio()
|
|
{
|
|
AUDIO_Init(NULL); // Start audio subsystem
|
|
AUDIO_SetDSPSampleRate(AI_SAMPLERATE_32KHZ);
|
|
AUDIO_RegisterDMACallback( AudioSwitchBuffers );
|
|
memset(soundbuffer, 0, SOUNDBUFSIZE*2);
|
|
memset(mixbuffer, 0, MIXBUFSIZE_BYTES);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* StopAudio
|
|
*
|
|
* Pause audio output when returning to menu
|
|
***************************************************************************/
|
|
void StopAudio()
|
|
{
|
|
AUDIO_StopDMA();
|
|
IsPlaying = 0;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* ResetAudio
|
|
*
|
|
* Reset audio output when loading a new game
|
|
***************************************************************************/
|
|
void ResetAudio()
|
|
{
|
|
memset(soundbuffer, 0, SOUNDBUFSIZE*2);
|
|
memset(mixbuffer, 0, MIXBUFSIZE_BYTES);
|
|
mixhead = mixtail = 0;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* PlaySound
|
|
*
|
|
* Puts incoming mono samples into mixbuffer
|
|
* Splits mono samples into two channels (stereo)
|
|
****************************************************************************/
|
|
void PlaySound( int16_t *Buffer, int count )
|
|
{
|
|
u32 *dst = (u32 *)mixbuffer;
|
|
int i;
|
|
|
|
for( i = 0; i < count; i++ )
|
|
{
|
|
u16 sample;
|
|
|
|
sample = (Buffer[i] & 0xffff);
|
|
dst[mixhead++] = sample | ( sample << 16);
|
|
if (mixhead == MIXBUFSIZE_WORDS)
|
|
mixhead = 0;
|
|
}
|
|
|
|
// Restart Sound Processing if stopped
|
|
if (IsPlaying == 0)
|
|
{
|
|
AudioSwitchBuffers ();
|
|
}
|
|
}
|