Fix engine not starting on Windows if linked against SDL > 2.0.5
[xonotic/darkplaces.git] / snd_sdl.c
index 38fb205..21341dc 100644 (file)
--- a/snd_sdl.c
+++ b/snd_sdl.c
@@ -16,74 +16,91 @@ You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
-#include "quakedef.h"
-#include "snd_main.h"
+#include <math.h>
 #include <SDL.h>
 
-/*
-Info:
-One SDL sample consists of x channel samples
-The mixer supposes that the driver has one channel entry/sample though it has x channels/sample
-like the SDL
-*/
-
-#define AUDIO_SDL_SAMPLES              4096
-#define AUDIO_LOCALFACTOR              4
+#include "quakedef.h"
 
-typedef struct AudioState_s
-{
-       int             width;
-    int                size;
-       int             pos;
-       void    *buffer;
-} AudioState;
+#include "snd_main.h"
 
 
-extern mempool_t *snd_mempool;
-static AudioState       as;
+static unsigned int sdlaudiotime = 0;
+static int audio_device = 0;
 
-static void Buffer_Callback(void *userdata, Uint8 *stream, int len);
 
-/*
-==================
-S_BlockSound
-==================
-*/
-void S_BlockSound( void )
+// Note: SDL calls SDL_LockAudio() right before this function, so no need to lock the audio data here
+static void Buffer_Callback (void *userdata, Uint8 *stream, int len)
 {
-       snd_blocked++;
-
-       if( snd_blocked == 1 )
-               SDL_PauseAudio( true );
+       unsigned int factor, RequestedFrames, MaxFrames, FrameCount;
+       unsigned int StartOffset, EndOffset;
+
+       factor = snd_renderbuffer->format.channels * snd_renderbuffer->format.width;
+       if ((unsigned int)len % factor != 0)
+               Sys_Error("SDL sound: invalid buffer length passed to Buffer_Callback (%d bytes)\n", len);
+
+       RequestedFrames = (unsigned int)len / factor;
+
+       if (SndSys_LockRenderBuffer())
+       {
+               if (snd_usethreadedmixing)
+               {
+                       S_MixToBuffer(stream, RequestedFrames);
+                       if (snd_blocked)
+                               memset(stream, snd_renderbuffer->format.width == 1 ? 0x80 : 0, len);
+                       SndSys_UnlockRenderBuffer();
+                       return;
+               }
+
+               // Transfert up to a chunk of samples from snd_renderbuffer to stream
+               MaxFrames = snd_renderbuffer->endframe - snd_renderbuffer->startframe;
+               if (MaxFrames > RequestedFrames)
+                       FrameCount = RequestedFrames;
+               else
+                       FrameCount = MaxFrames;
+               StartOffset = snd_renderbuffer->startframe % snd_renderbuffer->maxframes;
+               EndOffset = (snd_renderbuffer->startframe + FrameCount) % snd_renderbuffer->maxframes;
+               if (StartOffset > EndOffset)  // if the buffer wraps
+               {
+                       unsigned int PartialLength1, PartialLength2;
+
+                       PartialLength1 = (snd_renderbuffer->maxframes - StartOffset) * factor;
+                       memcpy(stream, &snd_renderbuffer->ring[StartOffset * factor], PartialLength1);
+
+                       PartialLength2 = FrameCount * factor - PartialLength1;
+                       memcpy(&stream[PartialLength1], &snd_renderbuffer->ring[0], PartialLength2);
+               }
+               else
+                       memcpy(stream, &snd_renderbuffer->ring[StartOffset * factor], FrameCount * factor);
+
+               snd_renderbuffer->startframe += FrameCount;
+
+               if (FrameCount < RequestedFrames && developer_insane.integer && vid_activewindow)
+                       Con_DPrintf("SDL sound: %u sample frames missing\n", RequestedFrames - FrameCount);
+
+               sdlaudiotime += RequestedFrames;
+
+               SndSys_UnlockRenderBuffer();
+       }
 }
 
 
 /*
-==================
-S_UnblockSound
-==================
+====================
+SndSys_Init
+
+Create "snd_renderbuffer" with the proper sound format if the call is successful
+May return a suggested format if the requested format isn't available
+====================
 */
-void S_UnblockSound( void )
+qboolean SndSys_Init (const snd_format_t* requested, snd_format_t* suggested)
 {
-       snd_blocked--;
-       if( snd_blocked == 0 )
-               SDL_PauseAudio( false );
-}
-
+       unsigned int buffersize;
+       SDL_AudioSpec wantspec;
+       SDL_AudioSpec obtainspec;
 
-/*
-==================
-SNDDMA_Init
+       snd_threaded = false;
 
-Try to find a sound device to mix for.
-Returns false if nothing is found.
-==================
-*/
-
-qboolean SNDDMA_Init(void)
-{
-       SDL_AudioSpec spec;
-       int i;
+       Con_DPrint ("SndSys_Init: using the SDL module\n");
 
        // Init the SDL Audio subsystem
        if( SDL_InitSubSystem( SDL_INIT_AUDIO ) ) {
@@ -91,117 +108,150 @@ qboolean SNDDMA_Init(void)
                return false;
        }
 
-       // Init the shm structure
-       memset( (void*) shm, 0, sizeof(*shm) );
-       
-       shm->format.channels = 2; //stereo
-       shm->format.width = 2;
-
-// COMMANDLINEOPTION: SDL Sound: -sndspeed <hz> chooses 44100 hz, 22100 hz, or 11025 hz sound output rate
-       i = COM_CheckParm( "-sndspeed" );
-       if( i && i != ( com_argc - 1 ) )
-               shm->format.speed = atoi( com_argv[ i+1 ] );
-       else
-               shm->format.speed = 44100;
-
-       shm->samplepos = 0;
-       shm->samples = AUDIO_SDL_SAMPLES * AUDIO_LOCALFACTOR;
-       shm->bufferlength = shm->samples * shm->format.width;
-       shm->buffer = Mem_Alloc( snd_mempool, shm->bufferlength );
-
-       // Init the as structure
-       as.buffer = shm->buffer;
-       as.width = shm->format.width;
-       as.pos = 0;
-       as.size = shm->bufferlength;
+       buffersize = (unsigned int)ceil((double)requested->speed / 25.0); // 2048 bytes on 24kHz to 48kHz
 
        // Init the SDL Audio subsystem
-       spec.callback = Buffer_Callback;
-       spec.channels = shm->format.channels;
-       spec.format = AUDIO_S16SYS;
-       spec.freq = shm->format.speed;
-       spec.userdata = NULL;
-       spec.samples = AUDIO_SDL_SAMPLES; 
-       
-       if( SDL_OpenAudio( &spec, NULL ) ) {
-               Con_Print( "Failed to open the audio device!\n" );
-               Con_DPrintf( 
-                       "Audio Specification:\n"
-                       "\tChannels  : %i\n"
-                       "\tFormat    : %x\n"
-                       "\tFrequency : %i\n"
-                       "\tBuffersize: %i Bytes(%i Samples)\n", 
-                       spec.channels, spec.format, spec.freq, shm->bufferlength , spec.samples );
-               Mem_Free( shm->buffer ); 
+       wantspec.callback = Buffer_Callback;
+       wantspec.userdata = NULL;
+       wantspec.freq = requested->speed;
+       wantspec.format = ((requested->width == 1) ? AUDIO_U8 : AUDIO_S16SYS);
+       wantspec.channels = requested->channels;
+       wantspec.samples = CeilPowerOf2(buffersize);  // needs to be a power of 2 on some platforms.
+
+       Con_Printf("Wanted audio Specification:\n"
+                               "\tChannels  : %i\n"
+                               "\tFormat    : 0x%X\n"
+                               "\tFrequency : %i\n"
+                               "\tSamples   : %i\n",
+                               wantspec.channels, wantspec.format, wantspec.freq, wantspec.samples);
+
+       if ((audio_device = SDL_OpenAudioDevice(NULL, 0, &wantspec, &obtainspec, 0)) == 0)
+       {
+               Con_Printf( "Failed to open the audio device! (%s)\n", SDL_GetError() );
+               return false;
+       }
+
+       Con_Printf("Obtained audio specification:\n"
+                               "\tChannels  : %i\n"
+                               "\tFormat    : 0x%X\n"
+                               "\tFrequency : %i\n"
+                               "\tSamples   : %i\n",
+                               obtainspec.channels, obtainspec.format, obtainspec.freq, obtainspec.samples);
+
+       // If we haven't obtained what we wanted
+       if (wantspec.freq != obtainspec.freq ||
+               wantspec.format != obtainspec.format ||
+               wantspec.channels != obtainspec.channels)
+       {
+               SDL_CloseAudioDevice(audio_device);
+
+               // Pass the obtained format as a suggested format
+               if (suggested != NULL)
+               {
+                       suggested->speed = obtainspec.freq;
+                       // FIXME: check the format more carefully. There are plenty of unsupported cases
+                       suggested->width = ((obtainspec.format == AUDIO_U8) ? 1 : 2);
+                       suggested->channels = obtainspec.channels;
+               }
+
                return false;
        }
 
-       SDL_PauseAudio( false );
+       snd_threaded = true;
+
+       snd_renderbuffer = Snd_CreateRingBuffer(requested, 0, NULL);
+       if (snd_channellayout.integer == SND_CHANNELLAYOUT_AUTO)
+               Cvar_SetValueQuick (&snd_channellayout, SND_CHANNELLAYOUT_STANDARD);
+
+       sdlaudiotime = 0;
+       SDL_PauseAudioDevice(audio_device, 0);
 
        return true;
 }
 
+
 /*
-==============
-SNDDMA_GetDMAPos
+====================
+SndSys_Shutdown
 
-return the current sample position (in mono samples read)
-inside the recirculating dma buffer, so the mixing code will know
-how many sample are required to fill it up.
-===============
+Stop the sound card, delete "snd_renderbuffer" and free its other resources
+====================
 */
-int SNDDMA_GetDMAPos(void)
+void SndSys_Shutdown(void)
 {
-       shm->samplepos = (as.pos / as.width) % shm->samples;
-       return shm->samplepos;
+       if (audio_device > 0) {
+               SDL_CloseAudioDevice(audio_device);
+               audio_device = 0;
+       }
+       if (snd_renderbuffer != NULL)
+       {
+               Mem_Free(snd_renderbuffer->ring);
+               Mem_Free(snd_renderbuffer);
+               snd_renderbuffer = NULL;
+       }
 }
 
+
 /*
-==============
-SNDDMA_Submit
+====================
+SndSys_Submit
 
-Send sound to device if buffer isn't really the dma buffer
-===============
+Submit the contents of "snd_renderbuffer" to the sound card
+====================
 */
-void SNDDMA_Submit(void)
+void SndSys_Submit (void)
 {
-
+       // Nothing to do here (this sound module is callback-based)
 }
 
+
 /*
-==============
-SNDDMA_Shutdown
+====================
+SndSys_GetSoundTime
 
-Reset the sound device for exiting
-===============
+Returns the number of sample frames consumed since the sound started
+====================
 */
-void SNDDMA_Shutdown(void)
+unsigned int SndSys_GetSoundTime (void)
 {
-       SDL_CloseAudio();
-       Mem_Free( as.buffer );
+       return sdlaudiotime;
 }
 
-void *S_LockBuffer(void)
+
+/*
+====================
+SndSys_LockRenderBuffer
+
+Get the exclusive lock on "snd_renderbuffer"
+====================
+*/
+qboolean SndSys_LockRenderBuffer (void)
 {
-       SDL_LockAudio();
-       return shm->buffer;
+       SDL_LockAudioDevice(audio_device);
+       return true;
 }
 
-void S_UnlockBuffer(void)
+
+/*
+====================
+SndSys_UnlockRenderBuffer
+
+Release the exclusive lock on "snd_renderbuffer"
+====================
+*/
+void SndSys_UnlockRenderBuffer (void)
 {
-       SDL_UnlockAudio();
+       SDL_UnlockAudioDevice(audio_device);
 }
 
-static void Buffer_Callback(void *userdata, Uint8 *stream, int len)
+/*
+====================
+SndSys_SendKeyEvents
+
+Send keyboard events originating from the sound system (e.g. MIDI)
+====================
+*/
+void SndSys_SendKeyEvents(void)
 {
-       if( len > as.size )
-               len = as.size;
-       if( len > as.size - as.pos ) {
-               memcpy( stream, (Uint8*) as.buffer + as.pos, as.size - as.pos );
-               len -= as.size - as.pos;
-               as.pos = 0;
-       }
-       memcpy( stream, (Uint8*) as.buffer + as.pos, len );
-       as.pos = (as.pos + len) % as.size;
+       // not supported
 }
-