aboutsummaryrefslogtreecommitdiffstats
path: root/src/media/UAudioPlayback_SoftMixer.pas
diff options
context:
space:
mode:
Diffstat (limited to 'src/media/UAudioPlayback_SoftMixer.pas')
-rw-r--r--src/media/UAudioPlayback_SoftMixer.pas1132
1 files changed, 1132 insertions, 0 deletions
diff --git a/src/media/UAudioPlayback_SoftMixer.pas b/src/media/UAudioPlayback_SoftMixer.pas
new file mode 100644
index 00000000..6ddae980
--- /dev/null
+++ b/src/media/UAudioPlayback_SoftMixer.pas
@@ -0,0 +1,1132 @@
+unit UAudioPlayback_SoftMixer;
+
+interface
+
+{$IFDEF FPC}
+ {$MODE Delphi}
+{$ENDIF}
+
+{$I switches.inc}
+
+
+uses
+ Classes,
+ SysUtils,
+ sdl,
+ URingBuffer,
+ UMusic,
+ UAudioPlaybackBase;
+
+type
+ TAudioPlayback_SoftMixer = class;
+
+ TGenericPlaybackStream = class(TAudioPlaybackStream)
+ private
+ Engine: TAudioPlayback_SoftMixer;
+
+ SampleBuffer: PChar;
+ SampleBufferSize: integer;
+ SampleBufferCount: integer; // number of available bytes in SampleBuffer
+ SampleBufferPos: cardinal;
+
+ SourceBuffer: PChar;
+ SourceBufferSize: integer;
+ SourceBufferCount: integer; // number of available bytes in SourceBuffer
+
+ Converter: TAudioConverter;
+ Status: TStreamStatus;
+ InternalLock: PSDL_Mutex;
+ SoundEffects: TList;
+ fVolume: single;
+
+ FadeInStartTime, FadeInTime: cardinal;
+ FadeInStartVolume, FadeInTargetVolume: single;
+
+ NeedsRewind: boolean;
+
+ procedure Reset();
+
+ procedure ApplySoundEffects(Buffer: PChar; BufferSize: integer);
+ function InitFormatConversion(): boolean;
+ procedure FlushBuffers();
+
+ procedure LockSampleBuffer(); {$IFDEF HasInline}inline;{$ENDIF}
+ procedure UnlockSampleBuffer(); {$IFDEF HasInline}inline;{$ENDIF}
+ protected
+ function GetLatency(): double; override;
+ function GetStatus(): TStreamStatus; override;
+ function GetVolume(): single; override;
+ procedure SetVolume(Volume: single); override;
+ function GetLength(): real; override;
+ function GetLoop(): boolean; override;
+ procedure SetLoop(Enabled: boolean); override;
+ function GetPosition: real; override;
+ procedure SetPosition(Time: real); override;
+ public
+ constructor Create(Engine: TAudioPlayback_SoftMixer);
+ destructor Destroy(); override;
+
+ function Open(SourceStream: TAudioSourceStream): boolean; override;
+ procedure Close(); override;
+
+ procedure Play(); override;
+ procedure Pause(); override;
+ procedure Stop(); override;
+ procedure FadeIn(Time: real; TargetVolume: single); override;
+
+ function GetAudioFormatInfo(): TAudioFormatInfo; override;
+
+ function ReadData(Buffer: PChar; BufferSize: integer): integer;
+
+ function GetPCMData(var Data: TPCMData): Cardinal; override;
+ procedure GetFFTData(var Data: TFFTData); override;
+
+ procedure AddSoundEffect(Effect: TSoundEffect); override;
+ procedure RemoveSoundEffect(Effect: TSoundEffect); override;
+ end;
+
+ TAudioMixerStream = class
+ private
+ Engine: TAudioPlayback_SoftMixer;
+
+ ActiveStreams: TList;
+ MixerBuffer: PChar;
+ InternalLock: PSDL_Mutex;
+
+ AppVolume: single;
+
+ procedure Lock(); {$IFDEF HasInline}inline;{$ENDIF}
+ procedure Unlock(); {$IFDEF HasInline}inline;{$ENDIF}
+
+ function GetVolume(): single;
+ procedure SetVolume(Volume: single);
+ public
+ constructor Create(Engine: TAudioPlayback_SoftMixer);
+ destructor Destroy(); override;
+ procedure AddStream(Stream: TAudioPlaybackStream);
+ procedure RemoveStream(Stream: TAudioPlaybackStream);
+ function ReadData(Buffer: PChar; BufferSize: integer): integer;
+
+ property Volume: single read GetVolume write SetVolume;
+ end;
+
+ TAudioPlayback_SoftMixer = class(TAudioPlaybackBase)
+ private
+ MixerStream: TAudioMixerStream;
+ protected
+ FormatInfo: TAudioFormatInfo;
+
+ function InitializeAudioPlaybackEngine(): boolean; virtual; abstract;
+ function StartAudioPlaybackEngine(): boolean; virtual; abstract;
+ procedure StopAudioPlaybackEngine(); virtual; abstract;
+ function FinalizeAudioPlaybackEngine(): boolean; virtual; abstract;
+ procedure AudioCallback(Buffer: PChar; Size: integer); {$IFDEF HasInline}inline;{$ENDIF}
+
+ function CreatePlaybackStream(): TAudioPlaybackStream; override;
+ public
+ function GetName: String; override; abstract;
+ function InitializePlayback(): boolean; override;
+ function FinalizePlayback: boolean; override;
+
+ procedure SetAppVolume(Volume: single); override;
+
+ function CreateVoiceStream(ChannelMap: integer; FormatInfo: TAudioFormatInfo): TAudioVoiceStream; override;
+
+ function GetMixer(): TAudioMixerStream; {$IFDEF HasInline}inline;{$ENDIF}
+ function GetAudioFormatInfo(): TAudioFormatInfo;
+
+ procedure MixBuffers(DstBuffer, SrcBuffer: PChar; Size: Cardinal; Volume: Single); virtual;
+ end;
+
+type
+ TGenericVoiceStream = class(TAudioVoiceStream)
+ private
+ VoiceBuffer: TRingBuffer;
+ BufferLock: PSDL_Mutex;
+ PlaybackStream: TGenericPlaybackStream;
+ Engine: TAudioPlayback_SoftMixer;
+ public
+ constructor Create(Engine: TAudioPlayback_SoftMixer);
+
+ function Open(ChannelMap: integer; FormatInfo: TAudioFormatInfo): boolean; override;
+ procedure Close(); override;
+ procedure WriteData(Buffer: PChar; BufferSize: integer); override;
+ function ReadData(Buffer: PChar; BufferSize: integer): integer; override;
+ function IsEOF(): boolean; override;
+ function IsError(): boolean; override;
+ end;
+
+const
+ SOURCE_BUFFER_FRAMES = 4096;
+
+const
+ MAX_VOICE_DELAY = 0.500; // 20ms
+
+implementation
+
+uses
+ Math,
+ ULog,
+ UIni,
+ UFFT,
+ UAudioConverter,
+ UMain;
+
+{ TAudioMixerStream }
+
+constructor TAudioMixerStream.Create(Engine: TAudioPlayback_SoftMixer);
+begin
+ inherited Create();
+
+ Self.Engine := Engine;
+
+ ActiveStreams := TList.Create;
+ InternalLock := SDL_CreateMutex();
+ AppVolume := 1.0;
+end;
+
+destructor TAudioMixerStream.Destroy();
+begin
+ if assigned(MixerBuffer) then
+ Freemem(MixerBuffer);
+ ActiveStreams.Free;
+ SDL_DestroyMutex(InternalLock);
+ inherited;
+end;
+
+procedure TAudioMixerStream.Lock();
+begin
+ SDL_mutexP(InternalLock);
+end;
+
+procedure TAudioMixerStream.Unlock();
+begin
+ SDL_mutexV(InternalLock);
+end;
+
+function TAudioMixerStream.GetVolume(): single;
+begin
+ Lock();
+ Result := AppVolume;
+ Unlock();
+end;
+
+procedure TAudioMixerStream.SetVolume(Volume: single);
+begin
+ Lock();
+ AppVolume := Volume;
+ Unlock();
+end;
+
+procedure TAudioMixerStream.AddStream(Stream: TAudioPlaybackStream);
+begin
+ if not assigned(Stream) then
+ Exit;
+
+ Lock();
+ // check if stream is already in list to avoid duplicates
+ if (ActiveStreams.IndexOf(Pointer(Stream)) = -1) then
+ ActiveStreams.Add(Pointer(Stream));
+ Unlock();
+end;
+
+(*
+ * Sets the entry of stream in the ActiveStreams-List to nil
+ * but does not remove it from the list (Count is not changed!).
+ * Otherwise iterations over the elements might fail due to a
+ * changed Count-property.
+ * Call ActiveStreams.Pack() to remove the nil-pointers
+ * or check for nil-pointers when accessing ActiveStreams.
+ *)
+procedure TAudioMixerStream.RemoveStream(Stream: TAudioPlaybackStream);
+var
+ Index: integer;
+begin
+ Lock();
+ Index := activeStreams.IndexOf(Pointer(Stream));
+ if (Index <> -1) then
+ begin
+ // remove entry but do not decrease count-property
+ ActiveStreams[Index] := nil;
+ end;
+ Unlock();
+end;
+
+function TAudioMixerStream.ReadData(Buffer: PChar; BufferSize: integer): integer;
+var
+ i: integer;
+ Size: integer;
+ Stream: TGenericPlaybackStream;
+ NeedsPacking: boolean;
+begin
+ Result := BufferSize;
+
+ // zero target-buffer (silence)
+ FillChar(Buffer^, BufferSize, 0);
+
+ // resize mixer-buffer if necessary
+ ReallocMem(MixerBuffer, BufferSize);
+ if not assigned(MixerBuffer) then
+ Exit;
+
+ Lock();
+
+ NeedsPacking := false;
+
+ // mix streams to one stream
+ for i := 0 to ActiveStreams.Count-1 do
+ begin
+ if (ActiveStreams[i] = nil) then
+ begin
+ NeedsPacking := true;
+ continue;
+ end;
+
+ Stream := TGenericPlaybackStream(ActiveStreams[i]);
+ // fetch data from current stream
+ Size := Stream.ReadData(MixerBuffer, BufferSize);
+ if (Size > 0) then
+ begin
+ // mix stream-data with mixer-buffer
+ // Note: use Self.appVolume instead of Self.Volume to prevent recursive locking
+ Engine.MixBuffers(Buffer, MixerBuffer, Size, AppVolume * Stream.Volume);
+ end;
+ end;
+
+ // remove nil-pointers from list
+ if (NeedsPacking) then
+ begin
+ ActiveStreams.Pack();
+ end;
+
+ Unlock();
+end;
+
+
+{ TGenericPlaybackStream }
+
+constructor TGenericPlaybackStream.Create(Engine: TAudioPlayback_SoftMixer);
+begin
+ inherited Create();
+ Self.Engine := Engine;
+ InternalLock := SDL_CreateMutex();
+ SoundEffects := TList.Create;
+ Status := ssStopped;
+ Reset();
+end;
+
+destructor TGenericPlaybackStream.Destroy();
+begin
+ Close();
+ SDL_DestroyMutex(InternalLock);
+ FreeAndNil(SoundEffects);
+ inherited;
+end;
+
+procedure TGenericPlaybackStream.Reset();
+begin
+ SourceStream := nil;
+
+ FreeAndNil(Converter);
+
+ FreeMem(SampleBuffer);
+ SampleBuffer := nil;
+ SampleBufferPos := 0;
+ SampleBufferSize := 0;
+ SampleBufferCount := 0;
+
+ FreeMem(SourceBuffer);
+ SourceBuffer := nil;
+ SourceBufferSize := 0;
+ SourceBufferCount := 0;
+
+ NeedsRewind := false;
+
+ fVolume := 0;
+ SoundEffects.Clear;
+ FadeInTime := 0;
+end;
+
+function TGenericPlaybackStream.Open(SourceStream: TAudioSourceStream): boolean;
+begin
+ Result := false;
+
+ Close();
+
+ if (not assigned(SourceStream)) then
+ Exit;
+ Self.SourceStream := SourceStream;
+
+ if (not InitFormatConversion()) then
+ begin
+ // reset decode-stream so it will not be freed on destruction
+ Self.SourceStream := nil;
+ Exit;
+ end;
+
+ SourceBufferSize := SOURCE_BUFFER_FRAMES * SourceStream.GetAudioFormatInfo().FrameSize;
+ GetMem(SourceBuffer, SourceBufferSize);
+ fVolume := 1.0;
+
+ Result := true;
+end;
+
+procedure TGenericPlaybackStream.Close();
+begin
+ // stop audio-callback on this stream
+ Stop();
+
+ // Note: PerformOnClose must be called before SourceStream is invalidated
+ PerformOnClose();
+ // and free data
+ Reset();
+end;
+
+procedure TGenericPlaybackStream.LockSampleBuffer();
+begin
+ SDL_mutexP(InternalLock);
+end;
+
+procedure TGenericPlaybackStream.UnlockSampleBuffer();
+begin
+ SDL_mutexV(InternalLock);
+end;
+
+function TGenericPlaybackStream.InitFormatConversion(): boolean;
+var
+ SrcFormatInfo: TAudioFormatInfo;
+ DstFormatInfo: TAudioFormatInfo;
+begin
+ Result := false;
+
+ SrcFormatInfo := SourceStream.GetAudioFormatInfo();
+ DstFormatInfo := GetAudioFormatInfo();
+
+ // TODO: selection should not be done here, use a factory (TAudioConverterFactory) instead
+ {$IF Defined(UseFFmpegResample)}
+ Converter := TAudioConverter_FFmpeg.Create();
+ {$ELSEIF Defined(UseSRCResample)}
+ Converter := TAudioConverter_SRC.Create();
+ {$ELSE}
+ Converter := TAudioConverter_SDL.Create();
+ {$IFEND}
+
+ Result := Converter.Init(SrcFormatInfo, DstFormatInfo);
+end;
+
+procedure TGenericPlaybackStream.Play();
+var
+ Mixer: TAudioMixerStream;
+begin
+ // only paused streams are not flushed
+ if (Status = ssPaused) then
+ NeedsRewind := false;
+
+ // rewind if necessary. Cases that require no rewind are:
+ // - stream was created and never played
+ // - stream was paused and is resumed now
+ // - stream was stopped and set to a new position already
+ if (NeedsRewind) then
+ SetPosition(0);
+
+ // update status
+ Status := ssPlaying;
+
+ NeedsRewind := true;
+
+ // add this stream to the mixer
+ Mixer := Engine.GetMixer();
+ if (Mixer <> nil) then
+ Mixer.AddStream(Self);
+end;
+
+procedure TGenericPlaybackStream.FadeIn(Time: real; TargetVolume: single);
+begin
+ FadeInTime := Trunc(Time * 1000);
+ FadeInStartTime := SDL_GetTicks();
+ FadeInStartVolume := fVolume;
+ FadeInTargetVolume := TargetVolume;
+ Play();
+end;
+
+procedure TGenericPlaybackStream.Pause();
+var
+ Mixer: TAudioMixerStream;
+begin
+ if (Status <> ssPlaying) then
+ Exit;
+
+ Status := ssPaused;
+
+ Mixer := Engine.GetMixer();
+ if (Mixer <> nil) then
+ Mixer.RemoveStream(Self);
+end;
+
+procedure TGenericPlaybackStream.Stop();
+var
+ Mixer: TAudioMixerStream;
+begin
+ if (Status = ssStopped) then
+ Exit;
+
+ Status := ssStopped;
+
+ Mixer := Engine.GetMixer();
+ if (Mixer <> nil) then
+ Mixer.RemoveStream(Self);
+end;
+
+function TGenericPlaybackStream.GetLoop(): boolean;
+begin
+ if assigned(SourceStream) then
+ Result := SourceStream.Loop
+ else
+ Result := false;
+end;
+
+procedure TGenericPlaybackStream.SetLoop(Enabled: boolean);
+begin
+ if assigned(SourceStream) then
+ SourceStream.Loop := Enabled;
+end;
+
+function TGenericPlaybackStream.GetLength(): real;
+begin
+ if assigned(SourceStream) then
+ Result := SourceStream.Length
+ else
+ Result := -1;
+end;
+
+function TGenericPlaybackStream.GetLatency(): double;
+begin
+ Result := Engine.GetLatency();
+end;
+
+function TGenericPlaybackStream.GetStatus(): TStreamStatus;
+begin
+ Result := Status;
+end;
+
+function TGenericPlaybackStream.GetAudioFormatInfo(): TAudioFormatInfo;
+begin
+ Result := Engine.GetAudioFormatInfo();
+end;
+
+procedure TGenericPlaybackStream.FlushBuffers();
+begin
+ SampleBufferCount := 0;
+ SampleBufferPos := 0;
+ SourceBufferCount := 0;
+end;
+
+procedure TGenericPlaybackStream.ApplySoundEffects(Buffer: PChar; BufferSize: integer);
+var
+ i: integer;
+begin
+ for i := 0 to SoundEffects.Count-1 do
+ begin
+ if (SoundEffects[i] <> nil) then
+ begin
+ TSoundEffect(SoundEffects[i]).Callback(Buffer, BufferSize);
+ end;
+ end;
+end;
+
+function TGenericPlaybackStream.ReadData(Buffer: PChar; BufferSize: integer): integer;
+var
+ ConversionInputCount: integer;
+ ConversionOutputSize: integer; // max. number of converted data (= buffer size)
+ ConversionOutputCount: integer; // actual number of converted data
+ SourceSize: integer;
+ RequestedSourceSize: integer;
+ NeededSampleBufferSize: integer;
+ BytesNeeded, BytesAvail: integer;
+ SourceFormatInfo, OutputFormatInfo: TAudioFormatInfo;
+ SourceFrameSize, OutputFrameSize: integer;
+ SkipOutputCount: integer; // number of output-data bytes to skip
+ SkipSourceCount: integer; // number of source-data bytes to skip
+ FillCount: integer; // number of bytes to fill with padding data
+ CopyCount: integer;
+ PadFrame: PChar;
+ i: integer;
+begin
+ Result := -1;
+
+ // sanity check for the source-stream
+ if (not assigned(SourceStream)) then
+ Exit;
+
+ SkipOutputCount := 0;
+ SkipSourceCount := 0;
+ FillCount := 0;
+
+ SourceFormatInfo := SourceStream.GetAudioFormatInfo();
+ SourceFrameSize := SourceFormatInfo.FrameSize;
+ OutputFormatInfo := GetAudioFormatInfo();
+ OutputFrameSize := OutputFormatInfo.FrameSize;
+
+ // synchronize (adjust buffer size)
+ BytesNeeded := Synchronize(BufferSize, OutputFormatInfo);
+ if (BytesNeeded > BufferSize) then
+ begin
+ SkipOutputCount := BytesNeeded - BufferSize;
+ BytesNeeded := BufferSize;
+ end
+ else if (BytesNeeded < BufferSize) then
+ begin
+ FillCount := BufferSize - BytesNeeded;
+ end;
+
+ // lock access to sample-buffer
+ LockSampleBuffer();
+ try
+
+ // skip sample-buffer data
+ SampleBufferPos := SampleBufferPos + SkipOutputCount;
+ // size of available bytes in SampleBuffer after skipping
+ SampleBufferCount := SampleBufferCount - SampleBufferPos;
+ // update byte skip-count
+ SkipOutputCount := -SampleBufferCount;
+
+ // now that we skipped all buffered data from the last pass, we have to skip
+ // data directly after fetching it from the source-stream.
+ if (SkipOutputCount > 0) then
+ begin
+ SampleBufferCount := 0;
+ // convert skip-count to source-format units and resize to a multiple of
+ // the source frame-size.
+ SkipSourceCount := Round((SkipOutputCount * OutputFormatInfo.GetRatio(SourceFormatInfo)) /
+ SourceFrameSize) * SourceFrameSize;
+ SkipOutputCount := 0;
+ end;
+
+ // copy data to front of buffer
+ if ((SampleBufferCount > 0) and (SampleBufferPos > 0)) then
+ Move(SampleBuffer[SampleBufferPos], SampleBuffer[0], SampleBufferCount);
+ SampleBufferPos := 0;
+
+ // resize buffer to a reasonable size
+ if (BufferSize > SampleBufferCount) then
+ begin
+ // Note: use BufferSize instead of BytesNeeded to minimize the need for resizing
+ SampleBufferSize := BufferSize;
+ ReallocMem(SampleBuffer, SampleBufferSize);
+ if (not assigned(SampleBuffer)) then
+ Exit;
+ end;
+
+ // fill sample-buffer (fetch and convert one block of source data per loop)
+ while (SampleBufferCount < BytesNeeded) do
+ begin
+ // move remaining source data from the previous pass to front of buffer
+ if (SourceBufferCount > 0) then
+ begin
+ Move(SourceBuffer[SourceBufferSize-SourceBufferCount],
+ SourceBuffer[0],
+ SourceBufferCount);
+ end;
+
+ SourceSize := SourceStream.ReadData(
+ @SourceBuffer[SourceBufferCount], SourceBufferSize-SourceBufferCount);
+ // break on error (-1) or if no data is available (0), e.g. while seeking
+ if (SourceSize <= 0) then
+ begin
+ // if we do not have data -> exit
+ if (SourceBufferCount = 0) then
+ begin
+ FlushBuffers();
+ Exit;
+ end;
+ // if we have some data, stop retrieving data from the source stream
+ // and use the data we have so far
+ Break;
+ end;
+
+ SourceBufferCount := SourceBufferCount + SourceSize;
+
+ // end-of-file reached -> stop playback
+ if (SourceStream.EOF) then
+ begin
+ if (Loop) then
+ SourceStream.Position := 0
+ else
+ Stop();
+ end;
+
+ if (SkipSourceCount > 0) then
+ begin
+ // skip data and update source buffer count
+ SourceBufferCount := SourceBufferCount - SkipSourceCount;
+ SkipSourceCount := -SourceBufferCount;
+ // continue with next pass if we skipped all data
+ if (SourceBufferCount <= 0) then
+ begin
+ SourceBufferCount := 0;
+ Continue;
+ end;
+ end;
+
+ // calc buffer size (might be bigger than actual resampled byte count)
+ ConversionOutputSize := Converter.GetOutputBufferSize(SourceBufferCount);
+ NeededSampleBufferSize := SampleBufferCount + ConversionOutputSize;
+
+ // resize buffer if necessary
+ if (SampleBufferSize < NeededSampleBufferSize) then
+ begin
+ SampleBufferSize := NeededSampleBufferSize;
+ ReallocMem(SampleBuffer, SampleBufferSize);
+ if (not assigned(SampleBuffer)) then
+ begin
+ FlushBuffers();
+ Exit;
+ end;
+ end;
+
+ // resample source data (Note: ConversionInputCount might be adjusted by Convert())
+ ConversionInputCount := SourceBufferCount;
+ ConversionOutputCount := Converter.Convert(
+ SourceBuffer, @SampleBuffer[SampleBufferCount], ConversionInputCount);
+ if (ConversionOutputCount = -1) then
+ begin
+ FlushBuffers();
+ Exit;
+ end;
+
+ // adjust sample- and source-buffer count by the number of converted bytes
+ SampleBufferCount := SampleBufferCount + ConversionOutputCount;
+ SourceBufferCount := SourceBufferCount - ConversionInputCount;
+ end;
+
+ // apply effects
+ ApplySoundEffects(SampleBuffer, SampleBufferCount);
+
+ // copy data to result buffer
+ CopyCount := Min(BytesNeeded, SampleBufferCount);
+ Move(SampleBuffer[0], Buffer[BufferSize - BytesNeeded], CopyCount);
+ Dec(BytesNeeded, CopyCount);
+ SampleBufferPos := CopyCount;
+
+ // release buffer lock
+ finally
+ UnlockSampleBuffer();
+ end;
+
+ // pad the buffer with the last frame if we are to fast
+ if (FillCount > 0) then
+ begin
+ if (CopyCount >= OutputFrameSize) then
+ PadFrame := @Buffer[CopyCount-OutputFrameSize]
+ else
+ PadFrame := nil;
+ FillBufferWithFrame(@Buffer[CopyCount], FillCount,
+ PadFrame, OutputFrameSize);
+ end;
+
+ // BytesNeeded now contains the number of remaining bytes we were not able to fetch
+ Result := BufferSize - BytesNeeded;
+end;
+
+function TGenericPlaybackStream.GetPCMData(var Data: TPCMData): Cardinal;
+var
+ ByteCount: integer;
+begin
+ Result := 0;
+
+ // just SInt16 stereo support for now
+ if ((Engine.GetAudioFormatInfo().Format <> asfS16) or
+ (Engine.GetAudioFormatInfo().Channels <> 2)) then
+ begin
+ Exit;
+ end;
+
+ // zero memory
+ FillChar(Data, SizeOf(Data), 0);
+
+ // TODO: At the moment just the first samples of the SampleBuffer
+ // are returned, even if there is newer data in the upper samples.
+
+ LockSampleBuffer();
+ ByteCount := Min(SizeOf(Data), SampleBufferCount);
+ if (ByteCount > 0) then
+ begin
+ Move(SampleBuffer[0], Data, ByteCount);
+ end;
+ UnlockSampleBuffer();
+
+ Result := ByteCount div SizeOf(TPCMStereoSample);
+end;
+
+procedure TGenericPlaybackStream.GetFFTData(var Data: TFFTData);
+var
+ i: integer;
+ Frames: integer;
+ DataIn: PSingleArray;
+ AudioFormat: TAudioFormatInfo;
+begin
+ // only works with SInt16 and Float values at the moment
+ AudioFormat := GetAudioFormatInfo();
+
+ DataIn := AllocMem(FFTSize * SizeOf(Single));
+ if (DataIn = nil) then
+ Exit;
+
+ LockSampleBuffer();
+ // TODO: We just use the first Frames frames, the others are ignored.
+ Frames := Min(FFTSize, SampleBufferCount div AudioFormat.FrameSize);
+ // use only first channel and convert data to float-values
+ case AudioFormat.Format of
+ asfS16:
+ begin
+ for i := 0 to Frames-1 do
+ DataIn[i] := PSmallInt(@SampleBuffer[i*AudioFormat.FrameSize])^ / -Low(SmallInt);
+ end;
+ asfFloat:
+ begin
+ for i := 0 to Frames-1 do
+ DataIn[i] := PSingle(@SampleBuffer[i*AudioFormat.FrameSize])^;
+ end;
+ end;
+ UnlockSampleBuffer();
+
+ WindowFunc(fwfHanning, FFTSize, DataIn);
+ PowerSpectrum(FFTSize, DataIn, @Data);
+ FreeMem(DataIn);
+
+ // resize data to a 0..1 range
+ for i := 0 to High(TFFTData) do
+ begin
+ Data[i] := Sqrt(Data[i]) / 100;
+ end;
+end;
+
+procedure TGenericPlaybackStream.AddSoundEffect(Effect: TSoundEffect);
+begin
+ if (not assigned(Effect)) then
+ Exit;
+
+ LockSampleBuffer();
+ // check if effect is already in list to avoid duplicates
+ if (SoundEffects.IndexOf(Pointer(Effect)) = -1) then
+ SoundEffects.Add(Pointer(Effect));
+ UnlockSampleBuffer();
+end;
+
+procedure TGenericPlaybackStream.RemoveSoundEffect(Effect: TSoundEffect);
+begin
+ LockSampleBuffer();
+ SoundEffects.Remove(Effect);
+ UnlockSampleBuffer();
+end;
+
+function TGenericPlaybackStream.GetPosition: real;
+var
+ BufferedTime: double;
+begin
+ if assigned(SourceStream) then
+ begin
+ LockSampleBuffer();
+
+ // calc the time of source data that is buffered (in the SampleBuffer and SourceBuffer)
+ // but not yet outputed
+ BufferedTime := (SampleBufferCount - SampleBufferPos) / Engine.FormatInfo.BytesPerSec +
+ SourceBufferCount / SourceStream.GetAudioFormatInfo().BytesPerSec;
+ // and subtract it from the source position
+ Result := SourceStream.Position - BufferedTime;
+
+ UnlockSampleBuffer();
+ end
+ else
+ begin
+ Result := -1;
+ end;
+end;
+
+procedure TGenericPlaybackStream.SetPosition(Time: real);
+begin
+ if assigned(SourceStream) then
+ begin
+ LockSampleBuffer();
+
+ SourceStream.Position := Time;
+ if (Status = ssStopped) then
+ NeedsRewind := false;
+ // do not use outdated data
+ FlushBuffers();
+
+ AvgSyncDiff := -1;
+
+ UnlockSampleBuffer();
+ end;
+end;
+
+function TGenericPlaybackStream.GetVolume(): single;
+var
+ FadeAmount: Single;
+begin
+ LockSampleBuffer();
+ // adjust volume if fading is enabled
+ if (FadeInTime > 0) then
+ begin
+ FadeAmount := (SDL_GetTicks() - FadeInStartTime) / FadeInTime;
+ // check if fade-target is reached
+ if (FadeAmount >= 1) then
+ begin
+ // target reached -> stop fading
+ FadeInTime := 0;
+ fVolume := FadeInTargetVolume;
+ end
+ else
+ begin
+ // fading in progress
+ fVolume := FadeAmount*FadeInTargetVolume + (1-FadeAmount)*FadeInStartVolume;
+ end;
+ end;
+ // return current volume
+ Result := fVolume;
+ UnlockSampleBuffer();
+end;
+
+procedure TGenericPlaybackStream.SetVolume(Volume: single);
+begin
+ LockSampleBuffer();
+ // stop fading
+ FadeInTime := 0;
+ // clamp volume
+ if (Volume > 1.0) then
+ fVolume := 1.0
+ else if (Volume < 0) then
+ fVolume := 0
+ else
+ fVolume := Volume;
+ UnlockSampleBuffer();
+end;
+
+
+{ TGenericVoiceStream }
+
+constructor TGenericVoiceStream.Create(Engine: TAudioPlayback_SoftMixer);
+begin
+ inherited Create();
+ Self.Engine := Engine;
+end;
+
+function TGenericVoiceStream.Open(ChannelMap: integer; FormatInfo: TAudioFormatInfo): boolean;
+var
+ BufferSize: integer;
+begin
+ Result := false;
+
+ Close();
+
+ if (not inherited Open(ChannelMap, FormatInfo)) then
+ Exit;
+
+ // Note:
+ // - use Self.FormatInfo instead of FormatInfo as the latter one might have a
+ // channel size of 2.
+ // - the buffer-size must be a multiple of the FrameSize
+ BufferSize := (Ceil(MAX_VOICE_DELAY * Self.FormatInfo.BytesPerSec) div Self.FormatInfo.FrameSize) *
+ Self.FormatInfo.FrameSize;
+ VoiceBuffer := TRingBuffer.Create(BufferSize);
+
+ BufferLock := SDL_CreateMutex();
+
+
+ // create a matching playback stream for the voice-stream
+ PlaybackStream := TGenericPlaybackStream.Create(Engine);
+ // link voice- and playback-stream
+ if (not PlaybackStream.Open(Self)) then
+ begin
+ PlaybackStream.Free;
+ Exit;
+ end;
+
+ // start voice passthrough
+ PlaybackStream.Play();
+
+ Result := true;
+end;
+
+procedure TGenericVoiceStream.Close();
+begin
+ // stop and free the playback stream
+ FreeAndNil(PlaybackStream);
+
+ // free data
+ FreeAndNil(VoiceBuffer);
+ if (BufferLock <> nil) then
+ SDL_DestroyMutex(BufferLock);
+
+ inherited Close();
+end;
+
+procedure TGenericVoiceStream.WriteData(Buffer: PChar; BufferSize: integer);
+begin
+ // lock access to buffer
+ SDL_mutexP(BufferLock);
+ try
+ if (VoiceBuffer = nil) then
+ Exit;
+ VoiceBuffer.Write(Buffer, BufferSize);
+ finally
+ SDL_mutexV(BufferLock);
+ end;
+end;
+
+function TGenericVoiceStream.ReadData(Buffer: PChar; BufferSize: integer): integer;
+begin
+ Result := -1;
+
+ // lock access to buffer
+ SDL_mutexP(BufferLock);
+ try
+ if (VoiceBuffer = nil) then
+ Exit;
+ Result := VoiceBuffer.Read(Buffer, BufferSize);
+ finally
+ SDL_mutexV(BufferLock);
+ end;
+end;
+
+function TGenericVoiceStream.IsEOF(): boolean;
+begin
+ SDL_mutexP(BufferLock);
+ Result := (VoiceBuffer = nil);
+ SDL_mutexV(BufferLock);
+end;
+
+function TGenericVoiceStream.IsError(): boolean;
+begin
+ Result := false;
+end;
+
+
+{ TAudioPlayback_SoftMixer }
+
+function TAudioPlayback_SoftMixer.InitializePlayback: boolean;
+begin
+ Result := false;
+
+ //Log.LogStatus('InitializePlayback', 'UAudioPlayback_SoftMixer');
+
+ if(not InitializeAudioPlaybackEngine()) then
+ Exit;
+
+ MixerStream := TAudioMixerStream.Create(Self);
+
+ if(not StartAudioPlaybackEngine()) then
+ Exit;
+
+ Result := true;
+end;
+
+function TAudioPlayback_SoftMixer.FinalizePlayback: boolean;
+begin
+ Close;
+ StopAudioPlaybackEngine();
+
+ FreeAndNil(MixerStream);
+ FreeAndNil(FormatInfo);
+
+ FinalizeAudioPlaybackEngine();
+ inherited FinalizePlayback;
+ Result := true;
+end;
+
+procedure TAudioPlayback_SoftMixer.AudioCallback(Buffer: PChar; Size: integer);
+begin
+ MixerStream.ReadData(Buffer, Size);
+end;
+
+function TAudioPlayback_SoftMixer.GetMixer(): TAudioMixerStream;
+begin
+ Result := MixerStream;
+end;
+
+function TAudioPlayback_SoftMixer.GetAudioFormatInfo(): TAudioFormatInfo;
+begin
+ Result := FormatInfo;
+end;
+
+function TAudioPlayback_SoftMixer.CreatePlaybackStream(): TAudioPlaybackStream;
+begin
+ Result := TGenericPlaybackStream.Create(Self);
+end;
+
+function TAudioPlayback_SoftMixer.CreateVoiceStream(ChannelMap: integer; FormatInfo: TAudioFormatInfo): TAudioVoiceStream;
+var
+ VoiceStream: TGenericVoiceStream;
+begin
+ Result := nil;
+
+ // create a voice stream
+ VoiceStream := TGenericVoiceStream.Create(Self);
+ if (not VoiceStream.Open(ChannelMap, FormatInfo)) then
+ begin
+ VoiceStream.Free;
+ Exit;
+ end;
+
+ Result := VoiceStream;
+end;
+
+procedure TAudioPlayback_SoftMixer.SetAppVolume(Volume: single);
+begin
+ // sets volume only for this application
+ MixerStream.Volume := Volume;
+end;
+
+procedure TAudioPlayback_SoftMixer.MixBuffers(DstBuffer, SrcBuffer: PChar; Size: Cardinal; Volume: Single);
+var
+ SampleIndex: Cardinal;
+ SampleInt: Integer;
+ SampleFlt: Single;
+begin
+ SampleIndex := 0;
+ case FormatInfo.Format of
+ asfS16:
+ begin
+ while (SampleIndex < Size) do
+ begin
+ // apply volume and sum with previous mixer value
+ SampleInt := PSmallInt(@DstBuffer[SampleIndex])^ +
+ Round(PSmallInt(@SrcBuffer[SampleIndex])^ * Volume);
+ // clip result
+ if (SampleInt > High(SmallInt)) then
+ SampleInt := High(SmallInt)
+ else if (SampleInt < Low(SmallInt)) then
+ SampleInt := Low(SmallInt);
+ // assign result
+ PSmallInt(@DstBuffer[SampleIndex])^ := SampleInt;
+ // increase index by one sample
+ Inc(SampleIndex, SizeOf(SmallInt));
+ end;
+ end;
+ asfFloat:
+ begin
+ while (SampleIndex < Size) do
+ begin
+ // apply volume and sum with previous mixer value
+ SampleFlt := PSingle(@DstBuffer[SampleIndex])^ +
+ PSingle(@SrcBuffer[SampleIndex])^ * Volume;
+ // clip result
+ if (SampleFlt > 1.0) then
+ SampleFlt := 1.0
+ else if (SampleFlt < -1.0) then
+ SampleFlt := -1.0;
+ // assign result
+ PSingle(@DstBuffer[SampleIndex])^ := SampleFlt;
+ // increase index by one sample
+ Inc(SampleIndex, SizeOf(Single));
+ end;
+ end;
+ else
+ begin
+ Log.LogError('Incompatible format', 'TAudioMixerStream.MixAudio');
+ end;
+ end;
+end;
+
+end.