Files
Aerofoil/AerofoilSDL/GpAudioDriver_SDL2.cpp

739 lines
19 KiB
C++

#include "CoreDefs.h"
#include "IGpAudioBuffer.h"
#include "IGpAudioDriver.h"
#include "IGpAudioChannel.h"
#include "IGpAudioChannelCallbacks.h"
#include "IGpMutex.h"
#include "IGpPrefsHandler.h"
#include "IGpSystemServices.h"
#include "GpAudioDriverProperties.h"
#include "GpSDL.h"
#include "SDL_audio.h"
#include "GpRingBuffer.h"
#include "SDL_atomic.h"
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <new>
#include <stdio.h>
#include <chrono>
class GpAudioDriver_SDL2;
typedef std::chrono::high_resolution_clock::duration GpAudioDriver_SDL2_Duration_t;
typedef std::chrono::high_resolution_clock::time_point GpAudioDriver_SDL2_TimePoint_t;
typedef std::chrono::high_resolution_clock::period GpAudioDriver_SDL2_Period_t;
typedef std::chrono::high_resolution_clock::rep GpAudioDriver_SDL2_Rep_t;
static void *AlignedAlloc(size_t size, size_t alignment)
{
void *storage = malloc(size + alignment);
if (!storage)
return nullptr;
uintptr_t alignedPtr = reinterpret_cast<uintptr_t>(storage);
size_t padding = alignment - static_cast<size_t>(alignedPtr % alignment);
uint8_t *storageLoc = static_cast<uint8_t*>(storage);
uint8_t *objectLoc = storageLoc + padding;
uint8_t *paddingSizeLoc = storageLoc + padding - 1;
*reinterpret_cast<uint8_t*>(paddingSizeLoc) = static_cast<uint8_t>(padding);
return objectLoc;
}
static void AlignedFree(void *ptr)
{
size_t padding = static_cast<uint8_t*>(ptr)[-1];
void *storageLoc = static_cast<uint8_t*>(ptr) - padding;
free(storageLoc);
}
class GpAudioBuffer_SDL2 final : public IGpAudioBuffer
{
public:
static GpAudioBuffer_SDL2 *Create(const void *data, size_t size);
void AddRef() override;
void Release() override;
const void *GetData() const;
size_t GetSize() const;
private:
GpAudioBuffer_SDL2(const void *data, size_t size);
~GpAudioBuffer_SDL2();
void Destroy();
const void *m_data;
size_t m_size;
SDL_atomic_t m_count;
};
GpAudioBuffer_SDL2 *GpAudioBuffer_SDL2::Create(const void *data, size_t size)
{
void *storage = malloc(size + sizeof(GpAudioBuffer_SDL2));
if (!storage)
return nullptr;
void *dataPos = static_cast<uint8_t*>(storage) + sizeof(GpAudioBuffer_SDL2);
memcpy(dataPos, data, size);
return new (storage) GpAudioBuffer_SDL2(dataPos, size);
}
void GpAudioBuffer_SDL2::AddRef()
{
SDL_AtomicAdd(&m_count, 1);
}
void GpAudioBuffer_SDL2::Release()
{
int prevCount = SDL_AtomicAdd(&m_count, -1);
if (prevCount == 1)
this->Destroy();
}
const void *GpAudioBuffer_SDL2::GetData() const
{
return m_data;
}
size_t GpAudioBuffer_SDL2::GetSize() const
{
return m_size;
}
GpAudioBuffer_SDL2::GpAudioBuffer_SDL2(const void *data, size_t size)
: m_data(data)
, m_size(size)
{
SDL_AtomicSet(&m_count, 1);
}
GpAudioBuffer_SDL2::~GpAudioBuffer_SDL2()
{
}
void GpAudioBuffer_SDL2::Destroy()
{
this->~GpAudioBuffer_SDL2();
free(this);
}
class GpAudioChannel_SDL2 final : public IGpAudioChannel
{
public:
friend class GpAudioDriver_SDL2;
GpAudioChannel_SDL2(GpAudioDriver_SDL2_Duration_t latency, GpAudioDriver_SDL2_Duration_t bufferTime, size_t bufferSamplesMax, uint16_t sampleRate);
~GpAudioChannel_SDL2();
void AddRef();
void Release();
void SetAudioChannelContext(IGpAudioChannelCallbacks *callbacks) override;
bool PostBuffer(IGpAudioBuffer *buffer) override;
void Stop() override;
void Destroy() override;
void Consume(uint8_t *output, size_t sz, GpAudioDriver_SDL2_TimePoint_t mixStartTime, GpAudioDriver_SDL2_TimePoint_t mixEndTime);
static GpAudioChannel_SDL2 *Alloc(GpAudioDriver_SDL2 *driver, GpAudioDriver_SDL2_Duration_t latency, GpAudioDriver_SDL2_Duration_t bufferTime, size_t bufferSamplesMax, uint16_t sampleRate);
private:
bool Init(GpAudioDriver_SDL2 *driver);
static const size_t kMaxBuffers = 16;
IGpAudioChannelCallbacks *m_callbacks;
IGpMutex *m_mutex;
GpAudioDriver_SDL2 *m_owner;
SDL_atomic_t m_refCount;
GpAudioBuffer_SDL2 *m_pendingBuffers[kMaxBuffers];
size_t m_nextPendingBufferConsumePos;
size_t m_nextPendingBufferInsertionPos;
size_t m_numQueuedBuffers;
size_t m_firstBufferSamplesConsumed;
GpAudioDriver_SDL2_TimePoint_t m_timestamp; // Time that audio will be consumed if posted to the channel, if m_hasTimestamp is true.
GpAudioDriver_SDL2_Duration_t m_latency;
GpAudioDriver_SDL2_Duration_t m_bufferTime;
size_t m_bufferSamplesMax;
size_t m_leadingSilence;
uint16_t m_sampleRate;
bool m_isMixing;
bool m_hasTimestamp;
};
class GpAudioDriver_SDL2 final : public IGpAudioDriver, public IGpPrefsHandler
{
public:
friend class GpAudioChannel_SDL2;
explicit GpAudioDriver_SDL2(const GpAudioDriverProperties &properties);
~GpAudioDriver_SDL2();
IGpAudioBuffer *CreateBuffer(const void *data, size_t size) override;
IGpAudioChannel *CreateChannel() override;
void SetMasterVolume(uint32_t vol, uint32_t maxVolume) override;
void Shutdown() override;
IGpPrefsHandler *GetPrefsHandler() const override;
void ApplyPrefs(const void *identifier, size_t identifierSize, const void *contents, size_t contentsSize, uint32_t version) override;
bool SavePrefs(void *context, WritePrefsFunc_t writeFunc) override;
bool Init();
static GpAudioDriver_SDL2_TimePoint_t GetCurrentTime();
private:
void DetachAudioChannel(GpAudioChannel_SDL2 *channel);
static void SDLCALL StaticMixAudio(void *userdata, Uint8 *stream, int len);
void MixAudio(void *stream, size_t len);
void RefillMixChunk(GpAudioChannel_SDL2 *const*channels, size_t numChannels, size_t maxSamplesToFill, GpAudioDriver_SDL2_TimePoint_t mixStartTime, GpAudioDriver_SDL2_TimePoint_t mixEndTime);
GpAudioDriverProperties m_properties;
IGpMutex *m_mutex;
IGpMutex *m_mixState;
static const size_t kMaxChannels = 16;
static const size_t kMixChunkSize = 512;
static const int16_t kMaxAudioVolumeScale = 64;
GpAudioChannel_SDL2 *m_channels[kMaxChannels];
size_t m_numChannels;
unsigned int m_sampleRate;
GpAudioDriver_SDL2_Duration_t m_latency;
GpAudioDriver_SDL2_Duration_t m_bufferTime;
size_t m_bufferSamples;
bool m_sdlAudioRunning;
GP_ALIGNED(GP_SYSTEM_MEMORY_ALIGNMENT) int16_t m_mixChunk[kMixChunkSize];
size_t m_mixChunkReadOffset;
int16_t m_audioVolumeScale;
};
/////////////////////////////////////////////////////////////////////////////////////////
// GpAudioChannel
GpAudioChannel_SDL2::GpAudioChannel_SDL2(GpAudioDriver_SDL2_Duration_t latency, GpAudioDriver_SDL2_Duration_t bufferTime, size_t bufferSamplesMax, uint16_t sampleRate)
: m_callbacks(nullptr)
, m_mutex(nullptr)
, m_owner(nullptr)
, m_latency(latency)
, m_bufferTime(bufferTime)
, m_bufferSamplesMax(bufferSamplesMax)
, m_leadingSilence(0)
, m_sampleRate(sampleRate)
, m_isMixing(false)
, m_hasTimestamp(false)
, m_nextPendingBufferConsumePos(0)
, m_nextPendingBufferInsertionPos(0)
, m_numQueuedBuffers(0)
, m_firstBufferSamplesConsumed(0)
{
SDL_AtomicSet(&m_refCount, 1);
}
GpAudioChannel_SDL2::~GpAudioChannel_SDL2()
{
Stop();
if (m_mutex)
m_mutex->Destroy();
assert(m_numQueuedBuffers == 0);
}
void GpAudioChannel_SDL2::AddRef()
{
SDL_AtomicIncRef(&m_refCount);
}
void GpAudioChannel_SDL2::Release()
{
if (SDL_AtomicDecRef(&m_refCount))
{
this->~GpAudioChannel_SDL2();
AlignedFree(this);
}
}
void GpAudioChannel_SDL2::SetAudioChannelContext(IGpAudioChannelCallbacks *callbacks)
{
m_callbacks = callbacks;
}
bool GpAudioChannel_SDL2::PostBuffer(IGpAudioBuffer *buffer)
{
buffer->AddRef();
m_mutex->Lock();
if (m_numQueuedBuffers == kMaxBuffers)
{
m_mutex->Unlock();
buffer->Release();
return false;
}
size_t leadingSilence = 0;
if (m_numQueuedBuffers == 0 && m_hasTimestamp && !m_isMixing)
{
GpAudioDriver_SDL2_TimePoint_t queueTime = GpAudioDriver_SDL2::GetCurrentTime() + m_latency;
if (queueTime > m_timestamp)
{
const GpAudioDriver_SDL2_Duration_t leadTime = queueTime - m_timestamp;
if (leadTime > m_bufferTime)
leadingSilence = m_bufferSamplesMax;
else
{
const GpAudioDriver_SDL2_Rep_t leadTimeRep = leadTime.count();
leadingSilence = leadTimeRep * static_cast<GpAudioDriver_SDL2_Rep_t>(m_sampleRate) * GpAudioDriver_SDL2_Period_t::num / GpAudioDriver_SDL2_Period_t::den;
}
}
}
m_leadingSilence = leadingSilence;
m_pendingBuffers[m_nextPendingBufferInsertionPos++] = static_cast<GpAudioBuffer_SDL2*>(buffer);
m_numQueuedBuffers++;
m_nextPendingBufferInsertionPos = m_nextPendingBufferInsertionPos % kMaxBuffers;
m_mutex->Unlock();
return true;
}
void GpAudioChannel_SDL2::Stop()
{
m_mutex->Lock();
m_leadingSilence = 0;
size_t numBuffersToDischarge = m_numQueuedBuffers;
for (size_t i = 0; i < numBuffersToDischarge; i++)
{
GpAudioBuffer_SDL2 *buffer = m_pendingBuffers[m_nextPendingBufferConsumePos];
m_nextPendingBufferConsumePos = (m_nextPendingBufferConsumePos + 1) % kMaxBuffers;
m_numQueuedBuffers--;
m_firstBufferSamplesConsumed = 0;
if (m_callbacks)
m_callbacks->NotifyBufferFinished();
buffer->Release();
}
m_mutex->Unlock();
}
void GpAudioChannel_SDL2::Destroy()
{
if (m_owner)
m_owner->DetachAudioChannel(this);
this->Release();
}
bool GpAudioChannel_SDL2::Init(GpAudioDriver_SDL2 *driver)
{
m_owner = driver;
m_mutex = driver->m_properties.m_systemServices->CreateRecursiveMutex();
if (!m_mutex)
return false;
return true;
}
void GpAudioChannel_SDL2::Consume(uint8_t *output, size_t sz, GpAudioDriver_SDL2_TimePoint_t mixStartTime, GpAudioDriver_SDL2_TimePoint_t mixEndTime)
{
m_mutex->Lock();
m_isMixing = true;
m_hasTimestamp = true;
m_timestamp = mixEndTime;
if (sz <= m_leadingSilence)
{
memset(output, 0x80, sz);
m_leadingSilence -= sz;
m_isMixing = false;
m_mutex->Unlock();
return;
}
else
{
size_t leadingSilence = m_leadingSilence;
if (leadingSilence > 0)
{
memset(output, 0x80, leadingSilence);
output += leadingSilence;
sz -= leadingSilence;
m_leadingSilence = 0;
}
}
while (m_numQueuedBuffers > 0)
{
GpAudioBuffer_SDL2 *buffer = m_pendingBuffers[m_nextPendingBufferConsumePos];
const void *bufferData = buffer->GetData();
const size_t bufferSize = buffer->GetSize();
assert(m_firstBufferSamplesConsumed < bufferSize);
const size_t available = (bufferSize - m_firstBufferSamplesConsumed);
if (available <= sz)
{
memcpy(output, static_cast<const uint8_t*>(bufferData) + m_firstBufferSamplesConsumed, available);
sz -= available;
output += available;
m_nextPendingBufferConsumePos = (m_nextPendingBufferConsumePos + 1) % kMaxBuffers;
m_numQueuedBuffers--;
m_firstBufferSamplesConsumed = 0;
if (m_callbacks)
m_callbacks->NotifyBufferFinished();
buffer->Release();
if (sz == 0)
break;
}
else
{
memcpy(output, static_cast<const uint8_t*>(bufferData) + m_firstBufferSamplesConsumed, sz);
m_firstBufferSamplesConsumed += sz;
output += sz;
sz = 0;
break;
}
}
m_isMixing = false;
m_mutex->Unlock();
memset(output, 0x80, sz);
}
GpAudioChannel_SDL2 *GpAudioChannel_SDL2::Alloc(GpAudioDriver_SDL2 *driver, GpAudioDriver_SDL2_Duration_t latency, GpAudioDriver_SDL2_Duration_t bufferTime, size_t bufferSamplesMax, uint16_t sampleRate)
{
void *storage = AlignedAlloc(sizeof(GpAudioChannel_SDL2), GP_SYSTEM_MEMORY_ALIGNMENT);
if (!storage)
return nullptr;
GpAudioChannel_SDL2 *channel = new (storage) GpAudioChannel_SDL2(latency, bufferTime, bufferSamplesMax, sampleRate);
if (!channel->Init(driver))
{
channel->Destroy();
return nullptr;
}
return channel;
}
/////////////////////////////////////////////////////////////////////////////////////////
// GpAudioDriver_SDL2
GpAudioDriver_SDL2::GpAudioDriver_SDL2(const GpAudioDriverProperties &properties)
: m_properties(properties)
, m_mutex(nullptr)
, m_numChannels(0)
, m_sampleRate(0)
, m_latency(GpAudioDriver_SDL2_Duration_t::zero())
, m_bufferTime(GpAudioDriver_SDL2_Duration_t::zero())
, m_sdlAudioRunning(false)
, m_mixChunkReadOffset(kMixChunkSize)
, m_audioVolumeScale(kMaxAudioVolumeScale)
{
for (size_t i = 0; i < kMaxChannels; i++)
m_channels[i] = nullptr;
for (size_t i = 0; i < kMixChunkSize; i++)
m_mixChunk[i] = 0;
}
GpAudioDriver_SDL2::~GpAudioDriver_SDL2()
{
if (m_sdlAudioRunning)
SDL_CloseAudio();
if (m_mutex)
m_mutex->Destroy();
}
IGpAudioBuffer *GpAudioDriver_SDL2::CreateBuffer(const void *data, size_t size)
{
return GpAudioBuffer_SDL2::Create(data, size);
}
IGpAudioChannel *GpAudioDriver_SDL2::CreateChannel()
{
GpAudioChannel_SDL2 *newChannel = GpAudioChannel_SDL2::Alloc(this, m_latency, m_bufferTime, m_bufferSamples, m_sampleRate);
if (!newChannel)
return nullptr;
m_mutex->Lock();
if (m_numChannels == kMaxChannels)
{
newChannel->Destroy();
m_mutex->Unlock();
return nullptr;
}
m_channels[m_numChannels] = newChannel;
m_numChannels++;
m_mutex->Unlock();
return newChannel;
}
void GpAudioDriver_SDL2::SetMasterVolume(uint32_t vol, uint32_t maxVolume)
{
double scale = vol * static_cast<uint64_t>(kMaxAudioVolumeScale) / maxVolume;
m_audioVolumeScale = static_cast<int16_t>(scale);
}
void GpAudioDriver_SDL2::Shutdown()
{
this->~GpAudioDriver_SDL2();
AlignedFree(this);
}
IGpPrefsHandler *GpAudioDriver_SDL2::GetPrefsHandler() const
{
return const_cast<GpAudioDriver_SDL2*>(this);
}
void GpAudioDriver_SDL2::ApplyPrefs(const void *identifier, size_t identifierSize, const void *contents, size_t contentsSize, uint32_t version)
{
}
bool GpAudioDriver_SDL2::SavePrefs(void *context, WritePrefsFunc_t writeFunc)
{
return true;
}
bool GpAudioDriver_SDL2::Init()
{
m_mutex = m_properties.m_systemServices->CreateMutex();
if (!m_mutex)
return false;
SDL_AudioSpec requestedSpec;
memset(&requestedSpec, 0, sizeof(requestedSpec));
requestedSpec.callback = GpAudioDriver_SDL2::StaticMixAudio;
requestedSpec.channels = 1;
requestedSpec.format = AUDIO_S16;
requestedSpec.freq = m_properties.m_sampleRate;
requestedSpec.samples = kMixChunkSize;
requestedSpec.userdata = this;
if (SDL_OpenAudio(&requestedSpec, nullptr))
{
requestedSpec.freq = 22050;
if (SDL_OpenAudio(&requestedSpec, nullptr))
return false;
}
SDL_PauseAudio(0);
m_sdlAudioRunning = true;
m_sampleRate = requestedSpec.freq;
m_latency = GpAudioDriver_SDL2_Duration_t(static_cast<GpAudioDriver_SDL2_Rep_t>(GpAudioDriver_SDL2_Period_t::den * requestedSpec.samples / GpAudioDriver_SDL2_Period_t::num / m_sampleRate));
m_bufferTime = GpAudioDriver_SDL2_Duration_t(static_cast<GpAudioDriver_SDL2_Rep_t>(GpAudioDriver_SDL2_Period_t::den * requestedSpec.samples / GpAudioDriver_SDL2_Period_t::num / m_sampleRate));
m_bufferSamples = requestedSpec.samples;
return true;
}
void GpAudioDriver_SDL2::DetachAudioChannel(GpAudioChannel_SDL2 *channel)
{
m_mutex->Lock();
const size_t numChannels = m_numChannels;
for (size_t i = 0; i < numChannels; i++)
{
if (m_channels[i] == channel)
{
m_numChannels = numChannels - 1;
m_channels[i] = m_channels[numChannels - 1];
m_channels[numChannels - 1] = nullptr;
break;
}
}
m_mutex->Unlock();
}
void GpAudioDriver_SDL2::StaticMixAudio(void *userdata, Uint8 *stream, int len)
{
static_cast<GpAudioDriver_SDL2*>(userdata)->MixAudio(stream, static_cast<size_t>(len));
}
void GpAudioDriver_SDL2::MixAudio(void *stream, size_t len)
{
GpAudioChannel_SDL2 *mixingChannels[kMaxChannels];
size_t numChannels = 0;
m_mutex->Lock();
numChannels = m_numChannels;
for (size_t i = 0; i < numChannels; i++)
{
GpAudioChannel_SDL2 *channel = m_channels[i];
channel->AddRef();
mixingChannels[i] = channel;
}
m_mutex->Unlock();
const size_t totalSamples = len / sizeof(int16_t);
size_t samplesRemaining = totalSamples;
GpAudioDriver_SDL2_TimePoint_t audioMixStartTime = GpAudioDriver_SDL2::GetCurrentTime();
GpAudioDriver_SDL2_TimePoint_t audioMixBlockStartTime = audioMixStartTime;
size_t samplesSinceStart = 0;
for (;;)
{
size_t availableInMixChunk = kMixChunkSize - m_mixChunkReadOffset;
if (availableInMixChunk > samplesRemaining)
{
m_mixChunkReadOffset += samplesRemaining;
memcpy(stream, m_mixChunk + m_mixChunkReadOffset, samplesRemaining * sizeof(int16_t));
break;
}
else
{
memcpy(stream, m_mixChunk + m_mixChunkReadOffset, availableInMixChunk * sizeof(int16_t));
stream = static_cast<int16_t*>(stream) + availableInMixChunk;
samplesSinceStart += availableInMixChunk;
GpAudioDriver_SDL2_Duration_t audioMixDurationSinceStart = GpAudioDriver_SDL2_Duration_t(static_cast<GpAudioDriver_SDL2_Rep_t>(GpAudioDriver_SDL2_Period_t::den * samplesSinceStart / GpAudioDriver_SDL2_Period_t::num / m_sampleRate));
GpAudioDriver_SDL2_TimePoint_t audioMixBlockEndTime = audioMixStartTime + audioMixDurationSinceStart;
m_mixChunkReadOffset = 0;
RefillMixChunk(mixingChannels, numChannels, samplesRemaining, audioMixBlockStartTime, audioMixBlockEndTime);
audioMixBlockStartTime = audioMixBlockEndTime;
samplesRemaining -= availableInMixChunk;
}
}
for (size_t i = 0; i < numChannels; i++)
mixingChannels[i]->Release();
}
void GpAudioDriver_SDL2::RefillMixChunk(GpAudioChannel_SDL2 *const*channels, size_t numChannels, size_t maxSamplesToFill, GpAudioDriver_SDL2_TimePoint_t mixStartTime, GpAudioDriver_SDL2_TimePoint_t mixEndTime)
{
uint8_t audioMixBufferUnaligned[kMixChunkSize + GP_SYSTEM_MEMORY_ALIGNMENT];
uint8_t *audioMixBuffer = audioMixBufferUnaligned;
{
uintptr_t bufferPtr = reinterpret_cast<uintptr_t>(audioMixBuffer);
size_t alignPadding = GP_SYSTEM_MEMORY_ALIGNMENT - (bufferPtr % GP_SYSTEM_MEMORY_ALIGNMENT);
audioMixBuffer += alignPadding;
}
bool noAudio = true;
const int16_t audioVolumeScale = m_audioVolumeScale;
size_t samplesToFill = kMixChunkSize;
if (samplesToFill > maxSamplesToFill)
{
m_mixChunkReadOffset += samplesToFill - maxSamplesToFill;
samplesToFill = maxSamplesToFill;
}
else
m_mixChunkReadOffset = 0;
int16_t *mixChunkStart = m_mixChunk + m_mixChunkReadOffset;
int16_t audioNormalizeShift = 0;
for (size_t i = 0; i < numChannels; i++)
{
channels[i]->Consume(audioMixBuffer, samplesToFill, mixStartTime, mixEndTime);
if (i == 0)
{
noAudio = false;
audioNormalizeShift = 0x80;
for (size_t j = 0; j < samplesToFill; j++)
mixChunkStart[j] = static_cast<int16_t>(audioMixBuffer[j]);
}
else
{
audioNormalizeShift += 0x80;
for (size_t j = 0; j < samplesToFill; j++)
mixChunkStart[j] += static_cast<int16_t>(audioMixBuffer[j]);
}
}
if (noAudio)
memset(mixChunkStart, 0, samplesToFill * sizeof(mixChunkStart[0]));
else
{
for (size_t i = 0; i < samplesToFill; i++)
mixChunkStart[i] = (mixChunkStart[i] - audioNormalizeShift) * audioVolumeScale;
}
}
GpAudioDriver_SDL2_TimePoint_t GpAudioDriver_SDL2::GetCurrentTime()
{
return std::chrono::high_resolution_clock::now();
}
IGpAudioDriver *GpDriver_CreateAudioDriver_SDL(const GpAudioDriverProperties &properties)
{
void *storage = AlignedAlloc(sizeof(GpAudioDriver_SDL2), GP_SYSTEM_MEMORY_ALIGNMENT);
if (!storage)
return nullptr;
GpAudioDriver_SDL2 *driver = new (storage) GpAudioDriver_SDL2(properties);
if (!driver->Init())
{
driver->Shutdown();
return nullptr;
}
return driver;
}