7 files changed, 351 insertions, 19 deletions

diff --git a/src/audio_core/sink/cubeb_sink.cpp b/src/audio_core/sink/cubeb_sink.cpp
index 51a23fe15..d97ca2a40 100644
--- a/src/audio_core/sink/cubeb_sink.cpp
+++ b/src/audio_core/sink/cubeb_sink.cpp
@@ -253,8 +253,9 @@ CubebSink::~CubebSink() {
 #endif
 }
 
-SinkStream* CubebSink::AcquireSinkStream(Core::System& system, u32 system_channels,
+SinkStream* CubebSink::AcquireSinkStream(Core::System& system, u32 system_channels_,
                                          const std::string& name, StreamType type) {
+    system_channels = system_channels_;
     SinkStreamPtr& stream = sink_streams.emplace_back(std::make_unique<CubebSinkStream>(
         ctx, device_channels, system_channels, output_device, input_device, name, type, system));
 
diff --git a/src/audio_core/sink/oboe_sink.cpp b/src/audio_core/sink/oboe_sink.cpp
new file mode 100644
index 000000000..e61841172
--- /dev/null
+++ b/src/audio_core/sink/oboe_sink.cpp
@@ -0,0 +1,223 @@
+// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <span>
+#include <vector>
+
+#include <oboe/Oboe.h>
+
+#include "audio_core/common/common.h"
+#include "audio_core/sink/oboe_sink.h"
+#include "audio_core/sink/sink_stream.h"
+#include "common/logging/log.h"
+#include "common/scope_exit.h"
+#include "core/core.h"
+
+namespace AudioCore::Sink {
+
+class OboeSinkStream final : public SinkStream,
+                             public oboe::AudioStreamDataCallback,
+                             public oboe::AudioStreamErrorCallback {
+public:
+    explicit OboeSinkStream(Core::System& system_, StreamType type_, const std::string& name_,
+                            u32 system_channels_)
+        : SinkStream(system_, type_) {
+        name = name_;
+        system_channels = system_channels_;
+
+        this->OpenStream();
+    }
+
+    ~OboeSinkStream() override {
+        LOG_INFO(Audio_Sink, "Destroyed Oboe stream");
+    }
+
+    void Finalize() override {
+        this->Stop();
+        m_stream.reset();
+    }
+
+    void Start(bool resume = false) override {
+        if (!m_stream || !paused) {
+            return;
+        }
+
+        paused = false;
+
+        if (m_stream->start() != oboe::Result::OK) {
+            LOG_CRITICAL(Audio_Sink, "Error starting Oboe stream");
+        }
+    }
+
+    void Stop() override {
+        if (!m_stream || paused) {
+            return;
+        }
+
+        this->SignalPause();
+
+        if (m_stream->stop() != oboe::Result::OK) {
+            LOG_CRITICAL(Audio_Sink, "Error stopping Oboe stream");
+        }
+    }
+
+public:
+    static s32 QueryChannelCount(oboe::Direction direction) {
+        std::shared_ptr<oboe::AudioStream> temp_stream;
+        oboe::AudioStreamBuilder builder;
+
+        const auto result = ConfigureBuilder(builder, direction)->openStream(temp_stream);
+        ASSERT(result == oboe::Result::OK);
+
+        return temp_stream->getChannelCount() >= 6 ? 6 : 2;
+    }
+
+protected:
+    oboe::DataCallbackResult onAudioReady(oboe::AudioStream*, void* audio_data,
+                                          s32 num_buffer_frames) override {
+        const size_t num_channels = this->GetDeviceChannels();
+        const size_t frame_size = num_channels;
+        const size_t num_frames = static_cast<size_t>(num_buffer_frames);
+
+        if (type == StreamType::In) {
+            std::span<const s16> input_buffer{reinterpret_cast<const s16*>(audio_data),
+                                              num_frames * frame_size};
+            this->ProcessAudioIn(input_buffer, num_frames);
+        } else {
+            std::span<s16> output_buffer{reinterpret_cast<s16*>(audio_data),
+                                         num_frames * frame_size};
+            this->ProcessAudioOutAndRender(output_buffer, num_frames);
+        }
+
+        return oboe::DataCallbackResult::Continue;
+    }
+
+    void onErrorAfterClose(oboe::AudioStream*, oboe::Result) override {
+        LOG_INFO(Audio_Sink, "Audio stream closed, reinitializing");
+
+        if (this->OpenStream()) {
+            m_stream->start();
+        }
+    }
+
+private:
+    static oboe::AudioStreamBuilder* ConfigureBuilder(oboe::AudioStreamBuilder& builder,
+                                                      oboe::Direction direction) {
+        // TODO: investigate callback delay issues when using AAudio
+        return builder.setPerformanceMode(oboe::PerformanceMode::LowLatency)
+            ->setAudioApi(oboe::AudioApi::OpenSLES)
+            ->setDirection(direction)
+            ->setSampleRate(TargetSampleRate)
+            ->setSampleRateConversionQuality(oboe::SampleRateConversionQuality::High)
+            ->setFormat(oboe::AudioFormat::I16)
+            ->setFormatConversionAllowed(true)
+            ->setUsage(oboe::Usage::Game)
+            ->setBufferCapacityInFrames(TargetSampleCount * 2);
+    }
+
+    bool OpenStream() {
+        const auto direction = [&]() {
+            switch (type) {
+            case StreamType::In:
+                return oboe::Direction::Input;
+            case StreamType::Out:
+            case StreamType::Render:
+                return oboe::Direction::Output;
+            default:
+                ASSERT(false);
+                return oboe::Direction::Output;
+            }
+        }();
+
+        const auto expected_channels = QueryChannelCount(direction);
+        const auto expected_mask = [&]() {
+            switch (expected_channels) {
+            case 1:
+                return oboe::ChannelMask::Mono;
+            case 2:
+                return oboe::ChannelMask::Stereo;
+            case 6:
+                return oboe::ChannelMask::CM5Point1;
+            default:
+                ASSERT(false);
+                return oboe::ChannelMask::Unspecified;
+            }
+        }();
+
+        oboe::AudioStreamBuilder builder;
+        const auto result = ConfigureBuilder(builder, direction)
+                                ->setChannelCount(expected_channels)
+                                ->setChannelMask(expected_mask)
+                                ->setChannelConversionAllowed(true)
+                                ->setDataCallback(this)
+                                ->setErrorCallback(this)
+                                ->openStream(m_stream);
+        ASSERT(result == oboe::Result::OK);
+        return result == oboe::Result::OK && this->SetStreamProperties();
+    }
+
+    bool SetStreamProperties() {
+        ASSERT(m_stream);
+
+        m_stream->setBufferSizeInFrames(TargetSampleCount * 2);
+        device_channels = m_stream->getChannelCount();
+
+        const auto sample_rate = m_stream->getSampleRate();
+        const auto buffer_capacity = m_stream->getBufferCapacityInFrames();
+        const auto stream_backend =
+            m_stream->getAudioApi() == oboe::AudioApi::AAudio ? "AAudio" : "OpenSLES";
+
+        LOG_INFO(Audio_Sink, "Opened Oboe {} stream with {} channels sample rate {} capacity {}",
+                 stream_backend, device_channels, sample_rate, buffer_capacity);
+
+        return true;
+    }
+
+    std::shared_ptr<oboe::AudioStream> m_stream{};
+};
+
+OboeSink::OboeSink() {
+    // TODO: This is not generally knowable
+    // The channel count is distinct based on direction and can change
+    device_channels = OboeSinkStream::QueryChannelCount(oboe::Direction::Output);
+}
+
+OboeSink::~OboeSink() = default;
+
+SinkStream* OboeSink::AcquireSinkStream(Core::System& system, u32 system_channels,
+                                        const std::string& name, StreamType type) {
+    SinkStreamPtr& stream = sink_streams.emplace_back(
+        std::make_unique<OboeSinkStream>(system, type, name, system_channels));
+
+    return stream.get();
+}
+
+void OboeSink::CloseStream(SinkStream* to_remove) {
+    sink_streams.remove_if([&](auto& stream) { return stream.get() == to_remove; });
+}
+
+void OboeSink::CloseStreams() {
+    sink_streams.clear();
+}
+
+f32 OboeSink::GetDeviceVolume() const {
+    if (sink_streams.empty()) {
+        return 1.0f;
+    }
+
+    return sink_streams.front()->GetDeviceVolume();
+}
+
+void OboeSink::SetDeviceVolume(f32 volume) {
+    for (auto& stream : sink_streams) {
+        stream->SetDeviceVolume(volume);
+    }
+}
+
+void OboeSink::SetSystemVolume(f32 volume) {
+    for (auto& stream : sink_streams) {
+        stream->SetSystemVolume(volume);
+    }
+}
+
+} // namespace AudioCore::Sink
diff --git a/src/audio_core/sink/oboe_sink.h b/src/audio_core/sink/oboe_sink.h
new file mode 100644
index 000000000..8f6f54ab5
--- /dev/null
+++ b/src/audio_core/sink/oboe_sink.h
@@ -0,0 +1,75 @@
+// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <list>
+#include <string>
+
+#include "audio_core/sink/sink.h"
+
+namespace Core {
+class System;
+}
+
+namespace AudioCore::Sink {
+class SinkStream;
+
+class OboeSink final : public Sink {
+public:
+    explicit OboeSink();
+    ~OboeSink() override;
+
+    /**
+     * Create a new sink stream.
+     *
+     * @param system          - Core system.
+     * @param system_channels - Number of channels the audio system expects.
+     *                          May differ from the device's channel count.
+     * @param name            - Name of this stream.
+     * @param type            - Type of this stream, render/in/out.
+     *
+     * @return A pointer to the created SinkStream
+     */
+    SinkStream* AcquireSinkStream(Core::System& system, u32 system_channels,
+                                  const std::string& name, StreamType type) override;
+
+    /**
+     * Close a given stream.
+     *
+     * @param stream - The stream to close.
+     */
+    void CloseStream(SinkStream* stream) override;
+
+    /**
+     * Close all streams.
+     */
+    void CloseStreams() override;
+
+    /**
+     * Get the device volume. Set from calls to the IAudioDevice service.
+     *
+     * @return Volume of the device.
+     */
+    f32 GetDeviceVolume() const override;
+
+    /**
+     * Set the device volume. Set from calls to the IAudioDevice service.
+     *
+     * @param volume - New volume of the device.
+     */
+    void SetDeviceVolume(f32 volume) override;
+
+    /**
+     * Set the system volume. Comes from the audio system using this stream.
+     *
+     * @param volume - New volume of the system.
+     */
+    void SetSystemVolume(f32 volume) override;
+
+private:
+    /// List of streams managed by this sink
+    std::list<SinkStreamPtr> sink_streams{};
+};
+
+} // namespace AudioCore::Sink
diff --git a/src/audio_core/sink/sdl2_sink.cpp b/src/audio_core/sink/sdl2_sink.cpp
index 96e0efce2..7dd155ff0 100644
--- a/src/audio_core/sink/sdl2_sink.cpp
+++ b/src/audio_core/sink/sdl2_sink.cpp
@@ -168,8 +168,9 @@ SDLSink::SDLSink(std::string_view target_device_name) {
 
 SDLSink::~SDLSink() = default;
 
-SinkStream* SDLSink::AcquireSinkStream(Core::System& system, u32 system_channels,
+SinkStream* SDLSink::AcquireSinkStream(Core::System& system, u32 system_channels_,
                                        const std::string&, StreamType type) {
+    system_channels = system_channels_;
     SinkStreamPtr& stream = sink_streams.emplace_back(std::make_unique<SDLSinkStream>(
         device_channels, system_channels, output_device, input_device, type, system));
     return stream.get();
diff --git a/src/audio_core/sink/sink.h b/src/audio_core/sink/sink.h
index f28c6d126..e22e8c3e5 100644
--- a/src/audio_core/sink/sink.h
+++ b/src/audio_core/sink/sink.h
@@ -85,9 +85,21 @@ public:
      */
     virtual void SetSystemVolume(f32 volume) = 0;
 
+    /**
+     * Get the number of channels the game has set, can be different to the host hardware's support.
+     * Either 2 or 6.
+     *
+     * @return Number of device channels.
+     */
+    u32 GetSystemChannels() const {
+        return system_channels;
+    }
+
 protected:
     /// Number of device channels supported by the hardware
     u32 device_channels{2};
+    /// Number of channels the game is sending
+    u32 system_channels{2};
 };
 
 using SinkPtr = std::unique_ptr<Sink>;
diff --git a/src/audio_core/sink/sink_details.cpp b/src/audio_core/sink/sink_details.cpp
index 7c9a4e3ac..449af659d 100644
--- a/src/audio_core/sink/sink_details.cpp
+++ b/src/audio_core/sink/sink_details.cpp
@@ -7,6 +7,9 @@
 #include <vector>
 
 #include "audio_core/sink/sink_details.h"
+#ifdef HAVE_OBOE
+#include "audio_core/sink/oboe_sink.h"
+#endif
 #ifdef HAVE_CUBEB
 #include "audio_core/sink/cubeb_sink.h"
 #endif
@@ -36,6 +39,16 @@ struct SinkDetails {
 
 // sink_details is ordered in terms of desirability, with the best choice at the top.
 constexpr SinkDetails sink_details[] = {
+#ifdef HAVE_OBOE
+    SinkDetails{
+        Settings::AudioEngine::Oboe,
+        [](std::string_view device_id) -> std::unique_ptr<Sink> {
+            return std::make_unique<OboeSink>();
+        },
+        [](bool capture) { return std::vector<std::string>{"Default"}; },
+        []() { return true; },
+    },
+#endif
 #ifdef HAVE_CUBEB
     SinkDetails{
         Settings::AudioEngine::Cubeb,
diff --git a/src/audio_core/sink/sink_stream.cpp b/src/audio_core/sink/sink_stream.cpp
index 2a09db599..c047b0668 100644
--- a/src/audio_core/sink/sink_stream.cpp
+++ b/src/audio_core/sink/sink_stream.cpp
@@ -40,29 +40,36 @@ void SinkStream::AppendBuffer(SinkBuffer& buffer, std::span<s16> samples) {
 
     if (system_channels == 6 && device_channels == 2) {
         // We're given 6 channels, but our device only outputs 2, so downmix.
-        static constexpr std::array<f32, 4> down_mix_coeff{1.0f, 0.707f, 0.251f, 0.707f};
+        // Front = 1.0
+        // Center = 0.596
+        // LFE = 0.354
+        // Back = 0.707
+        static constexpr std::array<f32, 4> down_mix_coeff{1.0, 0.596f, 0.354f, 0.707f};
 
         for (u32 read_index = 0, write_index = 0; read_index < samples.size();
              read_index += system_channels, write_index += device_channels) {
+            const auto fl =
+                static_cast<f32>(samples[read_index + static_cast<u32>(Channels::FrontLeft)]);
+            const auto fr =
+                static_cast<f32>(samples[read_index + static_cast<u32>(Channels::FrontRight)]);
+            const auto c =
+                static_cast<f32>(samples[read_index + static_cast<u32>(Channels::Center)]);
+            const auto lfe =
+                static_cast<f32>(samples[read_index + static_cast<u32>(Channels::LFE)]);
+            const auto bl =
+                static_cast<f32>(samples[read_index + static_cast<u32>(Channels::BackLeft)]);
+            const auto br =
+                static_cast<f32>(samples[read_index + static_cast<u32>(Channels::BackRight)]);
+
             const auto left_sample{
-                ((Common::FixedPoint<49, 15>(
-                      samples[read_index + static_cast<u32>(Channels::FrontLeft)]) *
-                      down_mix_coeff[0] +
-                  samples[read_index + static_cast<u32>(Channels::Center)] * down_mix_coeff[1] +
-                  samples[read_index + static_cast<u32>(Channels::LFE)] * down_mix_coeff[2] +
-                  samples[read_index + static_cast<u32>(Channels::BackLeft)] * down_mix_coeff[3]) *
-                 volume)
-                    .to_int()};
+                static_cast<s32>((fl * down_mix_coeff[0] + c * down_mix_coeff[1] +
+                                  lfe * down_mix_coeff[2] + bl * down_mix_coeff[3]) *
+                                 volume)};
 
             const auto right_sample{
-                ((Common::FixedPoint<49, 15>(
-                      samples[read_index + static_cast<u32>(Channels::FrontRight)]) *
-                      down_mix_coeff[0] +
-                  samples[read_index + static_cast<u32>(Channels::Center)] * down_mix_coeff[1] +
-                  samples[read_index + static_cast<u32>(Channels::LFE)] * down_mix_coeff[2] +
-                  samples[read_index + static_cast<u32>(Channels::BackRight)] * down_mix_coeff[3]) *
-                 volume)
-                    .to_int()};
+                static_cast<s32>((fr * down_mix_coeff[0] + c * down_mix_coeff[1] +
+                                  lfe * down_mix_coeff[2] + br * down_mix_coeff[3]) *
+                                 volume)};
 
             samples[write_index + static_cast<u32>(Channels::FrontLeft)] =
                 static_cast<s16>(std::clamp(left_sample, min, max));