AudioMixerPlatformAndroid.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
 
#pragma once
 
#include "AudioMixer.h"
#include "DSP/Dsp.h"
#include <SLES/OpenSLES.h>
#include "SLES/OpenSLES_Android.h"
 
// Any platform defines
namespace Audio
{
 
    class FMixerPlatformAndroid : public IAudioMixerPlatformInterface
    {
 
    public:
 
        FMixerPlatformAndroid();
        ~FMixerPlatformAndroid();
 
        //~ Begin IAudioMixerPlatformInterface
        virtual FString GetPlatformApi() const override { return TEXT("OpenSLES"); }
        virtual bool InitializeHardware() override;
        virtual bool TeardownHardware() override;
        virtual bool IsInitialized() const override;
        virtual bool GetNumOutputDevices(uint32& OutNumOutputDevices) override;
        virtual bool GetOutputDeviceInfo(const uint32 InDeviceIndex, FAudioPlatformDeviceInfo& OutInfo) override;
        virtual bool GetDefaultOutputDeviceIndex(uint32& OutDefaultDeviceIndex) const override;
        virtual bool OpenAudioStream(const FAudioMixerOpenStreamParams& Params) override;
        virtual bool CloseAudioStream() override;
        virtual bool StartAudioStream() override;
        virtual bool StopAudioStream() override;
        virtual FAudioPlatformDeviceInfo GetPlatformDeviceInfo() const override;
        virtual void SubmitBuffer(const uint8* Buffer) override;
        virtual FString GetDefaultDeviceName() override;
        virtual FAudioPlatformSettings GetPlatformSettings() const override;
        virtual void SuspendContext() override;
        virtual void ResumeContext() override;
 
        //~ End IAudioMixerPlatformInterface
        
    private:
        const TCHAR* GetErrorString(SLresult Result);
 
        int32 GetDeviceBufferSize(int32 RenderCallbackSize) const;
 
        SLObjectItf SL_EngineObject;
        SLEngineItf SL_EngineEngine;
        SLObjectItf SL_OutputMixObject;
        SLObjectItf SL_PlayerObject;
        SLPlayItf SL_PlayerPlayInterface;
        SLAndroidSimpleBufferQueueItf SL_PlayerBufferQueue;
 
        FCriticalSection SuspendedCriticalSection;
 
        bool bSuspended;
        bool bInitialized;
        bool bInCallback;
        
        // This buffer is pushed to and popped from in the SubmitBuffer callback. 
        // This is required for devices that require frame counts per callback that are not powers of two.
        Audio::TCircularAudioBuffer<int16> CircularOutputBuffer;
 
        // This is the buffer we pop CircularOutputBuffer into in SubmitBuffer.
        TArray<int16> DeviceBuffer;
 
        int32 NumSamplesPerRenderCallback;
        int32 NumSamplesPerDeviceCallback;
 
        static void OpenSLBufferQueueCallback( SLAndroidSimpleBufferQueueItf InQueueInterface, void* pContext );        
    };
 
}