tetrees/Plugins/Wwise/ThirdParty/include/AK/SoundEngine/Common/IAkMixerPlugin.h

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/// \file 
/// Software source plug-in and effect plug-in interfaces.

#ifndef _IAK_MIXER_PLUGIN_H_
#define _IAK_MIXER_PLUGIN_H_

#include <AK/SoundEngine/Common/IAkPlugin.h>

namespace AK
{
	/// Software effect plug-in interface for panner/mixer effects (see \ref soundengine_plugins_effects).
	class IAkMixerEffectPlugin : public IAkPlugin
	{
	public:

		/// Software effect plug-in initialization. Prepares the effect for data processing, allocates memory and sets up the initial conditions. 
		/// \aknote Memory allocation should be done through appropriate macros (see \ref fx_memory_alloc). \endaknote
		virtual AKRESULT Init( 
			IAkPluginMemAlloc *			in_pAllocator,				///< Interface to memory allocator to be used by the effect.
			IAkMixerPluginContext *		in_pMixerPluginContext,		///< Interface to mixer plug-in's context.
			IAkPluginParam *			in_pParams,					///< Interface to plug-in parameters.
			AkAudioFormat &				in_rFormat					///< Audio data format of the requested output signal.
			) = 0;

		/// This function is called whenever a new input is connected to the underlying mixing bus.
		virtual void OnInputConnected( 
			IAkMixerInputContext * in_pInput			///< Input that is being connected.
			) = 0;
		
		/// This function is called whenever a new input is disconnected to the underlying mixing bus.
		/// \aknote OnInputDisconnected() may be called between calls to ConsumeInput() and OnMixDone().\endaknote
		virtual void OnInputDisconnected( 
			IAkMixerInputContext * in_pInput			///< Input that is being disconnected.
			) = 0;

		/// This function is called whenever an input (voice or bus) needs to be mixed.
		/// During an audio frame, ConsumeInput() will be called for each input that need to be mixed.
		/// \aknote io_pInputBuffer->eState will be set as AK_NoMoreData the last time the given input is processed by ConsumeInput(). Otherwise it is set to AK_DataReady.
		/// Mixers cannot make an input remain alive by changing their state.\endaknote
		/// \aknote ConsumeInput() will not be called for frames during which a voice is not audible.\endaknote
		/// \sa
		/// - OnMixDone
		/// - OnEffectsProcessed
		virtual void ConsumeInput( 
			IAkMixerInputContext *	in_pInputContext,	///< Context for this input. Carries non-audio data.
			AkRamp					in_baseVolume,		///< Base volume to apply to this input (prev corresponds to the beginning, next corresponds to the end of the buffer). This gain is agnostic of emitter-listener pair-specific contributions (such as distance level attenuation).
			AkRamp					in_emitListVolume,	///< Emitter-listener pair-specific gain. When there are multiple emitter-listener pairs, this volume equals 1, and pair gains are applied directly on the channel volume matrix (accessible via IAkMixerInputContext::GetSpatializedVolumes()). For custom processing of emitter-listener pairs, one should query each pair volume using IAkMixerInputContext::Get3DPosition(), then AkEmitterListenerPair::GetGainForConnectionType().
			AkAudioBuffer *			io_pInputBuffer,	///< Input audio buffer data structure. Plugins should avoid processing data in-place.
			AkAudioBuffer *			io_pMixBuffer		///< Output audio buffer data structure. Stored until call to OnEffectsProcessed().
			) = 0;

		/// This function is called once every audio frame, when all inputs have been mixed in 
		/// with ConsumeInput(). It is the time when the plugin may perform final DSP/bookkeeping.
		/// After the bus buffer io_pMixBuffer has been pushed to the bus downstream (or the output device),
		/// it is cleared out for the next frame.
		/// \aknote io_pMixBuffer->eState is passed as AK_DataReady for the whole existence of the bus, until the last frame where it will be set to AK_NoMoreData.
		/// However, mixer plugins are capable of forcing the bus to remain alive for a longer time by changing io_pMixBuffer->eState back to AK_DataReady.
		/// You may do this in OnMixDone() or in OnEffectsProcessed(). The difference is that effects inserted on the bus will enter their "tail mode" if you
		/// wait until OnEffectsProcessed() to flip the state to AK_DataReady. This is usually undesirable, so handling this inside OnMixDone() is usually preferred.\endaknote
		/// \sa
		/// - ConsumeInput
		/// - OnEffectsProcessed
		virtual void OnMixDone( 
			AkAudioBuffer *			io_pMixBuffer		///< Output audio buffer data structure. Stored across calls to ConsumeInput().
			) = 0;

		/// This function is called once every audio frame, after all insert effects on the bus have been processed, 
		/// which occur after the post mix pass of OnMixDone().
		/// After the bus buffer io_pMixBuffer has been pushed to the bus downstream (or the output device),
		/// it is cleared out for the next frame.
		/// \aknote io_pMixBuffer->eState is passed as AK_DataReady for the whole existence of the bus, until the last frame where it will be set to AK_NoMoreData.
		/// However, mixer plugins are capable of forcing the bus to remain alive for a longer time by changing io_pMixBuffer->eState back to AK_DataReady.
		/// You may do this in OnMixDone(), in OnEffectsProcessed() or in OnFrameEnd(). The difference is that effects inserted on the bus will enter their "tail mode" if you
		/// wait until OnEffectsProcessed() or OnFrameEnd() to flip the state to AK_DataReady. This is usually undesirable, so handling this inside OnMixDone() is usually preferred.\endaknote
		/// \sa
		/// - OnMixDone
		/// - AK::AkMetering
		/// - AK::IAkMixerPluginContext::EnableMetering()
		virtual void OnEffectsProcessed( 
			AkAudioBuffer *			io_pMixBuffer		///< Output audio buffer data structure.
			) = 0;

		/// This function is called once every audio frame, after all insert effects on the bus have been processed, and after metering has been processed (if applicable),
		/// which occur after OnEffectsProcessed().
		/// After the bus buffer io_pMixBuffer has been pushed to the bus downstream (or the output device), it is cleared out for the next frame.
		/// Mixer plugins may use this hook for processing the signal after it has been metered.
		/// \aknote io_pMixBuffer->eState is passed as AK_DataReady for the whole existence of the bus, until the last frame where it will be set to AK_NoMoreData.
		/// However, mixer plugins are capable of forcing the bus to remain alive for a longer time by changing io_pMixBuffer->eState back to AK_DataReady.
		/// You may do this in OnMixDone(), in OnEffectsProcessed() or in OnFrameEnd(). The difference is that effects inserted on the bus will enter their "tail mode" if you
		/// wait until OnEffectsProcessed() or OnFrameEnd() to flip the state to AK_DataReady. This is usually undesirable, so handling this inside OnMixDone() is usually preferred.\endaknote
		/// \aknote This function is called after metering gets computed on io_pMixBuffer. You may access the result in in_pMetering. Metering has to be enabled with AK::IAkMixerPluginContext::EnableMetering().
		/// It may also be enabled by the Wwise authoring tool when connected.\endaknote
		/// \sa
		/// - OnMixDone
		/// - AK::AkMetering
		/// - AK::IAkMixerPluginContext::EnableMetering()
		virtual void OnFrameEnd(
			AkAudioBuffer *			io_pMixBuffer,		///< Output audio buffer data structure.
			AkMetering *			in_pMetering		///< Struct containing metering data computed on io_pMixBuffer. May be NULL if metering is not enabled.
			) = 0;
	};
}
#endif // _IAK_MIXER_PLUGIN_H_