_ak_f_x_tail_handler_8h

Wwise SDK 2023.1.3

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 released in source code form as part of the SDK installer package.
  
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 #ifndef _AKFXTAILHANDLER_H_
 #define _AKFXTAILHANDLER_H_
  
 #include <AK/SoundEngine/Common/AkTypes.h>
 #include <AK/SoundEngine/Common/AkCommonDefs.h>
 #include <AK/Tools/Common/AkPlatformFuncs.h>
  
 /// Default value when effect has not enterred tail mode yet.
 #define AKFXTAILHANDLER_NOTINTAIL 0xFFFFFFFF
  
 /// Effect tail handling utility class.
 /// Handles varying number of tail frames from frame to frame (i.e. based on RTPC parameters).
 /// Handles effect revived (quit tail) and reenters etc.
 class AkFXTailHandler
 {
 public:
     /// Constructor
     inline AkFXTailHandler() 
         : uTailFramesRemaining( AKFXTAILHANDLER_NOTINTAIL )
         , uTotalTailFrames(0) {}
  
     /// Handle FX tail and zero pads AkAudioBuffer if necessary
     inline void HandleTail( 
         AkAudioBuffer * io_pBuffer, 
         AkUInt32 in_uTotalTailFrames )
     {
         bool bPreStop = io_pBuffer->eState == AK_NoMoreData;
         if ( bPreStop )
         {   
             // Tail not yet finished processing
             if ( uTailFramesRemaining > 0  
                 || io_pBuffer->uValidFrames > 0 // <-- there are valid frames, so last (maybe partially filled) buffer.
                 )
             {
                 // Not previously in tail, compute tail time
                 if (uTailFramesRemaining == AKFXTAILHANDLER_NOTINTAIL  
                     || io_pBuffer->uValidFrames > 0 // <- ANY valid frames in the buffer should reset the tail.
                     )
                 {
                     uTailFramesRemaining = in_uTotalTailFrames;
                     uTotalTailFrames     = in_uTotalTailFrames;
                 }
                 // Tail time changed, augment if necessary but preserve where we are so that effect will 
                 // still finish when constantly changing this based on RTPC parameters
                 else if ( in_uTotalTailFrames > uTotalTailFrames )
                 {
                     AkUInt32 uFramesElapsed = uTotalTailFrames - uTailFramesRemaining;
                     uTailFramesRemaining = in_uTotalTailFrames - uFramesElapsed;
                     uTotalTailFrames     = in_uTotalTailFrames;
                 }
                 // Always full buffers while in tail
                 AkUInt32 uNumTailFrames = (AkUInt32)(io_pBuffer->MaxFrames()-io_pBuffer->uValidFrames); 
                 uTailFramesRemaining -= AkMin( uTailFramesRemaining, uNumTailFrames ); 
                 io_pBuffer->ZeroPadToMaxFrames();
                 if ( uTailFramesRemaining > 0 )
                     io_pBuffer->eState = AK_DataReady;
             }
         }
         else
         {
             // Reset tail mode for next time if exits tail mode (on bus only)
             uTailFramesRemaining = AKFXTAILHANDLER_NOTINTAIL;
         }
     }
  
     inline bool HasTailRemaining() { return uTailFramesRemaining > 0; } // Also true when AKFXTAILHANDLER_NOTINTAIL
  
 protected:
  
     AkUInt32    uTailFramesRemaining; // AKFXTAILHANDLER_NOTINTAIL, otherwise value represents number of frames remaining in tail
     AkUInt32    uTotalTailFrames;
     
 };
  
  
  
  
  
 #endif // _AKFXTAILHANDLER_H_