From 554c60ea89a9e27438b81212b649327773a89fa8 Mon Sep 17 00:00:00 2001
From: Bartosz Taudul <wolf.pld@gmail.com>
Date: Sat, 15 Nov 2008 22:10:00 +0100
Subject: [PATCH] Crackle-free audio playback.

Provide flawless audio playback by removing stupid and things-breaking
delays. Current implementation uses 10s timer that is cancelled when
next audio sample is needed to provide mutex-like logic for active
scheduler instead of calculating some never-correct wait times.
---
 src/audio/symbian/SDL_epocaudio.cpp | 31 ++-----------------------------
 1 file changed, 2 insertions(+), 29 deletions(-)

diff --git a/src/audio/symbian/SDL_epocaudio.cpp b/src/audio/symbian/SDL_epocaudio.cpp
index b5bf1b9..f7346ce 100644
--- a/src/audio/symbian/SDL_epocaudio.cpp
+++ b/src/audio/symbian/SDL_epocaudio.cpp
@@ -65,7 +65,6 @@ class CSimpleWait : public CTimer
 {
 	public:
 		CSimpleWait();
-		void Wait(TTimeIntervalMicroSeconds32 aWait);
 
 	private:
 		void RunL();
@@ -78,12 +77,6 @@ CSimpleWait::CSimpleWait()
 	ConstructL();
 }
 
-void CSimpleWait::Wait(TTimeIntervalMicroSeconds32 aWait)
-{
-	After(aWait);
-	CActiveScheduler::Start();
-}
-
 void CSimpleWait::RunL()
 {
 	CActiveScheduler::Stop();
@@ -100,7 +93,6 @@ class CEpocAudio : public CBase, public MStreamObs, public MStreamProvider
 		static void Free(SDL_AudioDevice* thisdevice);
 
 		void Wait();
-		void Play();
 		void ThreadInitL();
 		TUint8* Buffer();
 
@@ -114,7 +106,6 @@ class CEpocAudio : public CBase, public MStreamObs, public MStreamProvider
 		TUint32 iType;
 		int iBufferSize;
 		TUint8* iBuffer;
-		TTime iStart;
 		CSimpleWait* iWait;
 };
 
@@ -177,7 +168,6 @@ void CEpocAudio::ThreadInitL()
 
 TUint8* CEpocAudio::Buffer()
 {
-	iStart.UniversalTime();
 	return iBuffer;
 }
 
@@ -210,27 +200,11 @@ TPtrC8 CEpocAudio::Data()
 	return data;
 }
 
-void CEpocAudio::Play()
-{
-}
-
 void CEpocAudio::Wait()
 {
-	const TInt64 bufMs = TInt64(iBufferSize) * TInt64(1000000);
-	const TInt64 specTime =  bufMs / TInt64(iRate * iChannels * 2);
-	iWait->After(specTime);
-
+	// This wait will be terminated by call to Data() from audio buffer callback.
+	iWait->After(10000000);
 	CActiveScheduler::Start();
-	TTime end;
-	end.UniversalTime();
-	const TTimeIntervalMicroSeconds delta = end.MicroSecondsFrom(iStart);
-
-	const int diff = specTime - delta.Int64();
-
-	if(diff > 0)
-	{
-		usleep(diff);
-	}
 }
 
 /* Audio driver bootstrap functions */
@@ -355,7 +329,6 @@ static void EPOC_WaitAudio(SDL_AudioDevice* thisdevice)
 
 static void EPOC_PlayAudio(SDL_AudioDevice* thisdevice)
 {
-	CEpocAudio::Current(thisdevice).Play();
 }
 
 static Uint8 *EPOC_GetAudioBuf(SDL_AudioDevice* thisdevice)
-- 
2.11.4.GIT