- enforce locking before getting.

- explicitly keep track of last now time to determine max delta.
- refactoring.


git-svn-id: https://gambatte.svn.sourceforge.net/svnroot/gambatte@306 9dfb2916-2d38-0410-aef4-c5fe6c9ffc24

gambatte_qt/src/framework/src/mainwindow.cpp

@@ -24,10 +24,8 @@
 #include <QtGlobal> // for Q_WS_WIN define
 
 MainWindow::FrameBuffer::Locked::Locked(FrameBuffer fb) : mw(0), pb() {
-	if (fb.mw->tryLockFrameBuf()) {
+	if (fb.mw->tryLockFrameBuf(pb))
 		mw = fb.mw;
-		pb = fb.mw->frameBuf();
-	}
 }
 
 MainWindow::FrameBuffer::Locked::~Locked() {

gambatte_qt/src/framework/src/mediawidget.cpp

@@ -19,6 +19,7 @@
 #include "mediawidget.h"
 #include <QEvent>
 #include <QKeyEvent>
+#include <QMutexLocker>
 #include <QCoreApplication>
 #include <QtGlobal> // for Q_WS_WIN define
 #include "adaptivesleep.h"
@@ -130,11 +131,17 @@ public:
 	bool cancelBlit();
 	void paused();
 	void audioEngineFailure();
-	bool tryLockVideoBuffer() { return mw.vbmut.tryLock(); }
-	void unlockVideoBuffer() { mw.vbmut.unlock(); }
-	const PixelBuffer& videoBuffer() {
-		return mw.blitterContainer->blitter()->inBuffer();
+	
+	bool tryLockVideoBuffer(PixelBuffer &pb) {
+		if (mw.vbmut.tryLock()) {
+			pb = mw.blitterContainer->blitter()->inBuffer();
+			return true;
+		}
+		
+		return false;
 	}
+	
+	void unlockVideoBuffer() { mw.vbmut.unlock(); }
 
 	void consumeBlitRequest();
 };
@@ -364,13 +371,13 @@ void MediaWidget::setBlitter(BlitterWidget *const blitter) {
 
 void MediaWidget::setVideo(const unsigned w, const unsigned h, BlitterWidget *const blitter) {
 	if (QSize(w, h) != blitterContainer->sourceSize() || blitter != blitterContainer->blitter()) {
-		vbmut.lock();
-		setBlitter(blitter);
+		{
+			const QMutexLocker vblock(&vbmut);
+			setBlitter(blitter);
 
-		if (running)
-			blitterContainer->blitter()->setVideoFormat(w, h);
-
-		vbmut.unlock();
+			if (running)
+				blitterContainer->blitter()->setVideoFormat(w, h);
+		}
 		
 		blitterContainer->setSourceSize(QSize(w, h));
 	}

gambatte_qt/src/framework/src/mediawidget.h

@@ -120,9 +120,16 @@ public:
 	void keyPressEvent(QKeyEvent*);
 	void keyReleaseEvent(QKeyEvent*);
 	
-	bool tryLockFrameBuf() { return vbmut.tryLock(); }
+	bool tryLockFrameBuf(PixelBuffer &pb) {
+		if (vbmut.tryLock()) {
+			pb = running ? blitterContainer->blitter()->inBuffer() : PixelBuffer();
+			return true;
+		}
+		
+		return false;
+	}
+	
 	void unlockFrameBuf() { vbmut.unlock(); }
-	const PixelBuffer frameBuf() const { return running ? blitterContainer->blitter()->inBuffer() : PixelBuffer(); }
 	
 	const QSize& videoSize() const { return blitterContainer->sourceSize(); }
 	

gambatte_qt/src/framework/src/mediaworker.cpp

@@ -311,11 +311,9 @@ long MediaWorker::sourceUpdate() {
 		Callback *cb;
 		PixelBuffer pb;
 	public:
-		VidBuf(Callback *cb) : cb(cb), pb(cb->videoBuffer()) {
-			if (!cb->tryLockVideoBuffer()) {
-				pb.data = 0;
+		explicit VidBuf(Callback *cb) : cb(cb), pb() {
+			if (!cb->tryLockVideoBuffer(pb))
 				this->cb = 0;
-			}
 		}
 
 		~VidBuf() { if (cb) cb->unlockVideoBuffer(); }
@@ -335,23 +333,29 @@ void MediaWorker::adjustResamplerRate(const long outRate) {
 		sndOutBuffer.reset(sz);
 }
 
-static usec_t frameWait(const usec_t base, const usec_t syncft, const usec_t usecsFromUnderrun, SyncVar &waitingForSync) {
-	const usec_t now = getusecs();
+namespace {
+struct NowDelta { usec_t now, inc;
+                  NowDelta(usec_t now, usec_t inc) : now(now), inc(inc) {} };
+}
 
-	if (base + syncft - now < syncft * 2) {
-		if (base + syncft - now >= usecsFromUnderrun - (usecsFromUnderrun >> 2))
-			return base;
+static const NowDelta frameWait(const NowDelta basetime,
+		const usec_t syncft, const usec_t usecsFromUnderrun, SyncVar &waitingForSync) {
+	const usec_t now = getusecs();
+	const usec_t target = basetime.now + basetime.inc + syncft;
+	
+	if (target - now < basetime.inc + syncft) {
+		if (target - now >= usecsFromUnderrun - (usecsFromUnderrun >> 2))
+			return basetime;
 		
 		SyncVar::Locked wfs(waitingForSync);
-
-		/*while*/if (!wfs.get() && /*wfs.wait(now, base + syncft - now)*/ wfs.wait((base + syncft - now) / 1000)) {
-			;
-		}
-
-		return base + syncft;
+		
+		if (!wfs.get())
+			wfs.wait((target - now) / 1000);
+		
+		return NowDelta(now, target - now);
 	}
-
-	return now;
+	
+	return NowDelta(now, 0);
 }
 
 static void blitWait(MediaWorker::Callback *const cb, SyncVar &waitingForSync) {
@@ -410,7 +414,7 @@ void MediaWorker::run() {
 
 	SkipSched skipSched;
 	bool audioBufLow = false;
-	usec_t base = 0;
+	NowDelta basetime(0, 0);
 
 	for (;;) {
 		pauseVar.waitWhilePaused(callback.get(), *ao_);
@@ -428,7 +432,7 @@ void MediaWorker::run() {
 			const bool blit   = blitSamples >= 0 && !skipSched.skipNext(audioBufLow);
 
 			if (blit)
-				callback->blit(base, syncft);
+				callback->blit(basetime.now, basetime.inc + syncft);
 
 			const long outsamples = sampleBuffer.read(
 					blit ? blitSamples : sampleBuffer.samplesBuffered(),
@@ -446,7 +450,8 @@ void MediaWorker::run() {
 			audioBufLow = audioBufIsLow(bstate, outsamples);
 
 			if (blit) {
-				base = frameWait(base, syncft, usecsFromUnderrun(bstate, outsamples, ao_->estimatedRate()), waitingForSync_);
+				basetime = frameWait(basetime, syncft, usecsFromUnderrun(
+						bstate, outsamples, ao_->estimatedRate()), waitingForSync_);
 				blitWait(callback.get(), waitingForSync_);
 			}
 		}

gambatte_qt/src/framework/src/mediaworker.h

@@ -40,9 +40,8 @@ public:
 		virtual bool cancelBlit() = 0;
 // 		virtual void sync() = 0;
 		virtual void audioEngineFailure() = 0;
-		virtual bool tryLockVideoBuffer() = 0;
+		virtual bool tryLockVideoBuffer(PixelBuffer &pb) = 0;
 		virtual void unlockVideoBuffer() = 0;
-		virtual const PixelBuffer& videoBuffer() = 0;
 		virtual ~Callback() {}
 	};