distinguish between end of stream and end of data

svn-id: r11756

sound/audiostream.cpp

@@ -82,7 +82,7 @@ public:
 		return val;
 	}
 	bool isStereo() const		{ return stereo; }
-	bool eos() const			{ return eosIntern(); }
+	bool endOfData() const		{ return eosIntern(); }
 
 	int getRate() const			{ return _rate; }
 };
@@ -131,7 +131,8 @@ public:
 
 	int16 read();
 	bool isStereo() const		{ return stereo; }
-	bool eos() const			{ return _finalized && eosIntern(); }
+	bool endOfStream() const	{ return _finalized && eosIntern(); }
+	bool endOfData() const		{ return eosIntern(); }
 
 	int getRate() const			{ return _rate; }
 
@@ -276,7 +277,7 @@ public:
 		return *_pos++;
 	}
 	bool isStereo() const { return _isStereo; }
-	bool eos() const { return false; }
+	bool endOfData() const { return false; }
 	
 	int getRate() const { return _rate; }
 };

sound/audiostream.h

@@ -53,8 +53,24 @@ public:
 	/** Is this a stereo stream? */
 	virtual bool isStereo() const = 0;
 	
-	/** End of stream reached? */
-	virtual bool eos() const = 0;
+	/**
+	 * End of data reached? If this returns true, it means that at this
+	 * time there is no data available in the stream. However there may be
+	 * more data in the future.
+	 * This is used by e.g. a rate converter to decide whether to keep on
+	 * converting data or stop.
+	 */
+	virtual bool endOfData() const = 0;
+	
+	/**
+	 * End of stream reached? If this returns true, it means that all data
+	 * in this stream is used up and no additional data will appear in it
+	 * in the future.
+	 * This is used by the mixer to decide whether a given stream shall be
+	 * removed from the list of active streams (and thus be destroyed).
+	 * By default this maps to endOfData()
+	 */
+	virtual bool endOfStream() const { return endOfData(); }
 
 	/** Sample rate of the stream. */
 	virtual int getRate() const = 0;

sound/mixer.cpp

@@ -485,9 +485,11 @@ void Channel::destroy() {
  */
 void Channel::mix(int16 *data, uint len) {
 	assert(_input);
-	if (_input->eos()) {
-		// TODO: call drain method
+
+	if (_input->endOfStream()) {
 		destroy();
+	} else if (_input->endOfData()) {
+		// TODO: call drain method
 	} else {
 		assert(_converter);
 

sound/mp3.cpp

@@ -152,7 +152,7 @@ public:
 	int readBuffer(int16 *buffer, const int numSamples);
 
 	int16 read();
-	bool eos() const			{ return eosIntern(); }
+	bool endOfData() const		{ return eosIntern(); }
 	bool isStereo() const		{ return _isStereo; }
 	
 	int getRate() const			{ return _frame.header.samplerate; }

sound/rate.cpp

@@ -200,7 +200,7 @@ public:
 		int16 tmp[2];
 		st_size_t len = osamp;
 		assert(input.isStereo() == stereo);
-		while (!input.eos() && len--) {
+		while (!input.endOfData() && len--) {
 			tmp[0] = tmp[1] = input.read();
 			if (stereo)
 				tmp[reverseStereo ? 0 : 1] = input.read();

sound/vorbis.cpp

@@ -166,7 +166,7 @@ public:
 	int readBuffer(int16 *buffer, const int numSamples);
 
 	int16 read();
-	bool eos() const			{ return eosIntern(); }
+	bool endOfData() const		{ return eosIntern(); }
 	bool isStereo() const		{ return _numChannels >= 2; }
 	
 	int getRate() const			{ return ov_info(_ov_file, -1)->rate; }

sword2/driver/d_sound.cpp

@@ -105,7 +105,7 @@ int16 MusicHandle::read() {
 	return out;
 }
 
-bool MusicHandle::eos() const {
+bool MusicHandle::endOfData() const {
 	return (!_streaming || _filePos >= _fileEnd);
 }
 

sword2/driver/d_sound.h

@@ -61,14 +61,16 @@ public:
 
 	virtual int readBuffer(int16 *buffer, const int numSamples) {
 		int samples;
-		for (samples = 0; samples < numSamples && !eos(); samples++) {
+		for (samples = 0; samples < numSamples && !endOfData(); samples++) {
 			*buffer++ = read();
 		}
 		return samples;
 	}
 
 	int16 read();
-	bool eos() const;
+	bool endOfData() const;
+	// This stream never 'ends'
+	bool endOfStream() const { return false; }
 
 	MusicHandle() : _firstTime(false),
 			_streaming(false), _paused(false), _looping(false),