TITANIC: Match the CWaveFile duration method closer to original

3 files changed, 17 insertions, 6 deletions

diff --git a/engines/titanic/sound/sound.cpp b/engines/titanic/sound/sound.cpp
index a8c4849f2b..e48c8760c5 100644
--- a/engines/titanic/sound/sound.cpp
+++ b/engines/titanic/sound/sound.cpp
@@ -159,7 +159,7 @@ int CSound::playSound(const CString &name, CProximity &prox) {
 	if (!waveFile)
 		return -1;
 
-	prox._soundDuration = waveFile->getDuration();
+	prox._soundDuration = waveFile->getDurationTicks();
 	if (prox._soundType != Audio::Mixer::kPlainSoundType)
 		waveFile->_soundType = prox._soundType;
 
@@ -209,7 +209,7 @@ int CSound::playSpeech(CDialogueFile *dialogueFile, int speechId, CProximity &pr
 	if (!waveFile)
 		return -1;
 
-	prox._soundDuration = waveFile->getDuration();
+	prox._soundDuration = waveFile->getDurationTicks();
 	activateSound(waveFile, prox._disposeAfterUse);
 
 	return _soundManager.playSound(*waveFile, prox);
diff --git a/engines/titanic/sound/wave_file.cpp b/engines/titanic/sound/wave_file.cpp
index 3f855cd053..ade94aad50 100644
--- a/engines/titanic/sound/wave_file.cpp
+++ b/engines/titanic/sound/wave_file.cpp
@@ -43,8 +43,17 @@ CWaveFile::~CWaveFile() {
 	}
 }
 
-uint CWaveFile::getDuration() const {
-	return _stream ? _stream->getLength().secs() : 0;
+uint CWaveFile::getDurationTicks() const {
+	if (!_stream)
+		return 0;
+
+	// FIXME: The original uses acmStreamSize to calculate
+	// a desired size. Since I have no idea how the system API
+	// method works, for now I'm using a simple ratio of a
+	// sample output to input value
+	uint size = _size - 0x46;
+	double newSize = (double)size * (1475712.0 / 199836.0);
+	return newSize * 1000.0 / _stream->getRate();
 }
 
 bool CWaveFile::loadSound(const CString &name) {
diff --git a/engines/titanic/sound/wave_file.h b/engines/titanic/sound/wave_file.h
index 4237f1a203..19d367936f 100644
--- a/engines/titanic/sound/wave_file.h
+++ b/engines/titanic/sound/wave_file.h
@@ -46,9 +46,11 @@ public:
 	~CWaveFile();
 
 	/**
-	 * Returns the duration of the wave file in seconds
+	 * Returns the duration of the wave file
+	 * @returns	Total ticks. Not really sure how ticks
+	 * map to real time
 	 */
-	uint getDuration() const;
+	uint getDurationTicks() const;
 
 	/**
 	 * Return the size of the wave file