Make a clear separation between loading a sound file into main memroy and sending it to the driver. This prevents data to be loaded into the main memory (or onto the soundcard's memory) when it's not needed.

simgear/sound/openal_test2.cxx

@@ -14,37 +14,37 @@ static unsigned int sleep(unsigned int secs) { return 0; }
 int main( int argc, char *argv[] ) {
     SGSoundMgr sm;
 
-    SGSoundSample sample1( ".", "jet.wav", true );
+    SGSoundSample sample1( ".", "jet.wav" );
     sample1.set_volume(0.5);
     sample1.set_volume(0.2);
     sample1.play_looped();
     sleep(1);
 
-    SGSoundSample sample2( ".", "jet.wav", true );
+    SGSoundSample sample2( ".", "jet.wav" );
     sample2.set_volume(0.5);
     sample2.set_pitch(0.4);
     sample2.play_looped();
     sleep(1);
 
-    SGSoundSample sample3( ".", "jet.wav", true );
+    SGSoundSample sample3( ".", "jet.wav" );
     sample3.set_volume(0.5);
     sample3.set_pitch(0.8);
     sample3.play_looped();
     sleep(1);
 
-    SGSoundSample sample4( ".", "jet.wav", true );
+    SGSoundSample sample4( ".", "jet.wav" );
     sample4.set_volume(0.5);
     sample4.set_pitch(1.2);
     sample4.play_looped();
     sleep(1);
 
-    SGSoundSample sample5( ".", "jet.wav", true );
+    SGSoundSample sample5( ".", "jet.wav" );
     sample5.set_volume(0.5);
     sample5.set_pitch(1.6);
     sample5.play_looped();
     sleep(1);
 
-    SGSoundSample sample6( ".", "jet.wav", true );
+    SGSoundSample sample6( ".", "jet.wav" );
     sample6.set_volume(0.5);
     sample6.set_pitch(2.0);
     sample6.play_looped();

simgear/sound/sample_openal.cxx

@@ -63,11 +63,21 @@ static bool print_openal_error(const string &s = "unknown") {
     return error;
 }
 
+// empry constructor
+SGSoundSample::SGSoundSample() :
+    buffer(0),
+    source(0),
+    pitch(1.0),
+    volume(1.0),
+    reference_dist(500.0),
+    max_dist(3000.),
+    loop(AL_FALSE),
+    playing(false)
+{
+}
 
 // constructor
-SGSoundSample::SGSoundSample( const char *path, const char *file,
+SGSoundSample::SGSoundSample( const char *path, const char *file) :
-                              bool cleanup ) :
-    data(NULL),
     buffer(0),
     source(0),
     pitch(1.0),
@@ -81,7 +91,6 @@ SGSoundSample::SGSoundSample( const char *path, const char *file,
     if ( strlen(file) ) {
         samplepath.append( file );
     }
-
     sample_name = samplepath.str();
 
     SG_LOG( SG_GENERAL, SG_DEBUG, "From file sounds sample = "
@@ -116,16 +125,7 @@ SGSoundSample::SGSoundSample( const char *path, const char *file,
         //
 	// pre 1.0 alut version
         //
-# if defined (__APPLE__)
+    ALvoid* data = load_file(path, file)
-    alutLoadWAVFile( (ALbyte *)samplepath.c_str(),
-                     &format, &data, &size, &freq );
-# else
-    alutLoadWAVFile( (ALbyte *)samplepath.c_str(),
-                     &format, &data, &size, &freq, &loop );
-# endif
-    if ( print_openal_error("constructor (alutLoadWAVFile)") ) {
-        throw sg_exception("Failed to load wav file.");
-    }
 
     // Copy data to the internal OpenAL buffer
     alBufferData( buffer, format, data, size, freq );
@@ -134,20 +134,15 @@ SGSoundSample::SGSoundSample( const char *path, const char *file,
         throw sg_exception("Failed to buffer data.");
     }
 
-    if ( cleanup ) {
+    alutUnloadWAV( format, data, size, freq );
-        alutUnloadWAV( format, data, size, freq );
-        data = NULL;
-    }
 #endif
 
     print_openal_error("constructor return");
 }
 
-
 // constructor
 SGSoundSample::SGSoundSample( unsigned char *_data, int len, int _freq,
                               bool cleanup) :
-    data(NULL),
     buffer(0),
     source(0),
     pitch(1.0),
@@ -178,17 +173,15 @@ SGSoundSample::SGSoundSample( unsigned char *_data, int len, int _freq,
 
     format = AL_FORMAT_MONO8;
     size = len;
-    data = _data;
     freq = _freq;
 
-    alBufferData( buffer, format, data, size, freq );
+    alBufferData( buffer, format, _data, size, freq );
     if ( print_openal_error("constructor (alBufferData)") ) {
         throw sg_exception("Failed to buffer data.");
     }
 
     if ( cleanup ) {
-        alutUnloadWAV( format, data, size, freq );
+        free(_data);
-        data = NULL;
     }
 
     print_openal_error("constructor return");
@@ -198,7 +191,8 @@ SGSoundSample::SGSoundSample( unsigned char *_data, int len, int _freq,
 // destructor
 SGSoundSample::~SGSoundSample() {
     SG_LOG( SG_GENERAL, SG_INFO, "Deleting a sample" );
-    alDeleteBuffers(1, &buffer);
+    if (buffer)
+        alDeleteBuffers(1, &buffer);
 }
 
 
@@ -239,6 +233,9 @@ SGSoundSample::bind_source() {
     if ( playing ) {
         return true;
     }
+    if ( buffer == 0 ) {
+        return false;
+    }
 
     // Bind buffer with a source.
     alGetError();
@@ -376,3 +373,37 @@ SGSoundSample::set_max_dist( ALfloat dist ) {
         alSourcef( source, AL_MAX_DISTANCE, max_dist );
     }
 }
+
+ALvoid *
+SGSoundSample::load_file(const char *path, const char *file)
+{
+    ALvoid* data = 0;
+
+    SGPath samplepath( path );
+    if ( strlen(file) ) {
+        samplepath.append( file );
+    }
+
+#if defined(ALUT_API_MAJOR_VERSION) && ALUT_API_MAJOR_VERSION >= 1
+    ALfloat freqf;
+    data = alutLoadMemoryFromFile(samplepath.c_str(), &format, &size, &freqf );
+    if (data == NULL) {
+        throw sg_exception("Failed to load wav file.");
+    }
+    freq = (ALsizei)freqf;
+#else
+# if defined (__APPLE__)
+    alutLoadWAVFile( (ALbyte *)samplepath.c_str(),
+                     &format, &data, &size, &freq );
+# else
+    alutLoadWAVFile( (ALbyte *)samplepath.c_str(),
+                     &format, &data, &size, &freq, &loop );
+# endif
+    if ( print_openal_error("constructor (alutLoadWAVFile)") ) {
+        throw sg_exception("Failed to load wav file.");
+    }
+#endif
+
+    return data;
+}
+

simgear/sound/sample_openal.hxx

@@ -84,7 +84,6 @@ private:
     // configuration values
     ALenum format;
     ALsizei size;
-    ALvoid* data;
     ALsizei freq;
 
     double pitch;
@@ -98,15 +97,20 @@ private:
 
 public:
 
+     /**
+      * Empty constructor, can be used to read data to the systems
+      * memory and not to the driver.
+      */
+    SGSoundSample();
+
     /**
      * Constructor
      * @param path Path name to sound
      * @param file File name of sound
-     * @param cleanup Request clean up the intermediate data (this
        should usually be true unless you want to manipulate the data
        later.)
      */
-    SGSoundSample( const char *path, const char *file, bool cleanup );
+    SGSoundSample( const char *path, const char *file );
 
     /**
      * Constructor.
@@ -180,13 +184,6 @@ public:
         return size;
     }
 
-    /**
-     * Return a pointer to the raw data
-     */
-    inline char *get_data() {
-        return (char *)data;
-    }
-
     /**
      * Set position of sound source (uses same coordinate system as opengl)
      */
@@ -224,6 +221,11 @@ public:
      * no longer audible.
      */
     void set_max_dist( ALfloat dist );
+
+    /**
+     * Load a sound file into a memory buffer only.
+     */
+    ALvoid* load_file(const char *path, const char *file);
 };
 
 

simgear/sound/xmlsound.cxx

@@ -275,8 +275,7 @@ SGXmlSound::init(SGPropertyNode *root, SGPropertyNode *node, SGSoundMgr *sndmgr,
        // "alSource".  The semantics of what is going on here seems
        // confused and needs to be thought through more carefully.
         _sample = new SGSoundSample( path.c_str(),
-                                    node->getStringValue("path", ""),
+                                    node->getStringValue("path", "") );
-                                    true );
 
        _mgr->add( _sample, _name );
    }