add the option to tie a SampleGroup to the listener position and orientation

simgear/sound/sample_group.cxx

@@ -44,10 +44,9 @@ extern "C" int isinf (double);
 SGSampleGroup::SGSampleGroup () :
     _smgr(NULL),
     _active(false),
-    _changed(true),
-    _position_changed(true),
     _position(SGVec3d::zeros().data()),
-    _orientation(SGVec3f::zeros().data())
+    _orientation(SGVec3f::zeros().data()),
+    _tied_to_listener(false)
 {
     _samples.clear();
 }
@@ -55,10 +54,9 @@ SGSampleGroup::SGSampleGroup () :
 SGSampleGroup::SGSampleGroup ( SGSoundMgr *smgr, const string &refname ) :
     _smgr(smgr),
     _active(false), 
-    _changed(true),
-    _position_changed(true),
     _position(SGVec3d::zeros().data()),
-    _orientation(SGVec3f::zeros().data())
+    _orientation(SGVec3f::zeros().data()),
+    _tied_to_listener(false)
 {
     _smgr->add(this, refname);
     _active = _smgr->is_working();
@@ -134,6 +132,12 @@ void SGSampleGroup::update( double dt ) {
                 sample->set_buffer(buffer);
             }
 
+            if ( _tied_to_listener && _smgr->has_changed() ) {
+                sample->set_base_position( _smgr->get_position_vec() );
+                sample->set_orientation( _smgr->get_direction() );
+                sample->set_velocity( _smgr->get_velocity() );
+            }
+
             // start playing the sample
             ALuint buffer = sample->get_buffer();
             ALuint source = _smgr->request_source();
@@ -324,11 +328,13 @@ void SGSampleGroup::set_position( SGVec3d pos ) {
         return;
     }
 
-    sample_map_iterator sample_current = _samples.begin();
-    sample_map_iterator sample_end = _samples.end();
-    for ( ; sample_current != sample_end; ++sample_current ) {
-        SGSoundSample *sample = sample_current->second;
-        sample->set_base_position( pos );
+    if ( !_tied_to_listener ) {
+        sample_map_iterator sample_current = _samples.begin();
+        sample_map_iterator sample_end = _samples.end();
+        for ( ; sample_current != sample_end; ++sample_current ) {
+            SGSoundSample *sample = sample_current->second;
+            sample->set_base_position( pos );
+        }
     }
 }
 

simgear/sound/sample_group.hxx

@@ -156,18 +156,18 @@ public:
      */
     void load_file(SGSoundSample *sound);
 
+    inline void tie_to_listener() { _tied_to_listener = true; }
+
+
 protected:
     SGSoundMgr *_smgr;
     bool _active;
 
 private:
-    bool _changed;
-    bool _position_changed;
-
     float _volume;
-
     SGVec3d _position;
     SGVec3f _orientation;
+    bool _tied_to_listener;
 
     sample_map _samples;
 

simgear/sound/soundmgr_openal.cxx

@@ -204,7 +204,7 @@ void SGSoundMgr::update( double dt )
 // run the audio scheduler
 void SGSoundMgr::update_late( double dt ) {
     if (_working) {
-        // alcSuspendContext(_context);
+        alcSuspendContext(_context);
 
         sample_group_map_iterator sample_grp_current = _sample_groups.begin();
         sample_group_map_iterator sample_grp_end = _sample_groups.end();
@@ -222,7 +222,7 @@ void SGSoundMgr::update_late( double dt ) {
             testForALError("update");
             _changed = false;
         }
-        // alcProcessContext(_context);
+        alcProcessContext(_context);
     }
 }
 

simgear/sound/soundmgr_openal.hxx

@@ -18,8 +18,8 @@
 // General Public License for more details.
 //
 // You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+// along with this program; if not, write to the Free Software Foundation,
+// Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 //
 // $Id$
 
@@ -124,9 +124,8 @@ public:
         _changed = true;
     }
 
-    inline double *get_position() {
-       return _listener_pos.data();
-    }
+    inline double *get_position() { return _listener_pos.data(); }
+    inline SGVec3d get_position_vec() { return _listener_pos; };
 
     /**
      * set the velocity of the listener (in opengl coordinates)
@@ -136,11 +135,17 @@ public:
         _changed = true;
     }
 
+    inline SGVec3f get_velocity() { return _listener_vel; }
+
     /**
      * set the orientation of the listener (in opengl coordinates)
      */
     void set_orientation( SGQuatd ori );
 
+    inline SGVec3f get_direction() {
+        return SGVec3f(_listener_ori[0], _listener_ori[1], _listener_ori[2]);
+    }
+
     enum {
         NO_SOURCE = (unsigned int)-1,
         NO_BUFFER = (unsigned int)-1
@@ -160,10 +165,17 @@ public:
      */
     void release_source( unsigned int source );
 
+
+    /**
+     * returns true if the position has changed
+     */
+    inline bool has_changed() { return _changed; }
+
     static bool load(string &samplepath, void **data, int *format,
                                          unsigned int*size, int *freq );
 
 
+
 private:
     static int _alut_init;