build 200108. sound start offset support, default coupler sound naming cleanup, minor bug fixes

sound.h

@@ -102,6 +102,11 @@ public:
         name( std::string Name );
     std::string const &
         name() const;
+    // playback starting point shift setter/getter
+    void
+        start( float const Offset );
+    float const &
+        start() const;
     // returns true if there isn't any sound buffer associated with the object, false otherwise
     bool
         empty() const;
@@ -204,7 +209,8 @@ private:
     std::string m_name;
     int m_flags {}; // requested playback parameters
     sound_properties m_properties; // current properties of the emitted sounds
-    float m_pitchvariation {}; // emitter-specific shift in base pitch
+    float m_pitchvariation {}; // emitter-specific shift for base pitch
+    float m_startoffset {}; // emitter-specific shift for playback starting point
     bool m_stop { false }; // indicates active sample instances should be terminated
 /*
     bool m_stopend { false }; // indicates active instances of optional ending sound should be terminated
@@ -225,6 +231,9 @@ inline glm::vec3 const & sound_source::offset() const { return m_offset; }
 // sound source name setter/getter
 inline void sound_source::name( std::string Name ) { m_name = Name; }
 inline std::string const & sound_source::name() const { return m_name; }
+// playback starting point shift setter/getter
+inline void sound_source::start( float const Offset ) { m_startoffset = Offset; }
+inline float const & sound_source::start() const { return m_startoffset; }
 
 // collection of sound sources present in the scene
 class sound_table : public basic_table<sound_source> {