Merge pull request #171 from MihailRis/lua_audio

lua audio api

src/audio/AL/ALAudio.cpp

@@ -25,7 +25,10 @@ Speaker* ALSound::newInstance(int priority, int channel) const {
         return nullptr;
     }
     AL_CHECK(alSourcei(source, AL_BUFFER, buffer));
-    return new ALSpeaker(al, source, priority, channel);
+
+    auto speaker = new ALSpeaker(al, source, priority, channel);
+    speaker->duration = duration;
+    return speaker;
 }
 
 ALStream::ALStream(ALAudio* al, std::shared_ptr<PCMStream> source, bool keepSource)
@@ -77,12 +80,51 @@ void ALStream::bindSpeaker(speakerid_t speaker) {
         sp->stop();
     }
     this->speaker = speaker;
+    sp = audio::get_speaker(speaker);
+    if (sp) {
+        auto alspeaker = dynamic_cast<ALSpeaker*>(sp);
+        alspeaker->stream = this;
+        alspeaker->duration = source->getTotalDuration();
+    }
 }
 
 speakerid_t ALStream::getSpeaker() const {
     return speaker;
 }
 
+void ALStream::unqueueBuffers(uint alsource) {
+    uint processed = AL::getSourcei(alsource, AL_BUFFERS_PROCESSED);
+
+    while (processed--) {
+        uint buffer;
+        AL_CHECK(alSourceUnqueueBuffers(alsource, 1, &buffer));
+        unusedBuffers.push(buffer);
+
+        uint bps = source->getBitsPerSample()/8;
+        uint channels = source->getChannels();
+
+        ALint bufferSize;
+        alGetBufferi(buffer, AL_SIZE, &bufferSize);
+        totalPlayedSamples += bufferSize / bps / channels;
+        if (source->isSeekable()) {
+            totalPlayedSamples %= source->getTotalSamples();
+        }
+    }
+}
+
+uint ALStream::enqueueBuffers(uint alsource) {
+    uint preloaded = 0;
+    if (!unusedBuffers.empty()) {
+        uint buffer = unusedBuffers.front();
+        if (preloadBuffer(buffer, loop)) {
+            preloaded++;
+            unusedBuffers.pop();
+            AL_CHECK(alSourceQueueBuffers(alsource, 1, &buffer));
+        }
+    }
+    return preloaded;
+}
+
 void ALStream::update(double delta) {
     if (this->speaker == 0) {
         return;
@@ -93,24 +135,11 @@ void ALStream::update(double delta) {
         return;
     }
     ALSpeaker* alspeaker = dynamic_cast<ALSpeaker*>(speaker);
-    uint source = alspeaker->source;
-    uint processed = AL::getSourcei(source, AL_BUFFERS_PROCESSED);
-
-    while (processed--) {
-        uint buffer;
-        AL_CHECK(alSourceUnqueueBuffers(source, 1, &buffer));
-        unusedBuffers.push(buffer);
-    }
-
-    uint preloaded = 0;
-    if (!unusedBuffers.empty()) {
-        uint buffer = unusedBuffers.front();
-        if (preloadBuffer(buffer, loop)) {
-            preloaded++;
-            unusedBuffers.pop();
-            AL_CHECK(alSourceQueueBuffers(source, 1, &buffer));
-        }
-    }
+    uint alsource = alspeaker->source;
+    
+    unqueueBuffers(alsource);
+    uint preloaded = enqueueBuffers(alsource);
+    
     if (speaker->isStopped() && !alspeaker->stopped) {
         if (preloaded) {
             speaker->play();
@@ -120,8 +149,38 @@ void ALStream::update(double delta) {
     }
 }
 
+duration_t ALStream::getTime() const {
+    uint total = totalPlayedSamples;
+    auto alspeaker = dynamic_cast<ALSpeaker*>(audio::get_speaker(this->speaker));
+    if (alspeaker) {
+        uint alsource = alspeaker->source;
+        total += static_cast<duration_t>(AL::getSourcef(alsource, AL_SAMPLE_OFFSET));
+        if (source->isSeekable()) {
+            total %= source->getTotalSamples();
+        }
+    }
+    return total / static_cast<duration_t>(source->getSampleRate());
+}
+
 void ALStream::setTime(duration_t time) {
-    // TODO: implement
+    if (!source->isSeekable())
+        return;
+    uint sample = time * source->getSampleRate();
+    source->seek(sample);
+    auto alspeaker = dynamic_cast<ALSpeaker*>(audio::get_speaker(this->speaker));
+    if (alspeaker) {
+        bool paused = alspeaker->isPaused();
+        AL_CHECK(alSourceStop(alspeaker->source));
+        unqueueBuffers(alspeaker->source);
+        totalPlayedSamples = sample;
+        enqueueBuffers(alspeaker->source);
+        AL_CHECK(alSourcePlay(alspeaker->source));
+        if (paused) {
+            AL_CHECK(alSourcePause(alspeaker->source));
+        }
+    } else {
+        totalPlayedSamples = sample;
+    }
 }
 
 ALSpeaker::ALSpeaker(ALAudio* al, uint source, int priority, int channel) 
@@ -199,15 +258,32 @@ void ALSpeaker::stop() {
     stopped = true;
     if (source) {
         AL_CHECK(alSourceStop(source));
+
+        uint processed = AL::getSourcei(source, AL_BUFFERS_PROCESSED);
+        while (processed--) {
+            uint buffer;
+            AL_CHECK(alSourceUnqueueBuffers(source, 1, &buffer));
+            al->freeBuffer(buffer);
+        }
         al->freeSource(source);
     }
 }
 
 duration_t ALSpeaker::getTime() const {
+    if (stream) {
+        return stream->getTime();
+    }
     return static_cast<duration_t>(AL::getSourcef(source, AL_SEC_OFFSET));
 }
 
+duration_t ALSpeaker::getDuration() const {
+    return duration;
+}
+
 void ALSpeaker::setTime(duration_t time) {
+    if (stream) {
+        return stream->setTime(time);
+    }
     AL_CHECK(alSourcef(source, AL_SEC_OFFSET, static_cast<float>(time)));
 }
 

src/audio/AL/ALAudio.h

@@ -55,7 +55,11 @@ namespace audio {
         bool loop = false;
 
         bool preloadBuffer(uint buffer, bool loop);
+        void unqueueBuffers(uint alsource);
+        uint enqueueBuffers(uint alsource);
     public:
+        size_t totalPlayedSamples = 0;
+
         ALStream(ALAudio* al, std::shared_ptr<PCMStream> source, bool keepSource);
         ~ALStream();
 
@@ -64,6 +68,8 @@ namespace audio {
         Speaker* createSpeaker(bool loop, int channel) override;
         speakerid_t getSpeaker() const override;
         void update(double delta) override;
+        
+        duration_t getTime() const override;
         void setTime(duration_t time) override;       
 
         static inline constexpr uint STREAM_BUFFERS = 3; 
@@ -76,9 +82,11 @@ namespace audio {
         int channel;
         float volume = 0.0f;
     public:
+        ALStream* stream = nullptr;
         bool stopped = true;
         bool paused = false;
         uint source;
+        duration_t duration = 0.0f;
 
         ALSpeaker(ALAudio* al, uint source, int priority, int channel);
         ~ALSpeaker();
@@ -102,6 +110,7 @@ namespace audio {
         void stop() override;
 
         duration_t getTime() const override;
+        duration_t getDuration() const override;
         void setTime(duration_t time) override;
 
         void setPosition(glm::vec3 pos) override;

src/audio/NoAudio.h

@@ -53,6 +53,10 @@ namespace audio {
         void update(double delta) override {
         }
 
+        duration_t getTime() const override {
+            return 0.0;
+        }
+
         void setTime(duration_t time) override {
         }
     };

src/audio/audio.cpp

@@ -347,6 +347,14 @@ Channel* audio::get_channel(int index) {
     return channels.at(index).get();
 }
 
+std::shared_ptr<Stream> audio::get_associated_stream(speakerid_t id) {
+    auto found = streams.find(id);
+    if (found != streams.end()) {
+        return found->second;
+    }
+    return nullptr;
+}
+
 size_t audio::count_speakers() {
     return speakers.size();
 }

src/audio/audio.h

@@ -182,6 +182,9 @@ namespace audio {
         /// @param delta time elapsed since the last update
         virtual void update(double delta) = 0;
 
+        /// @brief Get current stream time
+        virtual duration_t getTime() const = 0;
+
         /// @brief Set playhead to the selected time
         /// @param time selected time
         virtual void setTime(duration_t time) = 0;
@@ -269,6 +272,9 @@ namespace audio {
         /// @return time position in seconds
         virtual duration_t getTime() const = 0;
 
+        /// @brief Get playing audio total duration
+        virtual duration_t getDuration() const = 0;
+
         /// @brief Set playing audio time position
         /// @param time time position in seconds
         virtual void setTime(duration_t time) = 0;
@@ -470,6 +476,11 @@ namespace audio {
     /// @return channel or nullptr
     extern Channel* get_channel(int index);
 
+    /// @brief Get stream associated with speaker
+    /// @param id speaker id
+    /// @return stream or nullptr
+    extern std::shared_ptr<Stream> get_associated_stream(speakerid_t id);
+
     /// @brief Get alive speakers number (including paused)
     extern size_t count_speakers();
 

src/coders/ogg.cpp

@@ -134,7 +134,7 @@ public:
 
     void seek(size_t position) override {
         if (!closed && seekable) {
-            ov_raw_seek(&vf, position);
+            ov_pcm_seek(&vf, position);
         }
     }
 };

src/engine.cpp

@@ -276,6 +276,10 @@ EnginePaths* Engine::getPaths() {
 	return paths;
 }
 
+ResPaths* Engine::getResPaths() {
+    return resPaths.get();
+}
+
 std::shared_ptr<Screen> Engine::getScreen() {
     return screen;
 }

src/engine.h

@@ -106,6 +106,9 @@ public:
     /** Get engine filesystem paths source */
 	EnginePaths* getPaths();
 
+    /** Get engine resource paths controller */ 
+    ResPaths* getResPaths();
+
     /** Get current Content instance */
 	const Content* getContent() const;
 

src/logic/scripting/lua/LuaState.cpp

@@ -122,6 +122,7 @@ void lua::LuaState::createLibs() {
     openlib("time", timelib, 0);
     openlib("file", filelib, 0);
     openlib("gui", guilib, 0);
+    openlib("audio", audiolib, 0);
 
     addfunc("print", lua_wrap_errors<l_print>);
 }

src/logic/scripting/lua/api_lua.h

@@ -15,6 +15,7 @@ extern const luaL_Reg playerlib [];
 extern const luaL_Reg inventorylib [];
 extern const luaL_Reg guilib [];
 extern const luaL_Reg hudlib [];
+extern const luaL_Reg audiolib [];
 
 
 // Lua Overrides

src/logic/scripting/lua/libaudio.cpp

@@ -0,0 +1,418 @@
+#include "api_lua.h"
+#include "lua_commons.h"
+#include "lua_util.h"
+
+#include "../../../audio/audio.h"
+#include "../../../engine.h"
+#include "../scripting.h"
+
+inline const char* DEFAULT_CHANNEL = "regular";
+
+inline int extract_channel_index(lua_State* L, int idx) {
+    const char* channel = DEFAULT_CHANNEL;
+    if (!lua_isnoneornil(L, idx)) {
+        channel = lua_tostring(L, idx);
+    }
+    return audio::get_channel_index(channel);
+}
+
+inline audio::speakerid_t play_sound(
+    const char* name,
+    bool relative,
+    lua::luanumber x,
+    lua::luanumber y,
+    lua::luanumber z,
+    lua::luanumber volume,
+    lua::luanumber pitch,
+    bool loop,
+    int channel
+) {
+    if (channel == -1)
+        return 0;
+    auto assets = scripting::engine->getAssets();
+    auto sound = assets->getSound(name);
+    if (sound == nullptr) {
+        return 0;
+    }
+
+    return audio::play(
+        sound, 
+        glm::vec3(
+            static_cast<float>(x), 
+            static_cast<float>(y), 
+            static_cast<float>(z)
+        ), 
+        false, 
+        volume, 
+        pitch, 
+        false, 
+        audio::PRIORITY_NORMAL, 
+        channel
+    );
+}
+
+inline audio::speakerid_t play_stream(
+    const char* filename,
+    bool relative,
+    lua::luanumber x,
+    lua::luanumber y,
+    lua::luanumber z,
+    lua::luanumber volume,
+    lua::luanumber pitch,
+    bool loop,
+    int channel
+) {
+    if (channel == -1)
+        return 0;
+    auto paths = scripting::engine->getResPaths();
+    fs::path file = paths->find(fs::path(filename));
+    return audio::play_stream(
+        file, 
+        glm::vec3(
+            static_cast<float>(x), 
+            static_cast<float>(y), 
+            static_cast<float>(z)
+        ), 
+        relative, 
+        volume, 
+        pitch, 
+        loop, 
+        channel
+    );
+}
+
+/// @brief audio.play_stream(
+///            name: string,
+///            x: number, 
+///            y: number, 
+///            z: number, 
+///            volume: number,
+///            pitch: number,
+///            channel: string = "regular",
+///            loop: bool = false)
+static int l_audio_play_stream(lua_State* L) {
+    lua_pushinteger(L, static_cast<lua::luaint>(
+        play_stream(
+            lua_tostring(L, 1),
+            false,
+            lua_tonumber(L, 2),
+            lua_tonumber(L, 3),
+            lua_tonumber(L, 4),
+            lua_tonumber(L, 5),
+            lua_tonumber(L, 6),
+            lua_toboolean(L, 8),
+            extract_channel_index(L, 7)
+        )
+    ));
+    return 1;
+}
+
+/// @brief audio.play_stream_2d(
+///            name: string,
+///            volume: number,
+///            pitch: number,
+///            channel: string = "regular",
+///            loop: bool = false)
+static int l_audio_play_stream_2d(lua_State* L) {
+    lua_pushinteger(L, static_cast<lua::luaint>(
+        play_stream(
+            lua_tostring(L, 1),
+            true,
+            0.0, 0.0, 0.0,
+            lua_tonumber(L, 2),
+            lua_tonumber(L, 3),
+            lua_toboolean(L, 5),
+            extract_channel_index(L, 4)
+        )
+    ));
+    return 1;
+}
+
+/// @brief audio.play_sound(
+///            name: string, 
+///            x: number, 
+///            y: number, 
+///            z: number, 
+///            volume: number,
+///            pitch: number,
+///            channel: string = "regular",
+///            loop: bool = false)
+static int l_audio_play_sound(lua_State* L) {
+    lua_pushinteger(L, static_cast<lua::luaint>(
+        play_sound(
+            lua_tostring(L, 1),
+            false,
+            lua_tonumber(L, 2),
+            lua_tonumber(L, 3),
+            lua_tonumber(L, 4),
+            lua_tonumber(L, 5),
+            lua_tonumber(L, 6),
+            lua_toboolean(L, 8),
+            extract_channel_index(L, 7)
+        )
+    ));
+    return 1;
+}
+
+/// @brief audio.play_sound_2d(
+///            name: string, 
+///            volume: number,
+///            pitch: number,
+///            channel: string = "regular",
+///            loop: bool = false)
+static int l_audio_play_sound_2d(lua_State* L) {
+    lua_pushinteger(L, static_cast<lua::luaint>(
+        play_sound(
+            lua_tostring(L, 1),
+            true,
+            0.0, 0.0, 0.0,
+            lua_tonumber(L, 2),
+            lua_tonumber(L, 3),
+            lua_toboolean(L, 5),
+            extract_channel_index(L, 4)
+        )
+    ));
+    return 1;
+}
+
+/// @brief audio.stop(speakerid: integer) -> nil
+static int l_audio_stop(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        speaker->stop();
+    }
+    return 0;
+}
+
+/// @brief audio.pause(speakerid: integer) -> nil 
+static int l_audio_pause(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        speaker->pause();
+    }
+    return 0;
+}
+
+/// @brief audio.resume(speakerid: integer) -> nil 
+static int l_audio_resume(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr && speaker->isPaused()) {
+        speaker->play();
+    }
+    return 0;
+}
+
+/// @brief audio.set_loop(speakerid: integer, value: bool) -> nil 
+static int l_audio_set_loop(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        bool value = lua_toboolean(L, 2);
+        speaker->setLoop(value);
+    }
+    return 0;
+}
+
+/// @brief audio.set_volume(speakerid: integer, value: number) -> nil 
+static int l_audio_set_volume(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua::luanumber value = lua_tonumber(L, 2);
+        speaker->setVolume(static_cast<float>(value));
+    }
+    return 0;
+}
+
+/// @brief audio.set_pitch(speakerid: integer, value: number) -> nil 
+static int l_audio_set_pitch(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua::luanumber value = lua_tonumber(L, 2);
+        speaker->setPitch(static_cast<float>(value));
+    }
+    return 0;
+}
+
+/// @brief audio.set_time(speakerid: integer, value: number) -> nil 
+static int l_audio_set_time(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua::luanumber value = lua_tonumber(L, 2);
+        speaker->setTime(static_cast<audio::duration_t>(value));
+    }
+    return 0;
+}
+
+/// @brief audio.set_position(speakerid: integer, x: number, y: number, z: number) -> nil
+static int l_audio_set_position(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua::luanumber x = lua_tonumber(L, 2);
+        lua::luanumber y = lua_tonumber(L, 3);
+        lua::luanumber z = lua_tonumber(L, 4);
+        speaker->setPosition(glm::vec3(
+            static_cast<float>(x),
+            static_cast<float>(y),
+            static_cast<float>(z)
+        ));
+    }
+    return 0;
+}
+
+/// @brief audio.set_velocity(speakerid: integer, x: number, y: number, z: number) -> nil
+static int l_audio_set_velocity(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua::luanumber x = lua_tonumber(L, 2);
+        lua::luanumber y = lua_tonumber(L, 3);
+        lua::luanumber z = lua_tonumber(L, 4);
+        speaker->setVelocity(glm::vec3(
+            static_cast<float>(x),
+            static_cast<float>(y),
+            static_cast<float>(z)
+        ));
+    }
+    return 0;
+}
+
+/// @brief audio.is_playing(speakerid: integer) -> bool 
+static int l_audio_is_playing(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua_pushboolean(L, speaker->isPlaying());
+        return 1;
+    }
+    lua_pushboolean(L, false);
+    return 1;
+}
+
+/// @brief audio.is_paused(speakerid: integer) -> bool 
+static int l_audio_is_paused(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua_pushboolean(L, speaker->isPaused());
+        return 1;
+    }
+    lua_pushboolean(L, false);
+    return 1;
+}
+
+/// @brief audio.is_loop(speakerid: integer) -> bool
+static int l_audio_is_loop(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua_pushboolean(L, speaker->isLoop());
+        return 1;
+    }
+    lua_pushboolean(L, false);
+    return 1;
+}
+
+/// @brief audio.get_volume(speakerid: integer) -> number
+static int l_audio_get_volume(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua_pushnumber(L, speaker->getVolume());
+        return 1;
+    }
+    lua_pushnumber(L, 0.0);
+    return 1;
+}
+
+/// @brief audio.get_pitch(speakerid: integer) -> number
+static int l_audio_get_pitch(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua_pushnumber(L, speaker->getPitch());
+        return 1;
+    }
+    lua_pushnumber(L, 1.0);
+    return 1;
+}
+
+/// @brief audio.get_time(speakerid: integer) -> number
+static int l_audio_get_time(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua_pushnumber(L, speaker->getTime());
+        return 1;
+    }
+    lua_pushnumber(L, 0.0);
+    return 1;
+}
+
+/// @brief audio.get_duration(speakerid: integer) -> number
+static int l_audio_get_duration(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        lua_pushnumber(L, speaker->getDuration());
+        return 1;
+    }
+    lua_pushnumber(L, 0.0);
+    return 1;
+}
+
+/// @brief audio.get_position(speakerid: integer) -> number, number, number
+static int l_audio_get_position(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        auto vec = speaker->getPosition();
+        lua::pushvec3(L, vec);
+        return 1;
+    }
+    return 0;
+}
+
+/// @brief audio.get_velocity(speakerid: integer) -> number, number, number
+static int l_audio_get_velocity(lua_State* L) {
+    lua::luaint id = lua_tonumber(L, 1);
+    auto speaker = audio::get_speaker(id);
+    if (speaker != nullptr) {
+        auto vec = speaker->getVelocity();
+        lua::pushvec3(L, vec);
+        return 1;
+    }
+    return 0;
+}
+
+const luaL_Reg audiolib [] = {
+    {"play_sound", lua_wrap_errors<l_audio_play_sound>},
+    {"play_sound_2d", lua_wrap_errors<l_audio_play_sound_2d>},
+    {"play_stream", lua_wrap_errors<l_audio_play_stream>},
+    {"play_stream_2d", lua_wrap_errors<l_audio_play_stream_2d>},
+    {"stop", lua_wrap_errors<l_audio_stop>},
+    {"pause", lua_wrap_errors<l_audio_pause>},
+    {"resume", lua_wrap_errors<l_audio_resume>},
+    {"set_loop", lua_wrap_errors<l_audio_set_loop>},
+    {"set_volume", lua_wrap_errors<l_audio_set_volume>},
+    {"set_pitch", lua_wrap_errors<l_audio_set_pitch>},
+    {"set_time", lua_wrap_errors<l_audio_set_time>},
+    {"set_position", lua_wrap_errors<l_audio_set_position>},
+    {"set_velocity", lua_wrap_errors<l_audio_set_velocity>},
+    {"is_playing", lua_wrap_errors<l_audio_is_playing>},
+    {"is_paused", lua_wrap_errors<l_audio_is_paused>},
+    {"is_loop", lua_wrap_errors<l_audio_is_loop>},
+    {"get_volume", lua_wrap_errors<l_audio_get_volume>},
+    {"get_pitch", lua_wrap_errors<l_audio_get_pitch>},
+    {"get_time", lua_wrap_errors<l_audio_get_time>},
+    {"get_duration", lua_wrap_errors<l_audio_get_duration>},
+    {"get_position", lua_wrap_errors<l_audio_get_position>},
+    {"get_velocity", lua_wrap_errors<l_audio_get_velocity>},
+    {NULL, NULL}
+};