[AUDIO] Add a function to make an alias of a sound and share it's sam…

…ple data (#3219)

* Add a function to clone a sound and share data with another sound.

* rename items based on feedback

* PR Feedback, use custom unload for sound alias, not variant of normal sound unloading

src/raudio.c

@@ -916,6 +916,32 @@ Sound LoadSoundFromWave(Wave wave)
     return sound;
 }
 
+// Clone sound from existing sound data, clone does not own wave data
+// Wave data must 
+// NOTE: Wave data must be unallocated manually and will be shared across all clones
+Sound LoadSoundAlias(Sound source)
+{
+    Sound sound = { 0 };
+
+    if (source.stream.buffer->data != NULL)
+    {
+        AudioBuffer* audioBuffer = LoadAudioBuffer(AUDIO_DEVICE_FORMAT, AUDIO_DEVICE_CHANNELS, AUDIO.System.device.sampleRate, source.frameCount, AUDIO_BUFFER_USAGE_STATIC);
+        if (audioBuffer == NULL)
+        {
+            TRACELOG(LOG_WARNING, "SOUND: Failed to create buffer");
+            return sound; // early return to avoid dereferencing the audioBuffer null pointer
+        }
+        audioBuffer->data = source.stream.buffer->data;
+        sound.frameCount = source.frameCount;
+        sound.stream.sampleRate = AUDIO.System.device.sampleRate;
+        sound.stream.sampleSize = 32;
+        sound.stream.channels = AUDIO_DEVICE_CHANNELS;
+        sound.stream.buffer = audioBuffer;
+    }
+
+    return sound;
+}
+
 // Checks if a sound is ready
 bool IsSoundReady(Sound sound)
 {
@@ -940,6 +966,17 @@ void UnloadSound(Sound sound)
     //TRACELOG(LOG_INFO, "SOUND: Unloaded sound data from RAM");
 }
 
+void UnloadSoundAlias(Sound alias)
+{
+    // untrack and unload just the sound buffer, not the sample data, it is shared with the source for the alias
+    if (alias.stream.buffer != NULL)
+    {
+        ma_data_converter_uninit(&alias.stream.buffer->converter, NULL);
+        UntrackAudioBuffer(alias.stream.buffer);
+        RL_FREE(alias.stream.buffer);
+    }
+}
+
 // Update sound buffer with new data
 void UpdateSound(Sound sound, const void *data, int sampleCount)
 {

src/raylib.h

@@ -1533,10 +1533,12 @@ RLAPI Wave LoadWaveFromMemory(const char *fileType, const unsigned char *fileDat
 RLAPI bool IsWaveReady(Wave wave);                                    // Checks if wave data is ready
 RLAPI Sound LoadSound(const char *fileName);                          // Load sound from file
 RLAPI Sound LoadSoundFromWave(Wave wave);                             // Load sound from wave data
+RLAPI Sound LoadSoundAlias(Sound source);                            // Create a new sound that shares the same sample data as the source sound, does not own the sound data
 RLAPI bool IsSoundReady(Sound sound);                                 // Checks if a sound is ready
 RLAPI void UpdateSound(Sound sound, const void *data, int sampleCount); // Update sound buffer with new data
 RLAPI void UnloadWave(Wave wave);                                     // Unload wave data
 RLAPI void UnloadSound(Sound sound);                                  // Unload sound
+RLAPI void UnloadSoundAlias(Sound alias);                             // Unload a sound alias (does not deallocate sample data)
 RLAPI bool ExportWave(Wave wave, const char *fileName);               // Export wave data to file, returns true on success
 RLAPI bool ExportWaveAsCode(Wave wave, const char *fileName);         // Export wave sample data to code (.h), returns true on success