Make a separate demo for audio effect processors. Return information about the system audio in InitAudioDevice()

examples/audio/audio_effect_processor.c

@@ -0,0 +1,179 @@
+/*******************************************************************************************
+*
+*   raylib [audio] example - Audio effects (streaming)
+*
+*   This example has been created using raylib 1.3 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2015 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+#include <stdlib.h>
+
+#define AUDIO_THREAD_MUSIC_UPDATE true
+
+// a simple lowpass filter applied to the music stream
+static void processFilterEffect(float* buffer, unsigned int nframes)
+{
+    static float low[2] = { 0.0f, 0.0f };
+    static const float cutoff = 70.0f / 44100.0f; // 70 Hz lowpass filter
+    const float k = cutoff / (cutoff + 0.1591549431f); // RC filter formula
+
+    for (unsigned int i = 0; i < nframes*2; i+=2)
+    {
+        float l = buffer[i], r = buffer[i + 1];
+        low[0] += k * (l - low[0]);
+        low[1] += k * (r - low[1]);
+        buffer[i] = low[0];
+        buffer[i + 1] = low[1];
+    }
+}
+
+
+float* delayBuffer = NULL;
+unsigned int delayBufferSize = 0;
+unsigned int delayReadIndex = 2;
+unsigned int delayWriteIndex = 0;
+static void processDelayEffect(float* buffer, unsigned int nframes)
+{
+    for (unsigned int i = 0; i < nframes*2; i+=2)
+    {
+        float leftDelay = delayBuffer[delayReadIndex++];
+        float rightDelay = delayBuffer[delayReadIndex++];
+        if (delayReadIndex == delayBufferSize) delayReadIndex = 0;
+
+        buffer[i] = 0.5f * buffer[i] + 0.5f * leftDelay;
+        buffer[i+1] = 0.5f * buffer[i+1] + 0.5f * rightDelay;
+
+        delayBuffer[delayWriteIndex++] = buffer[i];
+        delayBuffer[delayWriteIndex++] = buffer[i+1];
+        if (delayWriteIndex == delayBufferSize) delayWriteIndex = 0;
+    }
+}
+
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib [audio] example - audio effects");
+
+    AudioDeviceInfo audioDevice = InitAudioDevice();              // Initialize audio device
+    if (!audioDevice.channels) return -1;
+    
+    // allocate buffer for the delay effect
+    delayBufferSize = audioDevice.channels * audioDevice.sampleRate; // 1s delay
+    delayBuffer = (float*)RL_CALLOC(delayBufferSize, sizeof(float));
+
+    Music music = LoadMusicStream("resources/country.mp3");
+    music.background = AUDIO_THREAD_MUSIC_UPDATE;
+
+    PlayMusicStream(music);
+
+    float timePlayed = 0.0f;
+    bool pause = false;
+    bool hasFilter = false;
+    bool hasDelay = false;
+
+    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        if (!AUDIO_THREAD_MUSIC_UPDATE)
+        {
+            UpdateMusicStream(music);   // Update music buffer with new stream data
+        }
+
+        // Restart music playing (stop and play)
+        if (IsKeyPressed(KEY_SPACE))
+        {
+            StopMusicStream(music);
+            PlayMusicStream(music);
+        }
+
+        // Pause/Resume music playing
+        if (IsKeyPressed(KEY_P))
+        {
+            pause = !pause;
+
+            if (pause) PauseMusicStream(music);
+            else ResumeMusicStream(music);
+        }
+
+        // Add/Remove effects
+        if (IsKeyPressed(KEY_F))
+        {
+            hasFilter = !hasFilter;
+            if (hasFilter)
+            {
+                AddAudioStreamProcessor(music.stream, &processFilterEffect);
+            }
+            else
+            {
+                RemoveAudioStreamProcessor(music.stream, &processFilterEffect);
+            }
+        }
+
+        if (IsKeyPressed(KEY_D))
+        {
+            hasDelay = !hasDelay;
+            if (hasDelay)
+            {
+                AddAudioStreamProcessor(music.stream, &processDelayEffect);
+            }
+            else
+            {
+                RemoveAudioStreamProcessor(music.stream, &processDelayEffect);
+            }
+        }
+
+        // Get timePlayed scaled to bar dimensions (400 pixels)
+        timePlayed = GetMusicTimePlayed(music)/GetMusicTimeLength(music)*400;
+
+        if (timePlayed > 400) StopMusicStream(music);
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+
+            DrawText("MUSIC SHOULD BE PLAYING!", 255, 150, 20, LIGHTGRAY);
+
+            DrawRectangle(200, 200, 400, 12, LIGHTGRAY);
+            DrawRectangle(200, 200, (int)timePlayed, 12, MAROON);
+            DrawRectangleLines(200, 200, 400, 12, GRAY);
+            DrawRectangleLines(200, 200, 400, 12, GRAY);
+
+            DrawText("PRESS SPACE TO RESTART MUSIC", 215, 250, 20, LIGHTGRAY);
+            DrawText("PRESS P TO PAUSE/RESUME MUSIC", 208, 280, 20, LIGHTGRAY);
+            DrawText("PRESS F TO ADD/REMOVE FILTER EFFECT", 180, 310, 20, LIGHTGRAY);
+            DrawText("PRESS D TO ADD/REMOVE DELAY EFFECT", 180, 340, 20, LIGHTGRAY);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+
+    UnloadMusicStream(music);   // Unload music stream buffers from RAM
+
+    CloseAudioDevice();         // Close audio device (music streaming is automatically stopped)
+
+    RL_FREE(delayBuffer);       // Free delay buffer
+
+    CloseWindow();              // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}

examples/audio/audio_music_stream.c

@@ -14,23 +14,6 @@
 
 #define AUDIO_THREAD_MUSIC_UPDATE true
 
-// a simple lowpass filter applied to the music stream
-static void audioEffectDemo(float* buffer, unsigned int nframes)
-{
-    static float low[2] = { 0.0f, 0.0f };
-    static const float cutoff = 70.0f / 44100.0f; // 70 Hz lowpass filter
-    const float k = cutoff / (cutoff + 0.1591549431f); // RC filter formula
-
-    for (unsigned int i = 0; i < nframes*2; i+=2)
-    {
-        float l = buffer[i], r = buffer[i + 1];
-        low[0] += k * (l - low[0]);
-        low[1] += k * (r - low[1]);
-        buffer[i] = low[0];
-        buffer[i + 1] = low[1];
-    }
-}
-
 int main(void)
 {
     // Initialization
@@ -49,7 +32,6 @@ int main(void)
 
     float timePlayed = 0.0f;
     bool pause = false;
-    bool hasfx = false;
 
     SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
     //--------------------------------------------------------------------------------------
@@ -80,20 +62,6 @@ int main(void)
             else ResumeMusicStream(music);
         }
 
-        // Add/Remove effect
-        if (IsKeyPressed(KEY_F))
-        {
-            hasfx = !hasfx;
-            if (hasfx)
-            {
-                AddAudioStreamProcessor(music.stream, &audioEffectDemo);
-            }
-            else
-            {
-                RemoveAudioStreamProcessor(music.stream, &audioEffectDemo);
-            }
-        }
-
         // Get timePlayed scaled to bar dimensions (400 pixels)
         timePlayed = GetMusicTimePlayed(music)/GetMusicTimeLength(music)*400;
 
@@ -111,11 +79,9 @@ int main(void)
             DrawRectangle(200, 200, 400, 12, LIGHTGRAY);
             DrawRectangle(200, 200, (int)timePlayed, 12, MAROON);
             DrawRectangleLines(200, 200, 400, 12, GRAY);
-            DrawRectangleLines(200, 200, 400, 12, GRAY);
 
             DrawText("PRESS SPACE TO RESTART MUSIC", 215, 250, 20, LIGHTGRAY);
             DrawText("PRESS P TO PAUSE/RESUME MUSIC", 208, 280, 20, LIGHTGRAY);
-            DrawText("PRESS F TO ADD/REMOVE EFFECT", 208, 310, 20, LIGHTGRAY);
 
         EndDrawing();
         //----------------------------------------------------------------------------------

src/raudio.c

@@ -418,8 +418,13 @@ void UntrackAudioBuffer(AudioBuffer *buffer);
 // Module Functions Definition - Audio Device initialization and Closing
 //----------------------------------------------------------------------------------
 // Initialize audio device
-void InitAudioDevice(void)
+AudioDeviceInfo InitAudioDevice(void)
 {
+    AudioDeviceInfo deviceInfo;
+    deviceInfo.sampleRate = 0;
+    deviceInfo.channels = 0;
+    deviceInfo.bufferSize = 0;
+
     // Init audio context
     ma_context_config ctxConfig = ma_context_config_init();
     ctxConfig.logCallback = OnLog;
@@ -428,7 +433,7 @@ void InitAudioDevice(void)
     if (result != MA_SUCCESS)
     {
         TRACELOG(LOG_WARNING, "AUDIO: Failed to initialize context");
-        return;
+        return deviceInfo;
     }
 
     // Init audio device
@@ -449,7 +454,7 @@ void InitAudioDevice(void)
     {
         TRACELOG(LOG_WARNING, "AUDIO: Failed to initialize playback device");
         ma_context_uninit(&AUDIO.System.context);
-        return;
+        return deviceInfo;
     }
 
     // Keep the device running the whole time. May want to consider doing something a bit smarter and only have the device running
@@ -460,7 +465,7 @@ void InitAudioDevice(void)
         TRACELOG(LOG_WARNING, "AUDIO: Failed to start playback device");
         ma_device_uninit(&AUDIO.System.device);
         ma_context_uninit(&AUDIO.System.context);
-        return;
+        return deviceInfo;
     }
 
     // Mixing happens on a seperate thread which means we need to synchronize. I'm using a mutex here to make things simple, but may
@@ -470,7 +475,7 @@ void InitAudioDevice(void)
         TRACELOG(LOG_WARNING, "AUDIO: Failed to create mutex for mixing");
         ma_device_uninit(&AUDIO.System.device);
         ma_context_uninit(&AUDIO.System.context);
-        return;
+        return deviceInfo;
     }
 
     // Init dummy audio buffers pool for multichannel sound playing
@@ -489,6 +494,11 @@ void InitAudioDevice(void)
     TRACELOG(LOG_INFO, "    > Periods size:  %d", AUDIO.System.device.playback.internalPeriodSizeInFrames*AUDIO.System.device.playback.internalPeriods);
 
     AUDIO.System.isReady = true;
+
+    deviceInfo.sampleRate = AUDIO.System.device.playback.internalSampleRate;
+    deviceInfo.channels = AUDIO.System.device.playback.channels;
+    deviceInfo.bufferSize = AUDIO.System.device.playback.internalPeriodSizeInFrames;
+    return deviceInfo;
 }
 
 // Close the audio device for all contexts
@@ -2195,6 +2205,7 @@ static ma_uint32 ReadAudioBufferFramesInInternalFormat(AudioBuffer *audioBuffer,
     if (audioBuffer->audioCallback)
     {
         audioBuffer->audioCallback(framesOut, frameCount, audioBuffer->audioCallbackData);
+        audioBuffer->framesProcessed += frameCount;
         return frameCount;
     }
 

src/raudio.h

@@ -114,6 +114,13 @@ typedef struct Music {
     void *ctxData;              // Audio context data, depends on type
 } Music;
 
+typedef struct AudioDeviceInfo
+{
+    unsigned int sampleRate;
+    unsigned int channels;
+    unsigned int bufferSize;
+} AudioDeviceInfo;
+
 //----------------------------------------------------------------------------------
 // Global Variables Definition
 //----------------------------------------------------------------------------------
@@ -128,7 +135,7 @@ extern "C" {            // Prevents name mangling of functions
 #endif
 
 // Audio device management functions
-void InitAudioDevice(void);                                     // Initialize audio device and context
+AudioDeviceInfo InitAudioDevice(void);                          // Initialize audio device and context
 void CloseAudioDevice(void);                                    // Close the audio device and context
 bool IsAudioDeviceReady(void);                                  // Check if audio device has been initialized successfully
 void SetMasterVolume(float volume);                             // Set master volume (listener)
@@ -193,6 +200,7 @@ void SetAudioStreamBufferSizeDefault(int size);                 // Default size
 void SetAudioStreamCallback(AudioStream stream, void callback(void*, unsigned int, void*), void* callbackData);  // Audio thread callback to request new data
 void AddAudioStreamProcessor(AudioStream stream, void (*process)(float*, unsigned int));
 void RemoveAudioStreamProcessor(AudioStream stream, void (*process)(float*, unsigned int));
+
 #ifdef __cplusplus
 }
 #endif

src/raylib.h

@@ -453,6 +453,13 @@ typedef struct Music {
     void *ctxData;              // Audio context data, depends on type
 } Music;
 
+typedef struct AudioDeviceInfo
+{
+    unsigned int sampleRate;
+    unsigned int channels;
+    unsigned int bufferSize;
+} AudioDeviceInfo;
+
 // VrDeviceInfo, Head-Mounted-Display device parameters
 typedef struct VrDeviceInfo {
     int hResolution;                // Horizontal resolution in pixels
@@ -1469,7 +1476,7 @@ RLAPI RayCollision GetRayCollisionQuad(Ray ray, Vector3 p1, Vector3 p2, Vector3
 //------------------------------------------------------------------------------------
 
 // Audio device management functions
-RLAPI void InitAudioDevice(void);                                     // Initialize audio device and context
+RLAPI AudioDeviceInfo InitAudioDevice(void);                          // Initialize audio device and context
 RLAPI void CloseAudioDevice(void);                                    // Close the audio device and context
 RLAPI bool IsAudioDeviceReady(void);                                  // Check if audio device has been initialized successfully
 RLAPI void SetMasterVolume(float volume);                             // Set master volume (listener)