chore: clean recommit

Examples/Audio/StreamEffects.cs

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+/*******************************************************************************************
+*
+*   raylib [audio] example - stream effects
+*
+*   Example complexity rating: [★★★★] 4/4
+*
+*   Example originally created with raylib 4.2, last time updated with raylib 5.0
+*
+*   Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
+*   BSD-like license that allows static linking with closed source software
+*
+*   Copyright (c) 2022-2025 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using static Raylib_cs.Raylib;
+
+namespace Examples.Audio;
+
+[ExcludeFromBrowser("AttachAudioStreamProcessor is unreliable on the wasm audio backend")]
+public unsafe partial class StreamEffects : IExample
+{
+    private const int screenWidth = 800;
+    private const int screenHeight = 450;
+
+    public string Name => "Audio / Stream Effects";
+
+    public string Title => "raylib [audio] example - stream effects";
+
+    //----------------------------------------------------------------------------------
+    // Global Variables Definition
+    //----------------------------------------------------------------------------------
+    private static float[] delayBuffer = null;
+    private static uint delayBufferSize = 0;
+    private static uint delayReadIndex = 2;
+    private static uint delayWriteIndex = 0;
+
+    // Low-pass filter state (was a function-local static in the C example)
+    private static readonly float[] low = { 0.0f, 0.0f };
+
+    private Music music;
+    private float timePlayed;
+    private bool pause;
+    private bool enableEffectLPF;
+    private bool enableEffectDelay;
+
+    public void Init()
+    {
+        InitAudioDevice();              // Initialize audio device
+
+        music = LoadMusicStream("resources/audio/country.mp3");
+
+        // Allocate buffer for the delay effect
+        delayBufferSize = 48000 * 2;    // 1 second delay (device sampleRate*channels)
+        delayBuffer = new float[delayBufferSize];
+        delayReadIndex = 2;
+        delayWriteIndex = 0;
+        low[0] = 0.0f;
+        low[1] = 0.0f;
+
+        PlayMusicStream(music);
+
+        timePlayed = 0.0f;              // Time played normalized [0.0f..1.0f]
+        pause = false;                  // Music playing paused
+
+        enableEffectLPF = false;        // Enable effect low-pass-filter
+        enableEffectDelay = false;      // Enable effect delay (1 second)
+    }
+
+    public void Update()
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        UpdateMusicStream(music);   // Update music buffer with new stream data
+
+        // Restart music playing (stop and play)
+        if (IsKeyPressed(KeyboardKey.Space))
+        {
+            StopMusicStream(music);
+            PlayMusicStream(music);
+        }
+
+        // Pause/Resume music playing
+        if (IsKeyPressed(KeyboardKey.P))
+        {
+            pause = !pause;
+
+            if (pause) PauseMusicStream(music);
+            else ResumeMusicStream(music);
+        }
+
+        // Add/Remove effect: lowpass filter
+        if (IsKeyPressed(KeyboardKey.F))
+        {
+            enableEffectLPF = !enableEffectLPF;
+            if (enableEffectLPF) AttachAudioStreamProcessor(music.Stream, &AudioProcessEffectLPF);
+            else DetachAudioStreamProcessor(music.Stream, &AudioProcessEffectLPF);
+        }
+
+        // Add/Remove effect: delay
+        if (IsKeyPressed(KeyboardKey.D))
+        {
+            enableEffectDelay = !enableEffectDelay;
+            if (enableEffectDelay) AttachAudioStreamProcessor(music.Stream, &AudioProcessEffectDelay);
+            else DetachAudioStreamProcessor(music.Stream, &AudioProcessEffectDelay);
+        }
+
+        // Get normalized time played for current music stream
+        timePlayed = GetMusicTimePlayed(music) / GetMusicTimeLength(music);
+
+        if (timePlayed > 1.0f) timePlayed = 1.0f;   // Make sure time played is no longer than music
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+        ClearBackground(Color.RayWhite);
+
+        DrawText("MUSIC SHOULD BE PLAYING!", 245, 150, 20, Color.LightGray);
+
+        DrawRectangle(200, 180, 400, 12, Color.LightGray);
+        DrawRectangle(200, 180, (int)(timePlayed * 400.0f), 12, Color.Maroon);
+        DrawRectangleLines(200, 180, 400, 12, Color.Gray);
+
+        DrawText("PRESS SPACE TO RESTART MUSIC", 215, 230, 20, Color.LightGray);
+        DrawText("PRESS P TO PAUSE/RESUME MUSIC", 208, 260, 20, Color.LightGray);
+
+        DrawText($"PRESS F TO TOGGLE LPF EFFECT: {(enableEffectLPF ? "ON" : "OFF")}", 200, 320, 20, Color.Gray);
+        DrawText($"PRESS D TO TOGGLE DELAY EFFECT: {(enableEffectDelay ? "ON" : "OFF")}", 180, 350, 20, Color.Gray);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    public void Unload()
+    {
+        UnloadMusicStream(music);   // Unload music stream buffers from RAM
+
+        CloseAudioDevice();         // Close audio device (music streaming is automatically stopped)
+
+        delayBuffer = null;         // Free delay buffer
+    }
+
+    //------------------------------------------------------------------------------------
+    // Module Functions Definition
+    //------------------------------------------------------------------------------------
+    // Audio effect: lowpass filter
+    [UnmanagedCallersOnly(CallConvs = new[] { typeof(CallConvCdecl) })]
+    private static void AudioProcessEffectLPF(void* buffer, uint frames)
+    {
+        const float cutoff = 70.0f / 44100.0f; // 70 Hz lowpass filter
+        const float k = cutoff / (cutoff + 0.1591549431f); // RC filter formula
+
+        // Converts the buffer data before using it
+        float* bufferData = (float*)buffer;
+        for (uint i = 0; i < frames * 2; i += 2)
+        {
+            float l = bufferData[i];
+            float r = bufferData[i + 1];
+
+            low[0] += k * (l - low[0]);
+            low[1] += k * (r - low[1]);
+            bufferData[i] = low[0];
+            bufferData[i + 1] = low[1];
+        }
+    }
+
+    // Audio effect: delay
+    [UnmanagedCallersOnly(CallConvs = new[] { typeof(CallConvCdecl) })]
+    private static void AudioProcessEffectDelay(void* buffer, uint frames)
+    {
+        float* bufferData = (float*)buffer;
+        fixed (float* delay = delayBuffer)
+        {
+            for (uint i = 0; i < frames * 2; i += 2)
+            {
+                float leftDelay = delay[delayReadIndex++];    // ERROR: Reading buffer -> WHY??? Maybe thread related???
+                float rightDelay = delay[delayReadIndex++];
+
+                if (delayReadIndex == delayBufferSize) delayReadIndex = 0;
+
+                bufferData[i] = 0.5f * bufferData[i] + 0.5f * leftDelay;
+                bufferData[i + 1] = 0.5f * bufferData[i + 1] + 0.5f * rightDelay;
+
+                delay[delayWriteIndex++] = bufferData[i];
+                delay[delayWriteIndex++] = bufferData[i + 1];
+                if (delayWriteIndex == delayBufferSize) delayWriteIndex = 0;
+            }
+        }
+    }
+
+    public static int Main()
+    {
+        // Initialization
+        //--------------------------------------------------------------------------------------
+        InitWindow(screenWidth, screenHeight, "raylib [audio] example - stream effects");
+
+        SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
+        //--------------------------------------------------------------------------------------
+
+        var game = new StreamEffects();
+        game.Init();
+
+        // Main game loop
+        while (!WindowShouldClose())    // Detect window close button or ESC key
+        {
+            game.Update();
+        }
+
+        game.Unload();
+
+        // De-Initialization
+        //--------------------------------------------------------------------------------------
+        CloseWindow();              // Close window and OpenGL context
+        //--------------------------------------------------------------------------------------
+
+        return 0;
+    }
+}