add `audio_sound_positionning` example

examples/audio/audio_sound_positioning.c

@@ -0,0 +1,115 @@
+/*******************************************************************************************
+*
+*   raylib [audio] example - Playing spatialized 3D sound
+*
+*   Example complexity rating: [★★☆☆] 2/4
+*
+*   Example originally created with raylib 5.5, last time updated with raylib 5.5
+*
+*   Example contributed by Le Juez Victor (@Bigfoot71) and reviewed by Ramon Santamaria (@raysan5)
+*
+*   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) 2025 Le Juez Victor (@Bigfoot71)
+*
+********************************************************************************************/
+
+#include <raylib.h>
+#include <raymath.h>
+
+//------------------------------------------------------------------------------------
+// Sound positioning function
+//------------------------------------------------------------------------------------
+static void SetSoundPosition(Camera listener, Sound sound, Vector3 position, float maxDist)
+{
+    // Calculate direction vector and distance between listener and sound source
+    Vector3 direction = Vector3Subtract(position, listener.position);
+    float distance = Vector3Length(direction);
+    
+    // Apply logarithmic distance attenuation and clamp between 0-1
+    float attenuation = 1.0f / (1.0f + (distance / maxDist));
+    attenuation = Clamp(attenuation, 0.0f, 1.0f);
+    
+    // Calculate normalized vectors for spatial positioning
+    Vector3 normalizedDirection = Vector3Normalize(direction);
+    Vector3 forward = Vector3Normalize(Vector3Subtract(listener.target, listener.position));
+    Vector3 right = Vector3Normalize(Vector3CrossProduct(forward, listener.up));
+    
+    // Reduce volume for sounds behind the listener
+    float dotProduct = Vector3DotProduct(forward, normalizedDirection);
+    if (dotProduct < 0.0f) {
+        attenuation *= (1.0f + dotProduct * 0.5f);
+    }
+    
+    // Set stereo panning based on sound position relative to listener
+    float pan = 0.5f + 0.5f * Vector3DotProduct(normalizedDirection, right);
+    
+    // Apply final sound properties
+    SetSoundVolume(sound, attenuation);
+    SetSoundPan(sound, pan);
+}
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    InitWindow(800, 600, "Quick Spatial Sound");
+    InitAudioDevice();
+
+    SetTargetFPS(60);
+    DisableCursor();
+
+    Sound sound = LoadSound("resources/coin.wav");
+
+    Camera camera = {
+        .position = (Vector3) { 0, 5, 5 },
+        .target = (Vector3) { 0, 0, 0 },
+        .up = (Vector3) { 0, 1, 0 },
+        .fovy = 60,
+    };
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        UpdateCamera(&camera, CAMERA_FREE);
+
+        float th = GetTime();
+
+        Vector3 spherePos = {
+            .x = 5.0f * cosf(th),
+            .y = 0.0f,
+            .z = 5.0f * sinf(th)
+        };
+
+        SetSoundPosition(camera, sound, spherePos, 20.0f);
+        if (!IsSoundPlaying(sound)) PlaySound(sound);
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+        {
+            ClearBackground(BLACK);
+
+            BeginMode3D(camera);
+                DrawGrid(10, 2);
+                DrawSphere(spherePos, 0.5f, RED);
+            EndMode3D();
+        }
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    UnloadSound(sound);
+    CloseAudioDevice();
+    CloseWindow();
+}