Play a sound when you jump

1 files changed, 111 insertions, 0 deletions

@@ -0,0 +1,111 @@
+#include "muxer.h"
+#include <cstdlib>
+#include <sndfile.h>
+#include <portaudio.h>
+#include <list>
+
+#define SAMPLE_RATE (44100)
+
+class Sound {
+  public:
+    Sound(const char* filename);
+    ~Sound();
+    
+    float* ptr;
+    unsigned long pos;
+    unsigned long len;
+};
+
+struct Muxer {
+  std::list<Sound> playing;
+  PaStream* stream;
+};
+
+inline void dealWithPaError(PaError err)
+{
+  if (err != paNoError)
+  {
+    printf("PortAudio error: %s\n", Pa_GetErrorText(err));
+    exit(-1);
+  }
+}
+
+int paMuxerCallback(const void*, void* outputBuffer, unsigned long framesPerBuffer, const PaStreamCallbackTimeInfo*, PaStreamCallbackFlags, void* userData)
+{
+  Muxer* muxer = (Muxer*) userData;
+  float* out = (float*) outputBuffer;
+  
+  for (unsigned long i = 0; i<framesPerBuffer; i++)
+  {
+    unsigned long curAmount = 0;
+    *out = 0;
+    
+    for (auto& sound : muxer->playing)
+    {
+      if (sound.pos < sound.len)
+      {
+        *out *= curAmount++;
+        *out += sound.ptr[sound.pos++];
+        *out /= (float) curAmount;
+      }
+    }
+    
+    out++;
+  }
+  
+  return 0;
+}
+
+static Muxer* muxer;
+
+void initMuxer()
+{
+  muxer = new Muxer();
+  
+  dealWithPaError(Pa_Initialize());
+  dealWithPaError(Pa_OpenDefaultStream(&(muxer->stream), 0, 1, paFloat32, SAMPLE_RATE, paFramesPerBufferUnspecified, paMuxerCallback, muxer));
+  dealWithPaError(Pa_StartStream(muxer->stream));
+}
+
+void destroyMuxer()
+{
+  dealWithPaError(Pa_AbortStream(muxer->stream));
+  dealWithPaError(Pa_CloseStream(muxer->stream));
+  dealWithPaError(Pa_Terminate());
+  
+  delete muxer;
+  muxer = 0;
+}
+
+void playSound(const char* filename)
+{
+  // First, clear out any sounds that have finished playing
+  muxer->playing.remove_if([] (Sound& value) { return value.pos >= value.len; });
+  
+  // Then, add the new sound
+  muxer->playing.emplace_back(filename);
+}
+
+Sound::Sound(const char* filename)
+{
+  SF_INFO info;
+  SNDFILE* file = sf_open(filename, SFM_READ, &info);
+  if (file == nullptr)
+  {
+    printf("LibSndFile error: %s\n", sf_strerror(file));
+    exit(-1);
+  }
+  
+  ptr = (float*) malloc(info.frames * info.channels * sizeof(float));
+  len = info.frames * info.channels;
+  pos = 0;
+  
+  sf_readf_float(file, ptr, info.frames);
+  
+  sf_close(file);
+}
+
+Sound::~Sound()
+{
+  free(ptr);
+}