audio.cpp

/*
    Audio management.
    Copyright (C) 2015 Denis BOURGE

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
    USA
*/

#include "hx3d/audio/audio.hpp"
#include "hx3d/audio/effect.hpp"

#include "hx3d/utils/log.hpp"

#include <SDL2/SDL_mixer.h>

namespace hx3d {
namespace audio {

int AudioDevice::PostChannel = MIX_CHANNEL_POST;

AudioDevice::AudioDevice() {

  Log.Info("Audio device initialization.");

  int flags = Mix_Init(~0);
  std::string types;

  if (flags & MIX_INIT_FLAC)
    types += "\t- FLAC\n";
  if (flags & MIX_INIT_MOD)
    types += "\t- MOD\n";
  if (flags & MIX_INIT_MP3)
    types += "\t- MP3\n";
  if (flags & MIX_INIT_OGG)
    types += "\t- OGG\n";
  if (!flags)
    types += "\t- None\n";

  Log.Info("Supported audio types: \n%s", types.c_str());

  _bufferSize = 4096;

  Mix_OpenAudio(44100, AUDIO_S16SYS, 1, _bufferSize);
  Mix_QuerySpec(&_audioRate, &_audioFormat, &_audioChannels);

  _bits = _audioFormat & 0xFF;
  _sampleSize = (_bits / 8.f) + _audioChannels;

  Log.Info(
    "Audio device information: \n\
    \t - %d Hz / %d bits / %s / %d bytes buffer. \n\
    \t - Sample size: %d\n",
  _audioRate, _bits, _audioChannels > 1 ? "Stereo" : "Mono", _bufferSize,
  _sampleSize);
}

AudioDevice::~AudioDevice() {
  Mix_Quit();
}

void AudioDevice::registerEffect(const int channel, Effect& effect) {
  Mix_RegisterEffect(
    channel,
    [](int channel, void* stream, int len, void* udata){
      Effect* effect = (Effect*)udata;
      effect->onFunction(channel, stream, len);
    },
    [](int channel, void* udata){
      Effect* effect = (Effect*)udata;
      effect->onDone(channel);
    }, &effect);
}

void AudioDevice::clearEffects(const int channel) {
  Mix_UnregisterAllEffects(channel);
}

unsigned int AudioDevice::getFrequencyRate() {
  return _audioRate;
}

unsigned int AudioDevice::getSampleSize() {
  return _sampleSize;
}

} /* audio */
} /* hx3d */