Openal
- Thread starter Jan-Nik
- Start date
Pickle
Mega GP Mania
Jan-Nik said:
I think it might work, you will have to compile the lib yourself though. I thought I used for something but it appears maybe it was only for the pandora.
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Maybe check out this: OpenAL Soft !
Okay tried to play a sound and the good news is: It work's!
The bad news: performance. It wasn't possible to play 3 sounds at the same time without lag.
This is what I get when drawing a simple OpenGL Scene while playing a short sound:
0 sounds playing: 60 FPS
1 sound playing: 46 FPS
2 sounds playing: 36 FPS
3 sounds playing: 27 FPS (and sound stutter)
Listener and source where the same position and the sound was 2 seconds long, 44 kHz and mono.
The bad news: performance. It wasn't possible to play 3 sounds at the same time without lag.
This is what I get when drawing a simple OpenGL Scene while playing a short sound:
0 sounds playing: 60 FPS
1 sound playing: 46 FPS
2 sounds playing: 36 FPS
3 sounds playing: 27 FPS (and sound stutter)
Listener and source where the same position and the sound was 2 seconds long, 44 kHz and mono.
thanks for the info, not very promising, though. i might take a look at it, do you also have the the http://kcat.strangesoft.net/alure.html ported? or how/what file format did you load? wave? ogg? i'm just curious, because i dont really wanna use the blown sdl_mixer incl. sdl if there's a smaller lib can do that 
I've been using vorbisfile to load an ogg file. ALURE looks nice though, never heard of it before.crow_riot said:thanks for the info, not very promising, though. i might take a look at it, do you also have the the http://kcat.strangesoft.net/alure.html ported? or how/what file format did you load? wave? ogg? i'm just curious, because i dont really wanna use the blown sdl_mixer incl. sdl if there's a smaller lib can do that
Here's the part of my source code which handles sound:
Code:
#include <AL/al.h>
#include <AL/alc.h>
#include <vorbis/vorbisfile.h>
#include <stdexcept>
#include <boost/noncopyable.hpp>
class Sound : boost::noncopyable {
public:
Sound(ALuint buffer) : source_(0), buffer_(buffer)
{
alGenSources(1, &source_);
alListener3f(AL_POSITION, 0.0f, 0.0f, 0.0f);
alSource3f(source_, AL_POSITION, 0.0f, 0.0f, 0.0f);
alSourcei(source_, AL_BUFFER, buffer);
alSourcePlay(source_);
}
~Sound()
{
alSourceStop(source_);
alSourceUnqueueBuffers(source_, 1, &buffer_);
alDeleteSources(1, &source_);
}
bool IsPlaying()
{
ALint state;
alGetSourcei(source_, AL_SOURCE_STATE, &state);
return state == AL_PLAYING;
}
bool Stopped()
{
ALint state;
alGetSourcei(source_, AL_SOURCE_STATE, &state);
return state == AL_STOPPED;
}
void SetPitch(float p)
{
alSourcef(source_, AL_PITCH, p);
}
private:
ALuint source_;
ALuint buffer_;
};
class Audio : boost::noncopyable {
public:
Audio() : device_(0), context_(0)
{
device_ = alcOpenDevice(0);
if(!device_)
{
throw std::runtime_error("Could not open audio device.");
}
context_ = alcCreateContext(device_, 0);
if(context_)
{
alcMakeContextCurrent(context_);
}
else
{
throw std::runtime_error("Could not create audio context.");
}
}
~Audio()
{
alcMakeContextCurrent(0);
alcDestroyContext(context_);
alcCloseDevice(device_);
}
void Play(boost::shared_ptr<Sound> sound)
{
std::vector<boost::shared_ptr<Sound> >::iterator end = sounds_.end();
for(std::vector<boost::shared_ptr<Sound> >::iterator it = sounds_.begin(); it != end; ++it)
{
if((*it)->Stopped())
{
it = sounds_.erase(it);
}
}
sounds_.push_back(boost::shared_ptr<Sound>(sound));
}
void Stop(boost::shared_ptr<Sound> sound)
{
std::vector<boost::shared_ptr<Sound> >::iterator i;
if((i = std::find(sounds_.begin(), sounds_.end(), sound)) != sounds_.end()) // sound hasn't been loaded yet?
{
sounds_.erase(i);
}
}
private:
std::vector<boost::shared_ptr<Sound> > sounds_;
ALCdevice* device_;
ALCcontext* context_;
};
Audio& GetAudio()
{
static Audio audio_;
return audio_;
}
class SoundFile : boost::noncopyable {
public:
SoundFile(const std::string& filename) : sound_((Sound*)0)
{
Debug("Decoding "); Debug(filename); Debug(" ... ");
// based on http://www.gamedev.net/reference/articles/article2031.asp
FILE* f = fopen(filename.c_str(), "rb");
if(!f)
{
throw std::runtime_error("Could not open OGG file.");
}
OggVorbis_File oggFile;
if(ov_open(f, &oggFile, 0, 0) != 0)
{
throw std::runtime_error("Could not open OGG file.");
}
vorbis_info* pInfo;
pInfo = ov_info(&oggFile, -1);
ALenum format;
if(pInfo->channels == 1)
{
format = AL_FORMAT_MONO16;
}
else
{
format = AL_FORMAT_STEREO16;
}
ALsizei freq = pInfo->rate;
std::vector<char> bufferData;
const int bufferSize = 32768;
char array[bufferSize]; // 32 KB buffers
const int endian = 0; // 0 for Little-Endian, 1 for Big-Endian
int bitStream;
int bytes;
do
{
bytes = ov_read(&oggFile, array, bufferSize, endian, 2, 1, &bitStream);
if (bytes < 0)
{
ov_clear(&oggFile);
throw std::runtime_error("Error decoding OGG file.");
}
bufferData.insert(bufferData.end(), array, array + bytes);
}
while(bytes > 0);
ov_clear(&oggFile);
Debug("OK\n");
alGenBuffers(1, &buffer_);
alBufferData(buffer_, format, &bufferData[0], static_cast<ALsizei>(bufferData.size()), freq);
}
~SoundFile()
{
alDeleteBuffers(1, &buffer_);
}
void Play()
{
sound_.reset(new Sound(buffer_));
GetAudio().Play(sound_);
}
void Stop()
{
if(sound_)
{
GetAudio().Stop(sound_);
sound_.reset((Sound*)0);
}
}
bool IsPlaying()
{
if(sound_)
{
return sound_->IsPlaying();
}
return false;
}
void SetPitch(float p)
{
if(sound_)
{
sound_->SetPitch(p);
}
}
private:
boost::shared_ptr<Sound> sound_;
ALuint buffer_;
};
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thanks for sample. i tried SDL_mixer out now and i think i'll stick to that for the time being, though it has it's downsides
btw i've compiled the low-memory branch of tremor (an integer-only ogg decoder) for the wiz toolchain. works as a simple replacement for the current libvorbisidec in the toolchain.
source is here
http://svn.xiph.org/branches/lowmem-branch/Tremor/
the binary here
http://crow.riot.org/wiz/libvorbisidec.so.1.0.2.zip
if anyone wants to upload to the archive, feel free to do so
btw i've compiled the low-memory branch of tremor (an integer-only ogg decoder) for the wiz toolchain. works as a simple replacement for the current libvorbisidec in the toolchain.
source is here
http://svn.xiph.org/branches/lowmem-branch/Tremor/
the binary here
http://crow.riot.org/wiz/libvorbisidec.so.1.0.2.zip
if anyone wants to upload to the archive, feel free to do so
I've just found a mistake in my source, I was creating a new buffer for each source. I fixed it (and updated the source above), but it didn't improve performance
I also tried better RAM timings, but that didn't help either. What does help is overclocking.
I also tried better RAM timings, but that didn't help either. What does help is overclocking.
Yeah, SDL_mixer is definitely the better way on the Wiz, but unfortunately I need to change the pitch of sounds in my game which SDL_mixer doesn't support (or does it?).i tried SDL_mixer out now and i think i'll stick to that for the time being, though it has it's downsides
nope, sdl_mixer does not support pitching, but i've tried doing something similar. there's soundtouch, an opensource sound processing library @ http://www.surina.net/soundtouch/, which is capable of realtime speed/pitch shifting. in combination with sdl mixer's mix callback i think it could be done.Jan-Nik said:I've just found a mistake in my source, I was creating a new buffer for each source. I fixed it (and updated the source above), but it didn't improve performance
I also tried better RAM timings, but that didn't help either. What does help is overclocking.
Yeah, SDL_mixer is definitely the better way on the Wiz, but unfortunately I need to change the pitch of sounds in my game which SDL_mixer doesn't support (or does it?).i tried SDL_mixer out now and i think i'll stick to that for the time being, though it has it's downsides
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