c++audiohardwaredriversopenal

OpenAL and Vista: Device is always 'Generic Software'


I'm writing the audio part of a game, and I'm using OpenAL. I want to use some extensions, but the tests always fail:

TRACE: AudioManager - Sound device: 'Generic Software'
TRACE: AudioManager - Enabling OpenAL extensions...
TRACE: AudioManager - Compressor support: NO
TRACE: AudioManager - Reverb support: YES
TRACE: AudioManager - Chorus support: NO
TRACE: AudioManager - Distortion support: NO
TRACE: AudioManager - Echo support: NO
TRACE: AudioManager - Flanger support: NO
TRACE: AudioManager - Frequency shifter support: NO
TRACE: AudioManager - Vocal morpher support: NO
TRACE: AudioManager - Pitch shifter support: NO
TRACE: AudioManager - Ring modulator support: NO
TRACE: AudioManager - AutoWAH support: NO
TRACE: AudioManager - Equalizer support: NO
TRACE: AudioManager - EAX Reverb support: YES

This is because I only get the Generic Software driver, which only supports reverb and EAX reverb. And not just on my machine, but others as well.

Here's how I detect the drivers for OpenAL to use:

ALchar device[256];
ZeroMemory(device, 256);
if (alcIsExtensionPresent(NULL, "ALC_ENUMERATE_ALL_EXT"))
{
    strcpy_s(device, 256, alcGetString(NULL, ALC_ALL_DEVICES_SPECIFIER));
}
else if (alcIsExtensionPresent(NULL, "ALC_ENUMERATION_EXT"))
{
    strcpy_s(device, 256, alcGetString(NULL, ALC_DEVICE_SPECIFIER));
}

TRACE_AUDIOMANAGER("Sound device: '%s'", device);

g_System = alcOpenDevice(device);

According to the specification, the device specifier should return two drivers: 'Generic Hardware' and 'Generic Software', separated by a NULL terminator.

My sound card is an "NVIDIA High Definition Audio" device which is using the nvhda32v.sys driver (version 1.0.0.63, updated on 11-11-2009).

Why doesn't OpenAL detect my hardware?


Solution

  • OpenAL should always return the default audio device, unless you are using a Creative audio card. The extensions are all Creative-specific. It's the same as expecting to get Intel-specific OpenGL extension on an NVIDIA videocard.

    For the record, here's how you set up OpenAL:

    // create a default device
    ALCdevice* device = alcOpenDevice("");
    if (!device)
    {
        LOG_ERROR("Could not create OpenAL device.");
        return false;
    }
    
    // context attributes, 2 zeros to terminate 
    ALint attribs[6] = {
        0, 0
    };
    
    ALCcontext* context = alcCreateContext(device, attribs);
    if (!context)
    {
        LOG_ERROR("Could not create OpenAL context.");
        alcCloseDevice(device);
        return false;
    }
    
    if (!alcMakeContextCurrent(context))
    {
        LOG_ERROR("Could not enable OpenAL context.");
        alcDestroyContext(context);
        alcCloseDevice(device);
        return false;
    }
    
    LOG_INFO("[OpenAL] Version: %s", alGetString(AL_VERSION));
    LOG_INFO("[OpenAL] Vendor: %s", alGetString(AL_VENDOR));
    LOG_INFO("[OpenAL] Renderer: %s", alGetString(AL_RENDERER));