source: code/branches/tutorial/src/audio/AudioStream.cc @ 1992

/*
 *   ORXONOX - the hottest 3D action shooter ever to exist
 *
 *
 *   License notice:
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation; either version 2
 *   of the License, or (at your option) any later version.
 *
 *   This program 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 General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 *   Author:
 *      ...
 *   Co-authors:
 *      ...
 *
 */

#include <string>

#include "AudioStream.h"
#include "../orxonox/core/Debug.h"

namespace audio
{
  AudioStream::AudioStream(std::string path)
        {
                this->path = path;
                loaded = false;
        }

        void AudioStream::open()
        {
            int result;


            if(!(oggFile = fopen(path.c_str(), "rb")))
                        {
                orxonox::Error("Could not open Ogg file "+path);
                                return;
                        }

            if((result = ov_open(oggFile, &oggStream, NULL, 0)) < 0)
            {
        fclose(oggFile);
              orxonox::Error("Could not open Ogg stream. " + errorString(result));
                                return;
            }

                        loaded = true;

            vorbisInfo = ov_info(&oggStream, -1);
            vorbisComment = ov_comment(&oggStream, -1);

            if(vorbisInfo->channels == 1)
                format = AL_FORMAT_MONO16;
            else
                format = AL_FORMAT_STEREO16;


            alGenBuffers(2, buffers);
            check();
            alGenSources(1, &source);
            check();

            alSource3f(source, AL_POSITION,        0.0, 0.0, 0.0);
            alSource3f(source, AL_VELOCITY,        0.0, 0.0, 0.0);
            alSource3f(source, AL_DIRECTION,       0.0, 0.0, 0.0);
            alSourcef (source, AL_ROLLOFF_FACTOR,  0.0          );
            alSourcei (source, AL_SOURCE_RELATIVE, AL_FALSE      );
        }




        void AudioStream::release()
        {

            alSourceStop(source);
            empty();
            alDeleteSources(1, &source);
            check();
            alDeleteBuffers(1, buffers);
            check();

            ov_clear(&oggStream);
                        loaded = false;

        }




        void AudioStream::display()
        {
                if (loaded)
                {
            COUT(3)
                << "version         " << vorbisInfo->version         << std::endl
                << "channels        " << vorbisInfo->channels        << std::endl
                << "rate (hz)       " << vorbisInfo->rate            << std::endl
                << "bitrate upper   " << vorbisInfo->bitrate_upper   << std::endl
                << "bitrate nominal " << vorbisInfo->bitrate_nominal << std::endl
                << "bitrate lower   " << vorbisInfo->bitrate_lower   << std::endl
                << "bitrate window  " << vorbisInfo->bitrate_window  << std::endl
                << std::endl
                << "vendor " << vorbisComment->vendor << std::endl;

            for(int i = 0; i < vorbisComment->comments; i++)
                COUT(3) << "   " << vorbisComment->user_comments[i] << std::endl;

            COUT(3) << std::endl;
                }
        }




        bool AudioStream::playback()
        {
                if (!loaded)
                {
                        return false;
                }

            if(playing())
                return true;

            if(!stream(buffers[0]))
                return false;

            if(!stream(buffers[1]))
                return false;

            alSourceQueueBuffers(source, 2, buffers);
            alSourcePlay(source);

            return true;
        }




        bool AudioStream::playing()
        {
                if (!loaded)
                {
                        return false;
                }

            ALenum state;
            alGetSourcei(source, AL_SOURCE_STATE, &state);
            return (state == AL_PLAYING);
        }




        bool AudioStream::update()
        {
            int processed;
            bool active = true;

            alGetSourcei(source, AL_BUFFERS_PROCESSED, &processed);

            while(processed--)
            {
                ALuint buffer;

                alSourceUnqueueBuffers(source, 1, &buffer);
                check();

                active = stream(buffer);

                alSourceQueueBuffers(source, 1, &buffer);
                check();
            }

                        if (active==false)
                        {
                                loaded = false;
                        }
            return active;
        }




        bool AudioStream::stream(ALuint buffer)
        {
            char pcm[BUFFER_SIZE];
            int  size = 0;
            int  section;
            int  result;

            while(size < BUFFER_SIZE)
            {
                result = ov_read(&oggStream, pcm + size, BUFFER_SIZE - size, 0, 2, 1, &section);

                if(result > 0)
                    size += result;
                else
                    if(result < 0)
                        orxonox::Error(errorString(result));
                    else
                        break;
            }

            if(size == 0)
                return false;

            alBufferData(buffer, format, pcm, size, vorbisInfo->rate);
            check();

            return true;
        }



        void AudioStream::empty()
        {
            int queued;

            alGetSourcei(source, AL_BUFFERS_QUEUED, &queued);

            while(queued--)
            {
                ALuint buffer;

                alSourceUnqueueBuffers(source, 1, &buffer);
                check();
            }
        }




        void AudioStream::check()
        {
                int error = alGetError();

                if(error != AL_NO_ERROR)
                        orxonox::Error("OpenAL error was raised.");
        }



        std::string AudioStream::errorString(int code)
        {
            switch(code)
            {
                case OV_EREAD:
                    return std::string("Read from media.");
                case OV_ENOTVORBIS:
                    return std::string("Not Vorbis data.");
                case OV_EVERSION:
                    return std::string("Vorbis version mismatch.");
                case OV_EBADHEADER:
                    return std::string("Invalid Vorbis header.");
                case OV_EFAULT:
                    return std::string("Internal logic fault (bug or heap/stack corruption.");
                default:
                    return std::string("Unknown Ogg error.");
            }
        }
}