examples/alure-dumb.cpp

   1 /*
   2  * An example showing how to use an external decoder to play files through the
   3  * DUMB library.
   4  */
   5
   6 #include <iostream>
   7 #include <iomanip>
   8 #include <cstring>
   9 #include <limits>
  10 #include <thread>
  11 #include <chrono>
  12
  13 #include "dumb.h"
  14
  15 #include "alure2.h"
  16
  17 namespace
  18 {
  19
  20 // Some I/O function callback wrappers for DUMB to read from an std::istream
  21 static int cb_skip(void *user_data, long offset)
  22 {
  23     std::istream *stream = static_cast<std::istream*>(user_data);
  24     stream->clear();
  25
  26     if(stream->seekg(offset, std::ios_base::cur))
  27         return 0;
  28     return 1;
  29 }
  30
  31 static long cb_read(char *ptr, long size, void *user_data)
  32 {
  33     std::istream *stream = static_cast<std::istream*>(user_data);
  34     stream->clear();
  35
  36     stream->read(ptr, size);
  37     return stream->gcount();
  38 }
  39
  40 static int cb_read_char(void *user_data)
  41 {
  42     std::istream *stream = static_cast<std::istream*>(user_data);
  43     stream->clear();
  44
  45     unsigned char ret;
  46     stream->read(reinterpret_cast<char*>(&ret), 1);
  47     if(stream->gcount() > 0) return ret;
  48     return -1;
  49 }
  50
  51 static int cb_seek(void *user_data, long n)
  52 {
  53     std::istream *stream = static_cast<std::istream*>(user_data);
  54     stream->clear();
  55
  56     if(!stream->seekg(n))
  57         return 1;
  58     return 0;
  59 }
  60
  61 static long cb_get_size(void *user_data)
  62 {
  63     std::istream *stream = static_cast<std::istream*>(user_data);
  64     stream->clear();
  65
  66     long len = -1;
  67     std::streampos pos = stream->tellg();
  68     if(pos != -1 && stream->seekg(0, std::ios::end))
  69     {
  70         len = stream->tellg();
  71         stream->seekg(pos);
  72     }
  73     return len;
  74 }
  75
  76
  77 // Inherit from alure::Decoder to make a custom decoder (DUMB for this example)
  78 class DumbDecoder : public alure::Decoder {
  79     alure::UniquePtr<std::istream> mFile;
  80     alure::UniquePtr<DUMBFILE_SYSTEM> mDfs;
  81     DUMBFILE *mDumbfile;
  82     DUH *mDuh;
  83     DUH_SIGRENDERER *mRenderer;
  84     ALuint mFrequency;
  85     alure::Vector<sample_t> mSampleBuf;
  86     uint64_t mStreamPos;
  87
  88 public:
  89     DumbDecoder(alure::UniquePtr<std::istream> file, alure::UniquePtr<DUMBFILE_SYSTEM> dfs, DUMBFILE *dfile, DUH *duh, DUH_SIGRENDERER *renderer, ALuint freq)
  90       : mFile(std::move(file)), mDfs(std::move(dfs)), mDumbfile(dfile), mDuh(duh)
  91       , mRenderer(renderer), mFrequency(freq), mStreamPos(0)
  92     { }
  93     ~DumbDecoder() override final
  94     {
  95         duh_end_sigrenderer(mRenderer);
  96         mRenderer = nullptr;
  97
  98         unload_duh(mDuh);
  99         mDuh = nullptr;
 100
 101         dumbfile_close(mDumbfile);
 102         mDumbfile = nullptr;
 103     }
 104
 105     ALuint getFrequency() const override final
 106     { return mFrequency; }
 107     alure::ChannelConfig getChannelConfig() const override final
 108     {
 109         // We always have DUMB render to stereo
 110         return alure::ChannelConfig::Stereo;
 111     }
 112     alure::SampleType getSampleType() const override final
 113     {
 114         // DUMB renders to 8.24 normalized fixed point, which we convert to
 115         // signed 16-bit samples
 116         return alure::SampleType::Int16;
 117     }
 118
 119     uint64_t getLength() const override final
 120     {
 121         // Modules have no explicit length, they just keep playing as long as
 122         // more samples get generated.
 123         return 0;
 124     }
 125
 126     uint64_t getPosition() const override final
 127     {
 128         return mStreamPos;
 129     }
 130
 131     bool seek(uint64_t) override final
 132     {
 133         // Cannot seek
 134         return false;
 135     }
 136
 137     std::pair<uint64_t,uint64_t> getLoopPoints() const override final
 138     {
 139         // No loop points
 140         return std::make_pair(0, 0);
 141     }
 142
 143     ALuint read(ALvoid *ptr, ALuint count) override final
 144     {
 145         ALuint ret = 0;
 146
 147         mSampleBuf.resize(count*2);
 148         std::array<sample_t*,1> samples{{mSampleBuf.data()}};
 149
 150         dumb_silence(samples[0], mSampleBuf.size());
 151         ret = duh_sigrenderer_generate_samples(mRenderer, 1.0f, 65536.0f/mFrequency, count,
 152                                                samples.data());
 153         for(ALuint i = 0;i < ret*2;i++)
 154         {
 155             sample_t smp = samples[0][i]>>8;
 156             if(smp < -32768) smp = -32768;
 157             else if(smp > 32767) smp = 32767;
 158             ((ALshort*)ptr)[i] = smp;
 159         }
 160         mStreamPos += ret;
 161
 162         return ret;
 163     }
 164 };
 165
 166 // Inherit from alure::DecoderFactory to use our custom decoder
 167 class DumbFactory : public alure::DecoderFactory {
 168     alure::SharedPtr<alure::Decoder> createDecoder(alure::UniquePtr<std::istream> &file) override final
 169     {
 170         static const std::array<DUH*(*)(DUMBFILE*),3> init_funcs{{
 171             dumb_read_it, dumb_read_xm, dumb_read_s3m
 172         }};
 173
 174         auto dfs = alure::MakeUnique<DUMBFILE_SYSTEM>();
 175         dfs->open = nullptr;
 176         dfs->skip = cb_skip;
 177         dfs->getc = cb_read_char;
 178         dfs->getnc = cb_read;
 179         dfs->close = nullptr;
 180         dfs->seek = cb_seek;
 181         dfs->get_size = cb_get_size;
 182
 183         DUMBFILE *dfile = dumbfile_open_ex(file.get(), dfs.get());
 184         if(!dfile) return nullptr;
 185
 186         ALuint freq = alure::Context::GetCurrent()->getDevice()->getFrequency();
 187         DUH_SIGRENDERER *renderer;
 188         DUH *duh;
 189
 190         for(auto init : init_funcs)
 191         {
 192             if((duh=init(dfile)) != nullptr)
 193             {
 194                 if((renderer=duh_start_sigrenderer(duh, 0, 2, 0)) != nullptr)
 195                     return alure::MakeShared<DumbDecoder>(
 196                         std::move(file), std::move(dfs), dfile, duh, renderer, freq
 197                     );
 198
 199                 unload_duh(duh);
 200                 duh = nullptr;
 201             }
 202
 203             dumbfile_seek(dfile, 0, SEEK_SET);
 204         }
 205
 206         if((duh=dumb_read_mod(dfile, 1)) != nullptr)
 207         {
 208             if((renderer=duh_start_sigrenderer(duh, 0, 2, 0)) != nullptr)
 209                 return alure::MakeShared<DumbDecoder>(
 210                     std::move(file), std::move(dfs), dfile, duh, renderer, freq
 211                 );
 212
 213             unload_duh(duh);
 214             duh = nullptr;
 215         }
 216
 217         dumbfile_close(dfile);
 218         return nullptr;
 219     }
 220 };
 221
 222 } // namespace
 223
 224
 225 int main(int argc, char *argv[])
 226 {
 227     // Set our custom factory for decoding modules.
 228     alure::RegisterDecoder("dumb", alure::MakeUnique<DumbFactory>());
 229
 230     alure::DeviceManager &devMgr = alure::DeviceManager::get();
 231
 232     alure::Device *dev = devMgr.openPlayback();
 233     std::cout<< "Opened \""<<dev->getName()<<"\"" <<std::endl;
 234
 235     alure::Context *ctx = dev->createContext();
 236     alure::Context::MakeCurrent(ctx);
 237
 238     for(int i = 1;i < argc;i++)
 239     {
 240         alure::SharedPtr<alure::Decoder> decoder(ctx->createDecoder(argv[i]));
 241         alure::Source *source = ctx->createSource();
 242         source->play(decoder, 32768, 4);
 243         std::cout<< "Playing "<<argv[i]<<" ("<<alure::GetSampleTypeName(decoder->getSampleType())<<", "
 244                                              <<alure::GetChannelConfigName(decoder->getChannelConfig())<<", "
 245                                              <<decoder->getFrequency()<<"hz)" <<std::endl;
 246
 247         float invfreq = 1.0f / decoder->getFrequency();
 248         while(source->isPlaying())
 249         {
 250             std::cout<< "\r "<<std::setiosflags(std::ios::fixed)<<std::setprecision(2)<<
 251                         (source->getOffset()*invfreq)<<" / "<<(decoder->getLength()*invfreq);
 252             std::cout.flush();
 253             std::this_thread::sleep_for(std::chrono::milliseconds(25));
 254             ctx->update();
 255         }
 256         std::cout<<std::endl;
 257
 258         source->release();
 259         source = nullptr;
 260         decoder.reset();
 261     }
 262
 263     alure::Context::MakeCurrent(nullptr);
 264     ctx->destroy();
 265     ctx = 0;
 266     dev->close();
 267     dev = 0;
 268
 269     return 0;
 270 }