From 68c03edbb563983b6ac3e81a826871bfdf9e3bd4 Mon Sep 17 00:00:00 2001 From: Vitaly Novichkov Date: Thu, 13 Dec 2018 02:28:57 +0300 Subject: Build: Splid the main CMake build script Keep it have library code only but no utils and examples are will be built independently #196 --- examples/sdl2_audio/sdl2_sample.c | 124 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 examples/sdl2_audio/sdl2_sample.c (limited to 'examples/sdl2_audio/sdl2_sample.c') diff --git a/examples/sdl2_audio/sdl2_sample.c b/examples/sdl2_audio/sdl2_sample.c new file mode 100644 index 0000000..b6307d7 --- /dev/null +++ b/examples/sdl2_audio/sdl2_sample.c @@ -0,0 +1,124 @@ +#include +#include + +/* prototype for our audio callback */ +/* see the implementation for more information */ +void my_audio_callback(void *midi_player, Uint8 *stream, int len); + +/* variable declarations */ +static Uint32 is_playing = 0; /* remaining length of the sample we have to play */ +static short buffer[4096]; /* Audio buffer */ + + +int main(int argc, char *argv[]) +{ + /* local variables */ + static SDL_AudioSpec spec; /* the specs of our piece of music */ + static struct ADL_MIDIPlayer *midi_player = NULL; /* Instance of ADLMIDI player */ + static const char *music_path = NULL; /* Path to music file */ + + if (argc < 2) + { + fprintf(stderr, "\n" + "\n" + "No given files to play!\n" + "\n" + "Syntax: %s \n" + "\n", argv[0]); + return 2; + } + + music_path = argv[1]; + + /* Initialize SDL.*/ + if(SDL_Init(SDL_INIT_AUDIO) < 0) + return 1; + + spec.freq = 44100; + spec.format = AUDIO_S16SYS; + spec.channels = 2; + spec.samples = 2048; + + /* Initialize ADLMIDI */ + midi_player = adl_init(spec.freq); + if (!midi_player) + { + fprintf(stderr, "Couldn't initialize ADLMIDI: %s\n", adl_errorString()); + return 1; + } + + /* set the callback function */ + spec.callback = my_audio_callback; + /* set ADLMIDI's descriptor as userdata to use it for sound generation */ + spec.userdata = midi_player; + + /* Open the audio device */ + if (SDL_OpenAudio(&spec, NULL) < 0) + { + fprintf(stderr, "Couldn't open audio: %s\n", SDL_GetError()); + return 1; + } + + /* Optionally Setup ADLMIDI as you want */ + + /* Set using of embedded bank by ID */ + /*adl_setBank(midi_player, 68);*/ + + /* Set using of custom bank (WOPL format) loaded from a file */ + /*adl_openBankFile(midi_player, "/home/vitaly/Yandex.Disk/Музыка/Wolfinstein.wopl");*/ + + /* Open the MIDI (or MUS, IMF or CMF) file to play */ + if (adl_openFile(midi_player, music_path) < 0) + { + fprintf(stderr, "Couldn't open music file: %s\n", adl_errorInfo(midi_player)); + SDL_CloseAudio(); + adl_close(midi_player); + return 1; + } + + is_playing = 1; + /* Start playing */ + SDL_PauseAudio(0); + + printf("Playing... Hit Ctrl+C to quit!\n"); + + /* wait until we're don't playing */ + while (is_playing) + { + SDL_Delay(100); + } + + /* shut everything down */ + SDL_CloseAudio(); + adl_close(midi_player); + + return 0; +} + +/* + audio callback function + here you have to copy the data of your audio buffer into the + requesting audio buffer (stream) + you should only copy as much as the requested length (len) +*/ +void my_audio_callback(void *midi_player, Uint8 *stream, int len) +{ + struct ADL_MIDIPlayer* p = (struct ADL_MIDIPlayer*)midi_player; + + /* Convert bytes length into total count of samples in all channels */ + int samples_count = len / 2; + + /* Take some samples from the ADLMIDI */ + samples_count = adl_play(p, samples_count, (short*)buffer); + + if(samples_count <= 0) + { + is_playing = 0; + SDL_memset(stream, 0, len); + return; + } + + /* Send buffer to the audio device */ + SDL_memcpy(stream, (Uint8*)buffer, samples_count * 2); +} + -- cgit v1.2.3