Added a very simple pure C example

1 files changed, 124 insertions, 0 deletions

diff --git a/examples/sd2_audio/sdl2_sample.c b/examples/sd2_audio/sdl2_sample.c
new file mode 100644
index 0000000..28d2226
--- /dev/null
+++ b/examples/sd2_audio/sdl2_sample.c
@@ -0,0 +1,124 @@
+#include <SDL2/SDL.h>
+#include <adlmidi.h>
+
+/* 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 <path-to-MIDI-file>\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 || adl_atEnd(p))
+    {
+        is_playing = 0;
+        SDL_memset(stream, 0, len);
+        return;
+    }
+
+    /* Send buffer to the audio device */
+    SDL_memcpy(stream, (Uint8*)buffer, samples_count * 2);
+}
+