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/*
Demonstrates playback of a sine wave.
Since all this example is doing is playing back a sine wave, we can disable decoding (and encoding) which will slightly
reduce the size of the executable. This is done with the `MA_NO_DECODING` and `MA_NO_ENCODING` options.
The generation of sine wave is achieved via the `ma_waveform` API. A waveform is a data source which means it can be
seamlessly plugged into the `ma_data_source_*()` family of APIs as well.
A waveform is initialized using the standard config/init pattern used throughout all of miniaudio. Frames are read via
the `ma_waveform_read_pcm_frames()` API.
This example works with Emscripten.
*/
#define MA_NO_DECODING
#define MA_NO_ENCODING
#include "../miniaudio.c"
#include <stdio.h>
#ifdef __EMSCRIPTEN__
#include <emscripten.h>
void main_loop__em()
{
}
#endif
#define DEVICE_FORMAT ma_format_f32
#define DEVICE_CHANNELS 2
#define DEVICE_SAMPLE_RATE 48000
void data_callback(ma_device* pDevice, void* pOutput, const void* pInput, ma_uint32 frameCount)
{
ma_waveform_read_pcm_frames((ma_waveform*)pDevice->pUserData, pOutput, frameCount, NULL);
(void)pInput; /* Unused. */
}
int main(int argc, char** argv)
{
ma_waveform sineWave;
ma_device_config deviceConfig;
ma_device device;
ma_waveform_config sineWaveConfig;
deviceConfig = ma_device_config_init(ma_device_type_playback);
deviceConfig.playback.format = DEVICE_FORMAT;
deviceConfig.playback.channels = DEVICE_CHANNELS;
deviceConfig.sampleRate = DEVICE_SAMPLE_RATE;
deviceConfig.dataCallback = data_callback;
deviceConfig.pUserData = &sineWave;
if (ma_device_init(NULL, &deviceConfig, &device) != MA_SUCCESS) {
printf("Failed to open playback device.\n");
return -4;
}
printf("Device Name: %s\n", device.playback.name);
sineWaveConfig = ma_waveform_config_init(device.playback.format, device.playback.channels, device.sampleRate, ma_waveform_type_sine, 0.2, 220);
ma_waveform_init(&sineWaveConfig, &sineWave);
if (ma_device_start(&device) != MA_SUCCESS) {
printf("Failed to start playback device.\n");
ma_device_uninit(&device);
return -5;
}
#ifdef __EMSCRIPTEN__
emscripten_set_main_loop(main_loop__em, 0, 1);
#else
printf("Press Enter to quit...\n");
getchar();
#endif
ma_device_uninit(&device);
ma_waveform_uninit(&sineWave); /* Uninitialize the waveform after the device so we don't pull it from under the device while it's being reference in the data callback. */
(void)argc;
(void)argv;
return 0;
}
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