(This function is part of SDL_mixer, a separate library from SDL.)

MIX_CreateSineWaveAudio

Create a MIX_Audio that generates a sinewave.

Header File

Syntax

MIX_Audio * MIX_CreateSineWaveAudio(MIX_Mixer *mixer, int hz, float amplitude, Sint64 ms);

Function Parameters

MIX_Mixer *	mixer	a mixer this audio is intended to be used with. May be NULL.
int	hz	the sinewave's frequency in Hz.
float	amplitude	the sinewave's amplitude from 0.0f to 1.0f.
Sint64	ms	the maximum number of milliseconds of audio to generate, or less than zero to generate infinite audio.

Return Value

(MIX_Audio *) Returns an audio object that can be used to make sound on a mixer, or NULL on failure; call SDL_GetError() for more information.

Remarks

This is useful just to have something to play, perhaps for testing or debugging purposes.

You specify its frequency in Hz (determines the pitch of the sinewave's audio) and amplitude (determines the volume of the sinewave: 1.0f is very loud, 0.0f is silent).

A number of milliseconds of audio to generate can be specified. Specifying a value less than zero will generate infinite audio (when assigned to a MIX_Track, the sinewave will play forever).

MIX_Audio objects can be shared between multiple mixers. The mixer parameter just suggests the most likely mixer to use this audio, in case some optimization might be applied, but this is not required, and a NULL mixer may be specified.

Thread Safety

It is safe to call this function from any thread.

Version

This function is available since SDL_mixer 3.0.0.