More general form of sine wave sample data generation

gistfile1.c

typedef struct _WaveState {
	
	double amplitude;
	double increment;
	double theta;

} WaveState;

void fillWaveSamples( WaveState * state, UInt32 number_of_samples, Float32 * buffer) {
	
	for(UInt32 i = 0; i < number_of_samples; ++i) {
		
		buffer[ i ]  = state->amplitude * sin( state->theta );
		state->theta = fmod( state->theta + state->increment, 2.0 * M_PI );
	}
}

void initialiseWave( WaveState *state, double frequency, double sample_rate, double amplitude ) {
	
	state->amplitude   = amplitude;
	state->increment   = 2.0 * M_PI * (frequency / sample_rate);
	state->theta       = 0;
}