// --------------------------------------------------------------
// --------------------------------------------------------------
#ifndef _LFO_H_
#define	_LFO_H_

#include "synth_defs.h"
#include "noise.h"

#define LFO_SH_ALPHA		0.002		// S&H smoothing
#define LFO_KE			((synth_float_t)(1-exp(-1)))

// --------------------------------------------------------------
// Types
// --------------------------------------------------------------
enum
{	
	LFO_WAVEFORM_SINE,
	LFO_WAVEFORM_COSINE,
	LFO_WAVEFORM_SAW,
	LFO_WAVEFORM_SQUARE,
	LFO_WAVEFORM_TRIANGLE,
	LFO_WAVEFORM_SH_UNI,
	LFO_WAVEFORM_SH_GAUSS,
	LFO_WAVEFORM_ONE_MINUS_SINE,
	LFO_WAVEFORM_ONE_MINUS_COSINE,
	LFO_WAVEFORM_ONE_MINUS_SAW,
	LFO_WAVEFORM_ONE_MINUS_SQUARE,
	LFO_WAVEFORM_ONE_MINUS_TRIANGLE,
	LFO_NUM_WAVEFORMS
};

enum
{
	LFO_PARAM2_WAVEFORM,
	LFO_PARAM2_FREQ,
	LFO_PARAM2_SMOOTH,
	LFO_PARAM2_DELAY,
	LFO_PARAM2_ATTACK,
	LFO_PARAM2_SYMMETRY,
	LFO_NUM_PARAMS
};

typedef struct _slfo_t
{
	synth_float_t param[LFO_NUM_PARAMS];
	synth_float_t fs;
	synth_float_t a, b, y[2], x, dx, out, sh_sample, tri;
	int freq_update_req, sqr;
	synth_float_t *pOut;
	UINT32 bufsize;
	noise_gen_t noise;
	synth_float_t smooth_a, smooth_b;
	UINT32 smooth_is_negative;
	synth_float_t delay_x, delay_dx, attack_y, attack_a;
	synth_float_t gain, offset;

} lfo_t;

// --------------------------------------------------------------
#if defined(__cplusplus)
extern "C" {
#endif

// --------------------------------------------------------------
// Exported functions
// --------------------------------------------------------------
void LFO_Init(lfo_t *pObj, synth_float_t fs);
void LFO_Free(lfo_t *pObj);
void LFO_SetFS(lfo_t *pObj, synth_float_t fs);
void LFO_SetBufsize(lfo_t *pObj, UINT32 bufsize);
void LFO_Reset(lfo_t *pObj, synth_float_t initial_phase);
void LFO_Param2Set(lfo_t *pObj, UINT32 type, synth_float_t value);
synth_float_t* LFO_ProcessDataV(lfo_t *pObj, UINT32 len);

#if defined(__cplusplus)
}

#endif
// --------------------------------------------------------------

#endif // _LFO_H_