arts/flow/gsl/gslosctable.h

/* GSL - Generic Sound Layer
 * Copyright (C) 2001-2002 Tim Janik
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */
#ifndef __GSL_OSC_TABLE_H__
#define __GSL_OSC_TABLE_H__

#include <gsl/gsldefs.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */


/* --- structures & enums --- */
typedef enum    /*< skip >*/
{
  GSL_OSC_WAVE_NONE,
  GSL_OSC_WAVE_SINE,
  GSL_OSC_WAVE_TRIANGLE,
  GSL_OSC_WAVE_SAW_RISE,
  GSL_OSC_WAVE_SAW_FALL,
  GSL_OSC_WAVE_PEAK_RISE,
  GSL_OSC_WAVE_PEAK_FALL,
  GSL_OSC_WAVE_MOOG_SAW,
  GSL_OSC_WAVE_SQUARE,
  GSL_OSC_WAVE_PULSE_SAW
} GslOscWaveForm;

typedef struct
{
  gfloat         mix_freq;
  GslOscWaveForm wave_form;
  gpointer       entry_array;
} GslOscTable;

typedef struct
{
  gfloat        min_freq;
  gfloat        max_freq;
  guint         n_values;
  const gfloat *values;	/* tqcontains n_values+1 values with values[0]==values[n_values] */
  /* integer stepping (block size dependant) */
  guint32	n_frac_bits;
  guint32	frac_bittqmask;
  gfloat	freq_to_step;		/* freq -> int.frac */
  gfloat	phase_to_pos;		/* 0..1 -> int.frac */
  gfloat	ifrac_to_float;		/* frac -> 0..1 float */
  guint		min_pos, max_pos;	/* pulse extension */
} GslOscWave;


/* --- oscillator table --- */
GslOscTable*    gsl_osc_table_create            (gfloat                  mix_freq,
						 GslOscWaveForm          wave_form,
						 double                (*filter_func) (double),
						 guint                   n_freqs,
						 const gfloat           *freqs);
void            gsl_osc_table_lookup            (const GslOscTable      *table,
						 gfloat                  freq,
						 GslOscWave             *wave);
void            gsl_osc_table_free              (GslOscTable            *table);


/* --- oscillator wave utils --- */
void            gsl_osc_wave_fill_buffer        (GslOscWaveForm          type,
						 guint                   n_values,
						 gfloat                 *values);
void		gsl_osc_wave_extrema		(guint                   n_values,
						 const gfloat		*values,
						 gfloat			*min,
						 gfloat			*max);
void		gsl_osc_wave_normalize		(guint			 n_values,
						 gfloat			*values,
						 gfloat			 new_center,
						 gfloat			 new_max);
void		gsl_osc_wave_adjust_range	(guint			 n_values,
						 gfloat			*values,
						 gfloat			 min,
						 gfloat			 max,
						 gfloat			 new_center,
						 gfloat			 new_max);



#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif /* __GSL_OSC_TABLE_H__ */