/*----------------------------------------------------------------------------
 *
 * File:
 * eas_fmsynth.h
 *
 * Contents and purpose:
 * Implements the FM synthesizer functions.
 *
 * Copyright Sonic Network Inc. 2004

 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *----------------------------------------------------------------------------
 * Revision Control:
 *   $Revision: 90 $
 *   $Date: 2006-07-11 20:18:13 -0700 (Tue, 11 Jul 2006) $
 *----------------------------------------------------------------------------
*/

#ifndef fmsynthH
#define fmsynthH

#include "eas_data.h"

#if defined (_FM_SYNTH)

/* FM envelope state */
typedef enum {
	eFMEnvelopeStateAttack = 0,
	eFMEnvelopeStateDecay,
	eFMEnvelopeStateSustain,
	eFMEnvelopeStateRelease,
	eFMEnvelopeStateMuted,
	eFMEnvelopeStateInvalid			/* should never be in this state! */
} E_FM_ENVELOPE_STATE;

/*------------------------------------
 * S_OPERATOR data structure
 *------------------------------------
*/
typedef struct s_operator_tag
{
	EAS_I16		pitch;				/* operator pitch in cents */
    EAS_U16		envGain;			/* envelope target */
    EAS_I16		baseGain;			/* patch gain (inc. vel & key scale) */
    EAS_U16		outputGain;			/* current output gain */
    EAS_U16		envRate;			/* calculated envelope rate */
    EAS_U8		envState;			/* envelope state */
    EAS_U8		pad;				/* pad to 16-bits */
} S_OPERATOR;
#endif

typedef struct s_fm_voice_tag
{
	S_OPERATOR			oper[4];		/* operator data */
    EAS_I16				voiceGain;		/* LFO + channel parameters */
	EAS_U16				lfoPhase;		/* LFO current phase */
	EAS_I16				lfoValue;		/* LFO current value */
	EAS_U16				lfoDelay;		/* keeps track of elapsed delay time */
	EAS_I8				pan;			/* stereo pan value (-64 to +64) */
	EAS_I8				pad;			/* reserved to maintain alignment */
} S_FM_VOICE;

#ifdef _FM_EDITOR
extern S_FM_REGION newPatch;
extern S_FM_REGION OriginalPatch;
#endif

extern EAS_U32 freqTable[];

#endif