eas_fmengine.h revision 56c99cd2c2c1e6ab038dac5fced5b92ccf11ff6c 
1/*----------------------------------------------------------------------------
2 *
3 * File:
4 * eas_fmengine.h
5 *
6 * Contents and purpose:
7 * Declarations, interfaces, and prototypes for FM synthesize low-level.
8 *
9 * Copyright Sonic Network Inc. 2004
10
11 * Licensed under the Apache License, Version 2.0 (the "License");
12 * you may not use this file except in compliance with the License.
13 * You may obtain a copy of the License at
14 *
15 *      http://www.apache.org/licenses/LICENSE-2.0
16 *
17 * Unless required by applicable law or agreed to in writing, software
18 * distributed under the License is distributed on an "AS IS" BASIS,
19 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
20 * See the License for the specific language governing permissions and
21 * limitations under the License.
22 *
23 *----------------------------------------------------------------------------
24 * Revision Control:
25 *   $Revision: 664 $
26 *   $Date: 2007-04-25 13:11:22 -0700 (Wed, 25 Apr 2007) $
27 *----------------------------------------------------------------------------
28*/
29
30/* sentinel */
31#ifndef _FMENGINE_H
32#define _FMENGINE_H
33
34/* check for split architecture */
35#if defined (EAS_SPLIT_HYBRID_SYNTH) || defined(EAS_SPLIT_FM_SYNTH)
36#define FM_OFFBOARD
37#endif
38
39/* output level to mix buffer (3 = -24dB) */
40#define FM_GAIN_SHIFT 3
41#define FM_MONO_GAIN_SHIFT 9
42
43/* voice output level for stereo 15 = +6dB */
44#define FM_STEREO_PRE_GAIN_SHIFT 11
45#define FM_STEREO_POST_GAIN_SHIFT 10
46
47/* modulator input level shift (21 = -30dB) */
48#define FM_MODULATOR_INPUT_SHIFT 21
49
50/* feedback control level shift (7 = 0dB) */
51#define FM_FEEDBACK_SHIFT 7
52
53/* synth final output level */
54#define SYNTH_POST_GAIN_SHIFT 14
55
56/* LFO modulation to gain control */
57#define FM_LFO_GAIN_SHIFT 12
58
59/* sine table is always a power of 2 - saves cycles in inner loop */
60#define SINE_TABLE_SIZE_IN_BITS 11
61#define SINE_TABLE_SIZE 2048
62
63/* operator structure for FM engine */
64typedef struct
65{
66    EAS_U32     phase;              /* current waveform phase */
67    EAS_U16     gain;               /* current internal gain */
68    EAS_U16     outputGain;         /* current output gain */
69} S_FM_ENG_OPER;
70
71typedef struct
72{
73    S_FM_ENG_OPER   oper[4];        /* operator data */
74    EAS_I16         op1Out;         /* op1 output for feedback loop */
75    EAS_I16         op3Out;         /* op3 output for feedback loop */
76    EAS_U16         voiceGain;      /* LFO + channel parameters */
77#if (NUM_OUTPUT_CHANNELS == 2)
78    EAS_U16         gainLeft;       /* left gain multiplier */
79    EAS_U16         gainRight;      /* right gain multiplier */
80#endif
81    EAS_U8          flags;          /* mode bits and noise waveform flags */
82    EAS_U8          feedback;       /* feedback for Op1 and Op3 */
83} S_FM_ENG_VOICE;
84
85typedef struct
86{
87    EAS_U16         gain[4];        /* initial operator gain value */
88    EAS_U16         outputGain[4];  /* initial operator output gain value */
89    EAS_U16         voiceGain;      /* initial voice gain */
90    EAS_U8          flags;          /* mode bits and noise waveform flags */
91    EAS_U8          feedback;       /* feedback for Op1 and Op3 */
92#if (NUM_OUTPUT_CHANNELS == 2)
93    EAS_I8          pan;            /* pan value +/-64 */
94#endif
95} S_FM_VOICE_CONFIG;
96
97typedef struct
98{
99    EAS_U16         gain[4];        /* new operator gain value */
100    EAS_I16         pitch[4];       /* new pitch value */
101    EAS_U16         voiceGain;      /* new voice gain */
102} S_FM_VOICE_FRAME;
103
104/* bit definitions for S_FM_ENG_VOICE.flags */
105#define FLAG_FM_ENG_VOICE_OP1_NOISE     0x10    /* operator 1 source is PRNG */
106#define FLAG_FM_ENG_VOICE_OP2_NOISE     0x20    /* operator 2 source is PRNG */
107#define FLAG_FM_ENG_VOICE_OP3_NOISE     0x40    /* operator 3 source is PRNG */
108#define FLAG_FM_ENG_VOICE_OP4_NOISE     0x80    /* operator 4 source is PRNG */
109
110#ifdef FM_OFFBOARD
111extern EAS_BOOL FM_StartFrame (EAS_FRAME_BUFFER_HANDLE pFrameBuffer);
112extern EAS_BOOL FM_EndFrame (EAS_FRAME_BUFFER_HANDLE pFrameBuffe, EAS_I32 *pMixBuffer, EAS_I16 masterGain);
113#endif
114
115/* FM engine prototypes */
116extern void FM_ConfigVoice (EAS_I32 voiceNum, S_FM_VOICE_CONFIG *vCfg, EAS_FRAME_BUFFER_HANDLE pFrameBuffer);
117extern void FM_ProcessVoice (EAS_I32 voiceNum, S_FM_VOICE_FRAME *pFrame, EAS_I32 numSamplesToAdd, EAS_PCM *pTempBuffer, EAS_PCM *pBuffer, EAS_I32 *pMixBuffer, EAS_FRAME_BUFFER_HANDLE pFrameBuffer);
118
119#endif
120/* #ifndef _FMENGINE_H */
121
122