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Diffstat (limited to 'sound/softsynth/opl/opl_inc.h')
| -rw-r--r-- | sound/softsynth/opl/opl_inc.h | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/sound/softsynth/opl/opl_inc.h b/sound/softsynth/opl/opl_inc.h new file mode 100644 index 0000000000..0798bd9f6a --- /dev/null +++ b/sound/softsynth/opl/opl_inc.h @@ -0,0 +1,196 @@ +/* + * Copyright (C) 2002-2009 The DOSBox Team + * OPL2/OPL3 emulation library + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser 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 + */ + + +/* + * Originally based on ADLIBEMU.C, an AdLib/OPL2 emulation library by Ken Silverman + * Copyright (C) 1998-2001 Ken Silverman + * Ken Silverman's official web site: "http://www.advsys.net/ken" + */ + +#define fltype double + +/* + define Bits, Bitu, Bit32s, Bit32u, Bit16s, Bit16u, Bit8s, Bit8u here +*/ + +#define Bitu uint +#define Bits int +#define Bit32u uint32 +#define Bit32s int32 +#define Bit16u uint16 +#define Bit16s int16 +#define Bit8u uint8 +#define Bit8s int8 + +#undef NUM_CHANNELS +#if defined(OPLTYPE_IS_OPL3) +#define NUM_CHANNELS 18 +#else +#define NUM_CHANNELS 9 +#endif + +#define MAXOPERATORS (NUM_CHANNELS*2) + + +#define FL05 ((fltype)0.5) +#define FL2 ((fltype)2.0) + +#ifdef PI +#undef PI +#endif + +#define PI ((fltype)3.1415926535897932384626433832795) + + +#define FIXEDPT 0x10000 // fixed-point calculations using 16+16 +#define FIXEDPT_LFO 0x1000000 // fixed-point calculations using 8+24 + +#define WAVEPREC 1024 // waveform precision (10 bits) + +#define INTFREQU ((fltype)(14318180.0 / 288.0)) // clocking of the chip + + +#define OF_TYPE_ATT 0 +#define OF_TYPE_DEC 1 +#define OF_TYPE_REL 2 +#define OF_TYPE_SUS 3 +#define OF_TYPE_SUS_NOKEEP 4 +#define OF_TYPE_OFF 5 + +#define ARC_CONTROL 0x00 +#define ARC_TVS_KSR_MUL 0x20 +#define ARC_KSL_OUTLEV 0x40 +#define ARC_ATTR_DECR 0x60 +#define ARC_SUSL_RELR 0x80 +#define ARC_FREQ_NUM 0xa0 +#define ARC_KON_BNUM 0xb0 +#define ARC_PERC_MODE 0xbd +#define ARC_FEEDBACK 0xc0 +#define ARC_WAVE_SEL 0xe0 + +#define ARC_SECONDSET 0x100 // second operator set for OPL3 + + +#define OP_ACT_OFF 0x00 +#define OP_ACT_NORMAL 0x01 // regular channel activated (bitmasked) +#define OP_ACT_PERC 0x02 // percussion channel activated (bitmasked) + +#define BLOCKBUF_SIZE 512 + + +// vibrato constants +#define VIBTAB_SIZE 8 +#define VIBFAC 70/50000 // no braces, integer mul/div + +// tremolo constants and table +#define TREMTAB_SIZE 53 +#define TREM_FREQ ((fltype)(3.7)) // tremolo at 3.7hz + + +/* operator struct definition + For OPL2 all 9 channels consist of two operators each, carrier and modulator. + Channel x has operators x as modulator and operators (9+x) as carrier. + For OPL3 all 18 channels consist either of two operators (2op mode) or four + operators (4op mode) which is determined through register4 of the second + adlib register set. + Only the channels 0,1,2 (first set) and 9,10,11 (second set) can act as + 4op channels. The two additional operators for a channel y come from the + 2op channel y+3 so the operatorss y, (9+y), y+3, (9+y)+3 make up a 4op + channel. +*/ +typedef struct operator_struct { + Bit32s cval, lastcval; // current output/last output (used for feedback) + Bit32u tcount, wfpos, tinc; // time (position in waveform) and time increment + fltype amp, step_amp; // and amplification (envelope) + fltype vol; // volume + fltype sustain_level; // sustain level + Bit32s mfbi; // feedback amount + fltype a0, a1, a2, a3; // attack rate function coefficients + fltype decaymul, releasemul; // decay/release rate functions + Bit32u op_state; // current state of operator (attack/decay/sustain/release/off) + Bit32u toff; + Bit32s freq_high; // highest three bits of the frequency, used for vibrato calculations + Bit16s* cur_wform; // start of selected waveform + Bit32u cur_wmask; // mask for selected waveform + Bit32u act_state; // activity state (regular, percussion) + bool sus_keep; // keep sustain level when decay finished + bool vibrato,tremolo; // vibrato/tremolo enable bits + + // variables used to provide non-continuous envelopes + Bit32u generator_pos; // for non-standard sample rates we need to determine how many samples have passed + Bits cur_env_step; // current (standardized) sample position + Bits env_step_a,env_step_d,env_step_r; // number of std samples of one step (for attack/decay/release mode) + Bit8u step_skip_pos; // position of 8-cyclic step skipping (always 2^x to check against mask) + Bits env_step_skip_a; // bitmask that determines if a step is skipped (respective bit is zero then) + +#if defined(OPLTYPE_IS_OPL3) + bool is_4op,is_4op_attached; // base of a 4op channel/part of a 4op channel + Bit32s left_pan,right_pan; // opl3 stereo panning amount +#endif +} op_type; + +// per-chip variables +Bitu chip_num; +op_type op[MAXOPERATORS]; + +Bits int_samplerate; + +Bit8u status; +Bit32u index; +#if defined(OPLTYPE_IS_OPL3) +Bit8u adlibreg[512]; // adlib register set (including second set) +Bit8u wave_sel[44]; // waveform selection +#else +Bit8u adlibreg[256]; // adlib register set +Bit8u wave_sel[22]; // waveform selection +#endif + + +// vibrato/tremolo increment/counter +Bit32u vibtab_pos; +Bit32u vibtab_add; +Bit32u tremtab_pos; +Bit32u tremtab_add; + + +// enable an operator +void enable_operator(Bitu regbase, op_type* op_pt); + +// functions to change parameters of an operator +void change_frequency(Bitu chanbase, Bitu regbase, op_type* op_pt); + +void change_attackrate(Bitu regbase, op_type* op_pt); +void change_decayrate(Bitu regbase, op_type* op_pt); +void change_releaserate(Bitu regbase, op_type* op_pt); +void change_sustainlevel(Bitu regbase, op_type* op_pt); +void change_waveform(Bitu regbase, op_type* op_pt); +void change_keepsustain(Bitu regbase, op_type* op_pt); +void change_vibrato(Bitu regbase, op_type* op_pt); +void change_feedback(Bitu chanbase, op_type* op_pt); + +// general functions +void adlib_init(Bit32u samplerate); +void adlib_write(Bitu idx, Bit8u val); +void adlib_getsample(Bit16s* sndptr, Bits numsamples); + +Bitu adlib_reg_read(Bitu port); +void adlib_write_index(Bitu port, Bit8u val); + +static Bit32u generator_add; // should be a chip parameter |