diff options
Diffstat (limited to 'libopna')
| -rw-r--r-- | libopna/opnafm.c | 95 | ||||
| -rw-r--r-- | libopna/opnafm.h | 3 |
2 files changed, 82 insertions, 16 deletions
diff --git a/libopna/opnafm.c b/libopna/opnafm.c index 437fcdc..3f5367f 100644 --- a/libopna/opnafm.c +++ b/libopna/opnafm.c @@ -2,6 +2,13 @@ #include "opnatables.h" +#define LIBOPNA_ENABLE_HIRES_SIN +#define LIBOPNA_ENABLE_HIRES_ENV + +enum { + ENV_MAX_HIRES = LIBOPNA_FM_ENV_MAX * 4 +}; + enum { CH3_MODE_NORMAL = 0, CH3_MODE_CSM = 1, @@ -10,7 +17,8 @@ enum { static void opna_fm_slot_reset(struct opna_fm_slot *slot) { slot->phase = 0; - slot->env = 1023; + slot->env = LIBOPNA_FM_ENV_MAX; + slot->env_hires = ENV_MAX_HIRES; slot->env_count = 0; slot->env_state = ENV_RELEASE; slot->rate_shifter = 0; @@ -60,9 +68,18 @@ void opna_fm_reset(struct opna_fm *fm) { } fm->mask = 0; } -#define LIBOPNA_ENABLE_HIRES // maximum output: 2042<<2 = 8168 static int16_t opna_fm_slotout(struct opna_fm_slot *slot, int16_t modulation) { +#ifdef LIBOPNA_ENABLE_HIRES_SIN + unsigned pind_hires = (slot->phase >> 8); + pind_hires += modulation << 1; + bool minus = pind_hires & (1<<(LOGSINTABLEHIRESBIT+1)); + bool reverse = pind_hires & (1<<LOGSINTABLEHIRESBIT); + if (reverse) pind_hires = ~pind_hires; + pind_hires &= (1<<LOGSINTABLEHIRESBIT)-1; + + int logout = logsintable_hires[pind_hires]; +#else unsigned pind = (slot->phase >> 10); pind += modulation >> 1; bool minus = pind & (1<<(LOGSINTABLEBIT+1)); @@ -70,18 +87,14 @@ static int16_t opna_fm_slotout(struct opna_fm_slot *slot, int16_t modulation) { if (reverse) pind = ~pind; pind &= (1<<LOGSINTABLEBIT)-1; -#ifdef LIBOPNA_ENABLE_HIRES - unsigned pind_hires = (slot->phase >> 8); - pind_hires += modulation << 1; - minus = pind_hires & (1<<(LOGSINTABLEHIRESBIT+1)); - reverse = pind_hires & (1<<LOGSINTABLEHIRESBIT); - if (reverse) pind_hires = ~pind_hires; - pind_hires &= (1<<LOGSINTABLEHIRESBIT)-1; - - int logout = logsintable_hires[pind_hires] + (slot->env << 2) + (slot->tl << 5); + int logout = logsintable[pind]; +#endif // LIBOPNA_ENABLE_HIRES_SIN +#ifdef LIBOPNA_ENABLE_HIRES_ENV + logout += slot->env_hires; #else - int logout = logsintable[pind] + (slot->env << 2) + (slot->tl << 5); -#endif // LIBOPNA_ENABLE_HIRES + logout += (slot->env << 2); +#endif + logout += (slot->tl << 5); int selector = logout & ((1<<EXPTABLEBIT)-1); int shifter = logout >> EXPTABLEBIT; @@ -226,6 +239,9 @@ static void opna_fm_slot_setrate(struct opna_fm_slot *slot, int status) { int rate = 2*r + (slot->keycode >> (3 - slot->ks)); if (rate > 63) rate = 63; +#ifdef LIBOPNA_ENABLE_HIRES_ENV + rate += 8; +#endif int rate_shifter = 11 - (rate >> 2); if (rate_shifter < 0) { slot->rate_selector = (rate & ((1<<2)-1)) + 4; @@ -245,10 +261,56 @@ static void opna_fm_slot_env(struct opna_fm_slot *slot) { int env_inc = rateinctable[slot->rate_selector][rate_index]; env_inc *= slot->rate_mul; +#ifdef LIBOPNA_ENABLE_HIRES_ENV switch (slot->env_state) { int newenv; int sl; case ENV_ATTACK: + newenv = slot->env_hires + (((-slot->env_hires-1) * env_inc) >> 6); + if (newenv <= 0) { + slot->env_hires = 0; + slot->env_state = ENV_DECAY; + opna_fm_slot_setrate(slot, ENV_DECAY); + } else { + slot->env_hires = newenv; + } + break; + case ENV_DECAY: + slot->env_hires += env_inc; + sl = slot->sl; + if (sl == 0xf) sl = 0x1f; + if (slot->env_hires >= (sl << 7)) { + slot->env_state = ENV_SUSTAIN; + opna_fm_slot_setrate(slot, ENV_SUSTAIN); + } + break; + case ENV_SUSTAIN: + slot->env_hires += env_inc; + if (slot->env_hires >= ENV_MAX_HIRES) slot->env_hires = ENV_MAX_HIRES; + break; + case ENV_RELEASE: + slot->env_hires += env_inc; + if (slot->env_hires >= ENV_MAX_HIRES) { + slot->env_hires = ENV_MAX_HIRES; + slot->env_state = ENV_OFF; + } + break; + } + slot->env = slot->env_hires >> 2; +#else // LIBOPNA_ENABLE_HIRES_ENV + switch (slot->env_state) { + int newenv; + int sl; + case ENV_ATTACK: + newenv = slot->env_hires + (((-slot->env-1) * env_inc) >> 6); + if (newenv <= 0) { + slot->env = 0; + slot->env_hires = 0; + slot->env_state = ENV_DECAY; + opna_fm_slot_setrate(slot, ENV_DECAY); + } else { + slot->env_hires = newenv; + } newenv = slot->env + (((-slot->env-1) * env_inc) >> 4); if (newenv <= 0) { slot->env = 0; @@ -269,16 +331,17 @@ static void opna_fm_slot_env(struct opna_fm_slot *slot) { break; case ENV_SUSTAIN: slot->env += env_inc; - if (slot->env >= 1023) slot->env = 1023; + if (slot->env >= LIBOPNA_FM_ENV_MAX) slot->env = LIBOPNA_FM_ENV_MAX; break; case ENV_RELEASE: slot->env += env_inc; - if (slot->env >= 1023) { - slot->env = 1023; + if (slot->env >= LIBOPNA_FM_ENV_MAX) { + slot->env = LIBOPNA_FM_ENV_MAX; slot->env_state = ENV_OFF; } break; } +#endif } } diff --git a/libopna/opnafm.h b/libopna/opnafm.h index cf4fff5..1a7f55a 100644 --- a/libopna/opnafm.h +++ b/libopna/opnafm.h @@ -8,6 +8,7 @@ extern "C" { #endif +#define LIBOPNA_FM_ENV_MAX 1023 enum { ENV_ATTACK, ENV_DECAY, @@ -21,6 +22,8 @@ struct opna_fm_slot { uint32_t phase; // 10 bits uint16_t env; + // 12 bits + uint16_t env_hires; uint16_t env_count; uint8_t env_state; uint8_t rate_shifter; |