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Fix a couple of minor cases of extra precision in LFO implementation
author Michael Pavone <pavone@retrodev.com>
date Tue, 26 Mar 2019 22:27:23 -0700
parents 5278b6e44fc1
children a851d36e24bb
comparison
equal deleted inserted replaced
1801:2efdace4fb8a 1802:1d1198f16279
517 } 517 }
518 env += operator->total_level; 518 env += operator->total_level;
519 if (operator->am) { 519 if (operator->am) {
520 uint16_t base_am = (context->lfo_am_step & 0x80 ? context->lfo_am_step : ~context->lfo_am_step) & 0x7E; 520 uint16_t base_am = (context->lfo_am_step & 0x80 ? context->lfo_am_step : ~context->lfo_am_step) & 0x7E;
521 if (ams_shift[chan->ams] >= 0) { 521 if (ams_shift[chan->ams] >= 0) {
522 env += base_am >> ams_shift[chan->ams]; 522 env += (base_am >> ams_shift[chan->ams]) & MAX_ENVELOPE;
523 } else { 523 } else {
524 env += base_am << (-ams_shift[chan->ams]); 524 env += base_am << (-ams_shift[chan->ams]);
525 } 525 }
526 } 526 }
527 if (env > MAX_ENVELOPE) { 527 if (env > MAX_ENVELOPE) {
685 index ^= 1; 685 index ^= 1;
686 } 686 }
687 inc = context->ch3_supp[index].fnum; 687 inc = context->ch3_supp[index].fnum;
688 if (channel->pms) { 688 if (channel->pms) {
689 inc = inc * 2 + lfo_pm_table[(inc & 0x7F0) * 16 + channel->pms + context->lfo_pm_step]; 689 inc = inc * 2 + lfo_pm_table[(inc & 0x7F0) * 16 + channel->pms + context->lfo_pm_step];
690 inc &= 0xFFF;
690 } 691 }
691 if (!context->ch3_supp[index].block) { 692 if (!context->ch3_supp[index].block) {
692 inc >>= 1; 693 inc >>= 1;
693 } else { 694 } else {
694 inc <<= (context->ch3_supp[index].block-1); 695 inc <<= (context->ch3_supp[index].block-1);
853 case REG_ATTACK_KS: 854 case REG_ATTACK_KS:
854 operator->key_scaling = 3 - (value >> 6); 855 operator->key_scaling = 3 - (value >> 6);
855 operator->rates[PHASE_ATTACK] = value & 0x1F; 856 operator->rates[PHASE_ATTACK] = value & 0x1F;
856 break; 857 break;
857 case REG_DECAY_AM: 858 case REG_DECAY_AM:
858 //TODO: AM flag for LFO
859 operator->am = value & 0x80; 859 operator->am = value & 0x80;
860 operator->rates[PHASE_DECAY] = value & 0x1F; 860 operator->rates[PHASE_DECAY] = value & 0x1F;
861 break; 861 break;
862 case REG_SUSTAIN_RATE: 862 case REG_SUSTAIN_RATE:
863 operator->rates[PHASE_SUSTAIN] = value & 0x1F; 863 operator->rates[PHASE_SUSTAIN] = value & 0x1F;