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Use bsr() in frequency shift calculations

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This commit is contained in:
Natt Akuma 2024-09-18 13:05:45 +07:00
parent 9905981e61
commit 6a58797669
6 changed files with 77 additions and 145 deletions
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77
src/engine/platform/opl.cpp
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@ -19,6 +19,7 @@
#include "opl.h"
#include "../engine.h"
#include "../bsr.h"
#include "../../ta-log.h"
#include <string.h>
#include <math.h>
@ -1386,39 +1387,12 @@ void DivPlatformOPL::tick(bool sysTick) {
double off=(s->centerRate>=1)?((double)s->centerRate/8363.0):1.0;
chan[i].freq=(int)(off*parent->calcFreq(chan[i].baseFreq,chan[i].pitch,chan[i].fixedArp?chan[i].baseNoteOverride:chan[i].arpOff,chan[i].fixedArp,false,2,chan[i].pitch2,chipClock,(524288*768)));
if (chan[i].freq<0x400) chan[i].freq=0x400;
if (chan[i].freq>0x3ffffff) chan[i].freq=0x3ffffff;
if (chan[i].freq>=0x2000000) {
chan[i].freqH=0;
if (chan[i].freq>0x3ffffff) {
chan[i].freq=0x3ffffff;
chan[i].freqH=15;
} else if (chan[i].freq>=0x1000000) {
chan[i].freqH=14;
} else if (chan[i].freq>=0x800000) {
chan[i].freqH=13;
} else if (chan[i].freq>=0x400000) {
chan[i].freqH=12;
} else if (chan[i].freq>=0x200000) {
chan[i].freqH=11;
} else if (chan[i].freq>=0x100000) {
chan[i].freqH=10;
} else if (chan[i].freq>=0x80000) {
chan[i].freqH=9;
} else if (chan[i].freq>=0x40000) {
chan[i].freqH=8;
} else if (chan[i].freq>=0x20000) {
chan[i].freqH=7;
} else if (chan[i].freq>=0x10000) {
chan[i].freqH=6;
} else if (chan[i].freq>=0x8000) {
chan[i].freqH=5;
} else if (chan[i].freq>=0x4000) {
chan[i].freqH=4;
} else if (chan[i].freq>=0x2000) {
chan[i].freqH=3;
} else if (chan[i].freq>=0x1000) {
chan[i].freqH=2;
} else if (chan[i].freq>=0x800) {
chan[i].freqH=1;
} else {
chan[i].freqH=0;
chan[i].freqH=bsr32(chan[i].freq)-11;
}
chan[i].freqL=(chan[i].freq>>chan[i].freqH)&0x3ff;
chan[i].freqH=8^chan[i].freqH;
@ -1528,44 +1502,15 @@ void DivPlatformOPL::tick(bool sysTick) {
#define OPLL_C_NUM 686
int DivPlatformOPL::octave(int freq) {
if (freq>=OPLL_C_NUM*64) {
return 128;
} else if (freq>=OPLL_C_NUM*32) {
return 64;
} else if (freq>=OPLL_C_NUM*16) {
return 32;
} else if (freq>=OPLL_C_NUM*8) {
return 16;
} else if (freq>=OPLL_C_NUM*4) {
return 8;
} else if (freq>=OPLL_C_NUM*2) {
return 4;
} else if (freq>=OPLL_C_NUM) {
return 2;
} else {
return 1;
}
return 1;
freq/=OPLL_C_NUM;
if (freq==0) return 1;
return 1<<bsr(freq);
}
int DivPlatformOPL::toFreq(int freq) {
if (freq>=OPLL_C_NUM*64) {
return 0x1c00|((freq>>7)&0x3ff);
} else if (freq>=OPLL_C_NUM*32) {
return 0x1800|((freq>>6)&0x3ff);
} else if (freq>=OPLL_C_NUM*16) {
return 0x1400|((freq>>5)&0x3ff);
} else if (freq>=OPLL_C_NUM*8) {
return 0x1000|((freq>>4)&0x3ff);
} else if (freq>=OPLL_C_NUM*4) {
return 0xc00|((freq>>3)&0x3ff);
} else if (freq>=OPLL_C_NUM*2) {
return 0x800|((freq>>2)&0x3ff);
} else if (freq>=OPLL_C_NUM) {
return 0x400|((freq>>1)&0x3ff);
} else {
return freq&0x3ff;
}
int block=freq/OPLL_C_NUM;
if (block>0) block=bsr(block);
return (block<<10)|((freq>>block)&0x3ff);
}
void DivPlatformOPL::muteChannel(int ch, bool mute) {