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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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20
src/engine/platform/saa.cpp
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@ -19,6 +19,7 @@
#include "saa.h"
#include "../engine.h"
#include "../bsr.h"
#include "sound/saa1099.h"
#include <string.h>
#include <math.h>
@ -155,22 +156,9 @@ void DivPlatformSAA1099::tick(bool sysTick) {
if (chan[i].freqChanged || chan[i].keyOn || chan[i].keyOff) {
chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,chan[i].fixedArp?chan[i].baseNoteOverride:chan[i].arpOff,chan[i].fixedArp,true,0,chan[i].pitch2,chipClock,CHIP_DIVIDER);
if (chan[i].freq>65535) chan[i].freq=65535;
if (chan[i].freq>=32768) {
chan[i].freqH=7;
} else if (chan[i].freq>=16384) {
chan[i].freqH=6;
} else if (chan[i].freq>=8192) {
chan[i].freqH=5;
} else if (chan[i].freq>=4096) {
chan[i].freqH=4;
} else if (chan[i].freq>=2048) {
chan[i].freqH=3;
} else if (chan[i].freq>=1024) {
chan[i].freqH=2;
} else if (chan[i].freq>=512) {
chan[i].freqH=1;
} else {
chan[i].freqH=0;
chan[i].freqH=0;
if (chan[i].freq>511) {
chan[i].freqH=bsr((unsigned short)chan[i].freq)-9;
}
chan[i].freqL=0xff-(chan[i].freq>>chan[i].freqH);
chan[i].freqH=7-chan[i].freqH;