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Nuked OPN2: optimize detune calculation

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This commit is contained in:
nukeykt 2017-09-28 19:54:12 +09:00
parent 6a23a42540
commit 27a77147aa
1 changed files with 2 additions and 2 deletions
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4
core/sound/ym3438.c
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@ -506,7 +506,7 @@ void OPN2_PhaseCalcIncrement(ym3438_t *chip)
basefreq = (fnum << chip->pg_block) >> 2;
/* Apply detune */
if (dt & 0x03)
if (dt_l)
{
if (kcode > 0x1c)
{
@ -514,7 +514,7 @@ void OPN2_PhaseCalcIncrement(ym3438_t *chip)
}
block = kcode >> 2;
note = kcode & 0x03;
sum = block + 1 + ((dt_l == 3) | (dt_l & 0x02) | ((dt_l != 0) << 3));
sum = block + 9 + ((dt_l == 3) | (dt_l & 0x02));
sum_h = sum >> 1;
sum_l = sum & 0x01;
detune = pg_detune[(sum_l << 2) | note] >> (9 - sum_h);