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KYRA: Limit octave to valid range in setupNote()

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Alexander Miller authored and athrxx committed 2020-12-19 03:15:35 +01:00
1 parent c50cf51f5e
commit 78cde14dc9
1 file changed
+8 -5
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engines/kyra/sound/drivers/adlib.cpp
+8 -5
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@@ -973,21 +973,24 @@ void AdLibDriver::setupNote(uint8 rawNote, Channel &channel, bool flag) {
if (channel.pitchBend || flag) {
const uint8 *table;
// For safety, limit the values used to index the tables.
uint8 baseNote = CLIP(rawNote & 0x0F, 0, 11);
uint8 indexNote = CLIP(rawNote & 0x0F, 0, 11);
if (channel.pitchBend >= 0) {
table = _pitchBendTables[baseNote + 2];
table = _pitchBendTables[indexNote + 2];
freq += table[CLIP(+channel.pitchBend, 0, 31)];
} else {
table = _pitchBendTables[baseNote];
table = _pitchBendTables[indexNote];
freq -= table[CLIP(-channel.pitchBend, 0, 31)];
}
}
// Shift octave to correct bit position and limit to valid range.
octave = CLIP<int8>(octave, 0, 7) << 2;
// Update octave & frequency, but keep on/off state.
channel.regAx = freq & 0xFF;
channel.regBx = (channel.regBx & 0x20) | (octave << 2) | ((freq >> 8) & 0x03);
channel.regBx = (channel.regBx & 0x20) | octave | ((freq >> 8) & 0x03);
// Keep the note on or off
writeOPL(0xA0 + _curChannel, channel.regAx);
writeOPL(0xB0 + _curChannel, channel.regBx);
}