GB Audio: Channel 4 fixes (fixes #1265, closes #1289)

This commit is contained in:
Vicki Pfau 2019-09-14 13:08:34 -07:00
parent df5b6b7351
commit 1dc405db38
2 changed files with 9 additions and 7 deletions

View File

@ -40,6 +40,8 @@ Emulation fixes:
- GB Memory: Better emulate 0xFEA0 region on DMG, MGB and AGB
- GB Printer: Reset printer buffer index after printing
- GB Video: Fix mode 0 window edge case (fixes mgba.io/i/1519)
- GBA Audio: Fix channel 4 aliasing (fixes mgba.io/i/1265)
- GB Audio: Improve channel 4 supersampling
Other fixes:
- Qt: Fix some Qt display driver race conditions
- Core: Improved lockstep driver reliability (Le Hoang Quyen)

View File

@ -37,7 +37,7 @@ static bool _updateSweep(struct GBAudioSquareChannel* sweep, bool initial);
static void _updateSquareSample(struct GBAudioSquareChannel* ch);
static int32_t _updateSquareChannel(struct GBAudioSquareChannel* ch);
static int8_t _coalesceNoiseChannel(struct GBAudioNoiseChannel* ch);
static int16_t _coalesceNoiseChannel(struct GBAudioNoiseChannel* ch);
static void _updateFrame(struct mTiming* timing, void* user, uint32_t cyclesLate);
static void _updateChannel1(struct mTiming* timing, void* user, uint32_t cyclesLate);
@ -632,8 +632,11 @@ void GBAudioSamplePSG(struct GBAudio* audio, int16_t* left, int16_t* right) {
}
}
sampleLeft <<= 3;
sampleRight <<= 3;
if (!audio->forceDisableCh[3]) {
int8_t sample = _coalesceNoiseChannel(&audio->ch4);
int16_t sample = audio->style == GB_AUDIO_GBA ? (audio->ch4.sample << 3) : _coalesceNoiseChannel(&audio->ch4);
if (audio->ch4Left) {
sampleLeft += sample;
}
@ -643,9 +646,6 @@ void GBAudioSamplePSG(struct GBAudio* audio, int16_t* left, int16_t* right) {
}
}
sampleLeft <<= 3;
sampleRight <<= 3;
*left = sampleLeft * (1 + audio->volumeLeft);
*right = sampleRight * (1 + audio->volumeRight);
}
@ -768,12 +768,12 @@ static int32_t _updateSquareChannel(struct GBAudioSquareChannel* ch) {
}
}
static int8_t _coalesceNoiseChannel(struct GBAudioNoiseChannel* ch) {
static int16_t _coalesceNoiseChannel(struct GBAudioNoiseChannel* ch) {
if (!ch->nSamples) {
return ch->sample;
}
// TODO keep track of timing
int8_t sample = ch->samples / ch->nSamples;
int16_t sample = (ch->samples << 3) / ch->nSamples;
ch->nSamples = 0;
ch->samples = 0;
return sample;