diff options
| -rw-r--r-- | backends/midi/emumidi.h | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/backends/midi/emumidi.h b/backends/midi/emumidi.h index 787d8912f7..529662b7ee 100644 --- a/backends/midi/emumidi.h +++ b/backends/midi/emumidi.h @@ -54,7 +54,14 @@ public: int open() { _isOpen = true; - _samples_per_tick = (getRate() << FIXP_SHIFT) / BASE_FREQ; + + int d = getRate() / BASE_FREQ; + int r = getRate() % BASE_FREQ; + + // This is equivalent to (getRate() << FIXP_SHIFT) / BASE_FREQ + // but less prone to arithmetic overflow. + + _samples_per_tick = (d << FIXP_SHIFT) + (r << FIXP_SHIFT) / BASE_FREQ; return 0; } @@ -71,11 +78,12 @@ public: const int stereoFactor = isStereo() ? 2 : 1; int len = numSamples / stereoFactor; int step; - + do { step = len; if (step > (_next_tick >> FIXP_SHIFT)) step = (_next_tick >> FIXP_SHIFT); + generate_samples(data, step); _next_tick -= step << FIXP_SHIFT; |