Ticket #8131: mixer.diff

scummvm/sound/mixer.cpp

@@ -837 +837 @@
 
                 while ((_posInFrame < _synth.pcm.length) && (len > 0)) {
                         int16 sample = (int16)((scale_sample(*ch) * volume) / 32);
-                        *data++ += sample;
-                        *data++ += sample;
+                        *data = clamped_add_16(*data, sample);
+                        data++;
+                        *data = clamped_add_16(*data, sample);
+                        data++;
                         len--;
                         ch++;
                         _posInFrame++;
@@ -957 +959 @@
                 ch = _synth.pcm.samples[0] + _posInFrame;
                 while ((_posInFrame < _synth.pcm.length) && (len > 0)) {
                         int16 sample = (int16)((scale_sample(*ch++) * volume) / 32);
-                        *data++ += sample;
-                        *data++ += sample;
+                        *data = clamped_add_16(*data, sample);
+                        data++;
+                        *data = clamped_add_16(*data, sample);
+                        data++;
                         len--;
                         _posInFrame++;
                 }
@@ -1083 +1087 @@
         // Mix the samples in
         for (uint i = 0; i < len; i++) {
                 int16 sample = (int16) ((int32) samples[i * channels] * volume / 256);
-                *data++ += sample;
+                *data = clamped_add_16(*data, sample);
+                data++;
                 if (channels > 1)
                         sample = (int16) ((int32) samples[i * channels + 1] * volume / 256);
-                *data++ += sample;
+                *data = clamped_add_16(*data, sample);
+                data++;
         }
 
         delete [] samples;