diff options
| author | Chris Robinson <chris.kcat@gmail.com> | 2018-12-01 13:47:56 -0800 |
|---|---|---|
| committer | Chris Robinson <chris.kcat@gmail.com> | 2018-12-01 13:47:56 -0800 |
| commit | e1af866a3df96b5af3173c5ce85ebba25841dc4d (patch) | |
| tree | f1bea7c412461a9f68811d970900082bbedafeb9 /Alc/mixvoice.cpp | |
| parent | 255c07def9814b1c07196983a0a670dccccc0d50 (diff) | |
Rework source sample counting for mixing a bit
Diffstat (limited to 'Alc/mixvoice.cpp')
| -rw-r--r-- | Alc/mixvoice.cpp | 46 |
1 files changed, 27 insertions, 19 deletions
diff --git a/Alc/mixvoice.cpp b/Alc/mixvoice.cpp index f0ee8bb6..b873a744 100644 --- a/Alc/mixvoice.cpp +++ b/Alc/mixvoice.cpp @@ -331,25 +331,33 @@ ALboolean MixSource(ALvoice *voice, ALuint SourceID, ALCcontext *Context, ALsize do { /* Figure out how many buffer samples will be needed */ - ALint64 DataSize64{SamplesToDo - OutPos}; - DataSize64 *= increment; - DataSize64 += DataPosFrac+FRACTIONMASK; - DataSize64 >>= FRACTIONBITS; - DataSize64 += MAX_RESAMPLE_PADDING*2; - ALsizei SrcBufferSize{(ALsizei)mini64(DataSize64, BUFFERSIZE)}; - - /* Figure out how many samples we can actually mix from this. */ - DataSize64 = SrcBufferSize; - DataSize64 -= MAX_RESAMPLE_PADDING*2; - DataSize64 <<= FRACTIONBITS; - DataSize64 -= DataPosFrac; - ALsizei DstBufferSize{(ALsizei)mini64((DataSize64+(increment-1)) / increment, - SamplesToDo - OutPos)}; - - /* Some mixers like having a multiple of 4, so try to give that unless - * this is the last update. */ - if(DstBufferSize < SamplesToDo-OutPos) - DstBufferSize &= ~3; + ALsizei DstBufferSize{SamplesToDo - OutPos}; + + /* Calculate the last written dst sample pos. */ + ALint64 DataSize64{DstBufferSize - 1}; + /* Calculate the last read src sample pos. */ + DataSize64 = (DataSize64*increment + DataPosFrac) >> FRACTIONBITS; + /* +1 to get the src sample count, include padding. */ + DataSize64 += 1 + MAX_RESAMPLE_PADDING*2; + + auto SrcBufferSize = static_cast<ALsizei>(mini64(DataSize64, BUFFERSIZE+1)); + if(SrcBufferSize > BUFFERSIZE) + { + SrcBufferSize = BUFFERSIZE; + /* If the source buffer got saturated, we can't fill the desired + * dst size. Figure out how many samples we can actually mix from + * this. + */ + DataSize64 = SrcBufferSize - MAX_RESAMPLE_PADDING*2; + DataSize64 = ((DataSize64<<FRACTIONBITS) - DataPosFrac + increment-1) / increment; + DstBufferSize = static_cast<ALsizei>(mini64(DataSize64, DstBufferSize)); + + /* Some mixers like having a multiple of 4, so try to give that + * unless this is the last update. + */ + if(DstBufferSize < SamplesToDo-OutPos) + DstBufferSize &= ~3; + } /* It's impossible to have a buffer list item with no entries. */ assert(BufferListItem->num_buffers > 0); |