Return a sample pointer from resamplers

Both resampling and filtering now avoid copying samples when they no-op.

3 files changed, 21 insertions, 19 deletions

diff --git a/Alc/mixer.c b/Alc/mixer.c
index 86a0eef6..6ee76d1f 100644
--- a/Alc/mixer.c
+++ b/Alc/mixer.c
@@ -176,8 +176,8 @@ ALvoid MixSource(ALactivesource *src, ALCdevice *Device, ALuint SamplesToDo)
 
         for(chan = 0;chan < NumChannels;chan++)
         {
-            ALfloat *SrcData = Device->SampleData1;
-            ALfloat *ResampledData = Device->SampleData2;
+            const ALfloat *ResampledData;
+            ALfloat *SrcData = Device->SourceData;
             ALuint SrcDataSize = 0;
 
             if(Source->SourceType == AL_STATIC)
@@ -341,16 +341,18 @@ ALvoid MixSource(ALactivesource *src, ALCdevice *Device, ALuint SamplesToDo)
             }
 
             /* Now resample, then filter and mix to the appropriate outputs. */
-            src->Resample(&SrcData[BufferPrePadding], DataPosFrac,
-                          increment, ResampledData, DstBufferSize);
-
+            ResampledData = src->Resample(
+                &SrcData[BufferPrePadding], DataPosFrac, increment,
+                Device->ResampledData, DstBufferSize
+            );
             {
                 DirectParams *parms = &src->Direct;
                 const ALfloat *samples;
 
                 samples = DoFilters(
                     &parms->Filters[chan].LowPass, &parms->Filters[chan].HighPass,
-                    SrcData, ResampledData, DstBufferSize, parms->Filters[chan].ActiveType
+                    Device->FilteredData, ResampledData, DstBufferSize,
+                    parms->Filters[chan].ActiveType
                 );
                 if(!src->IsHrtf)
                     src->Dry.Mix(parms->OutBuffer, samples, &parms->Mix.Gains[chan],
@@ -375,7 +377,8 @@ ALvoid MixSource(ALactivesource *src, ALCdevice *Device, ALuint SamplesToDo)
 
                 samples = DoFilters(
                     &parms->Filters[chan].LowPass, &parms->Filters[chan].HighPass,
-                    SrcData, ResampledData, DstBufferSize, parms->Filters[chan].ActiveType
+                    Device->FilteredData, ResampledData, DstBufferSize,
+                    parms->Filters[chan].ActiveType
                 );
                 src->WetMix(parms->OutBuffer, samples, &parms->Gain,
                             maxu(parms->Counter, OutPos) - OutPos,
diff --git a/Alc/mixer_c.c b/Alc/mixer_c.c
index 4cc76a0f..389971e0 100644
--- a/Alc/mixer_c.c
+++ b/Alc/mixer_c.c
@@ -15,28 +15,27 @@ static inline ALfloat lerp32(const ALfloat *vals, ALuint frac)
 static inline ALfloat cubic32(const ALfloat *vals, ALuint frac)
 { return cubic(vals[-1], vals[0], vals[1], vals[2], frac * (1.0f/FRACTIONONE)); }
 
-void Resample_copy32_C(const ALfloat *data, ALuint UNUSED(frac),
-  ALuint increment, ALfloat *restrict OutBuffer, ALuint BufferSize)
+const ALfloat *Resample_copy32_C(const ALfloat *data, ALuint UNUSED(frac),
+  ALuint increment, ALfloat *restrict UNUSED(OutBuffer), ALuint UNUSED(BufferSize))
 {
     assert(increment==FRACTIONONE);
-    memcpy(OutBuffer, data, BufferSize*sizeof(ALfloat));
+    return data;
 }
 
 #define DECL_TEMPLATE(Sampler)                                                \
-void Resample_##Sampler##_C(const ALfloat *data, ALuint frac,                 \
+const ALfloat *Resample_##Sampler##_C(const ALfloat *data, ALuint frac,       \
   ALuint increment, ALfloat *restrict OutBuffer, ALuint BufferSize)           \
 {                                                                             \
-    ALuint pos = 0;                                                           \
     ALuint i;                                                                 \
-                                                                              \
     for(i = 0;i < BufferSize;i++)                                             \
     {                                                                         \
-        OutBuffer[i] = Sampler(data + pos, frac);                             \
+        OutBuffer[i] = Sampler(data, frac);                                   \
                                                                               \
         frac += increment;                                                    \
-        pos  += frac>>FRACTIONBITS;                                           \
+        data += frac>>FRACTIONBITS;                                           \
         frac &= FRACTIONMASK;                                                 \
     }                                                                         \
+    return OutBuffer;                                                         \
 }
 
 DECL_TEMPLATE(point32)
diff --git a/Alc/mixer_defs.h b/Alc/mixer_defs.h
index 130743c5..04fd1f53 100644
--- a/Alc/mixer_defs.h
+++ b/Alc/mixer_defs.h
@@ -12,10 +12,10 @@ struct HrtfParams;
 struct HrtfState;
 
 /* C resamplers */
-void Resample_copy32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
-void Resample_point32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
-void Resample_lerp32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
-void Resample_cubic32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
+const ALfloat *Resample_copy32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
+const ALfloat *Resample_point32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
+const ALfloat *Resample_lerp32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
+const ALfloat *Resample_cubic32_C(const ALfloat *src, ALuint frac, ALuint increment, ALfloat *restrict dst, ALuint dstlen);
 
 
 /* C mixers */