WaveTrackCache was only used with float; don't support other formats

src/Mix.cpp

@@ -460,7 +460,8 @@ size_t Mixer::MixVariableRates(int *channelFlags, WaveTrackCache &cache,
          // Nothing to do if past end of play interval
          if (getLen > 0) {
             if (backwards) {
-               auto results = cache.Get(floatSample, *pos - (getLen - 1), getLen, mMayThrow);
+               auto results =
+                  cache.GetFloats(*pos - (getLen - 1), getLen, mMayThrow);
                if (results)
                   memcpy(&queue[*queueLen], results, sizeof(float) * getLen);
                else
@@ -472,7 +473,7 @@ size_t Mixer::MixVariableRates(int *channelFlags, WaveTrackCache &cache,
                *pos -= getLen;
             }
             else {
-               auto results = cache.Get(floatSample, *pos, getLen, mMayThrow);
+               auto results = cache.GetFloats(*pos, getLen, mMayThrow);
                if (results)
                   memcpy(&queue[*queueLen], results, sizeof(float) * getLen);
                else
@@ -589,7 +590,7 @@ size_t Mixer::MixSameRate(int *channelFlags, WaveTrackCache &cache,
    );
 
    if (backwards) {
-      auto results = cache.Get(floatSample, *pos - (slen - 1), slen, mMayThrow);
+      auto results = cache.GetFloats(*pos - (slen - 1), slen, mMayThrow);
       if (results)
          memcpy(mFloatBuffer.get(), results, sizeof(float) * slen);
       else
@@ -602,7 +603,7 @@ size_t Mixer::MixSameRate(int *channelFlags, WaveTrackCache &cache,
       *pos -= slen;
    }
    else {
-      auto results = cache.Get(floatSample, *pos, slen, mMayThrow);
+      auto results = cache.GetFloats(*pos, slen, mMayThrow);
       if (results)
          memcpy(mFloatBuffer.get(), results, sizeof(float) * slen);
       else

src/WaveClip.cpp

@@ -707,8 +707,8 @@ bool SpecCache::CalculateOneSpectrum
          }
 
          if (myLen > 0) {
-            useBuffer = (float*)(waveTrackCache.Get(
+            useBuffer = (float*)(waveTrackCache.GetFloats(
-               floatSample, sampleCount(
+               sampleCount(
                   floor(0.5 + from.as_double() + offset * rate)
                ),
                myLen,

src/WaveTrack.cpp

@@ -2542,9 +2542,10 @@ void WaveTrackCache::SetTrack(const std::shared_ptr<const WaveTrack> &pTrack)
    }
 }
 
-constSamplePtr WaveTrackCache::Get(sampleFormat format,
+const float *WaveTrackCache::GetFloats(
    sampleCount start, size_t len, bool mayThrow)
 {
+   constexpr auto format = floatSample;
    if (format == floatSample && len > 0) {
       const auto end = start + len;
 
@@ -2596,7 +2597,7 @@ constSamplePtr WaveTrackCache::Get(sampleFormat format,
             if (!mPTrack->Get(
                   samplePtr(mBuffers[0].data.get()), floatSample, start0, len0,
                   fillZero, mayThrow))
-               return 0;
+               return nullptr;
             mBuffers[0].start = start0;
             mBuffers[0].len = len0;
             if (!fillSecond &&
@@ -2622,7 +2623,7 @@ constSamplePtr WaveTrackCache::Get(sampleFormat format,
                const auto len1 = mPTrack->GetBestBlockSize(start1);
                wxASSERT(len1 <= mBufferSize);
                if (!mPTrack->Get(samplePtr(mBuffers[1].data.get()), floatSample, start1, len1, fillZero, mayThrow))
-                  return 0;
+                  return nullptr;
                mBuffers[1].start = start1;
                mBuffers[1].len = len1;
                mNValidBuffers = 2;
@@ -2648,7 +2649,7 @@ constSamplePtr WaveTrackCache::Get(sampleFormat format,
          auto sinitLen = initLen.as_size_t();
          if (!mPTrack->Get(mOverlapBuffer.ptr(), format, start, sinitLen,
                            fillZero, mayThrow))
-            return 0;
+            return nullptr;
          wxASSERT( sinitLen <= remaining );
          remaining -= sinitLen;
          start += initLen;
@@ -2669,7 +2670,7 @@ constSamplePtr WaveTrackCache::Get(sampleFormat format,
             // All is contiguous already.  We can completely avoid copying
             // leni is nonnegative, therefore start falls within mBuffers[ii],
             // so starti is bounded between 0 and buffer length
-            return samplePtr(mBuffers[ii].data.get() + starti.as_size_t() );
+            return mBuffers[ii].data.get() + starti.as_size_t() ;
          }
          else if (leni > 0) {
             // leni is nonnegative, therefore start falls within mBuffers[ii]
@@ -2700,15 +2701,21 @@ constSamplePtr WaveTrackCache::Get(sampleFormat format,
             return 0;
       }
 
-      return mOverlapBuffer.ptr();
+      // Overlap buffer was meant for the more general support of sample formats
+      // besides float, which explains the cast
+      return reinterpret_cast<const float*>(mOverlapBuffer.ptr());
+   }
+   else {
+#if 0
+      // Cache works only for float format.
+      mOverlapBuffer.Resize(len, format);
+      if (mPTrack->Get(mOverlapBuffer.ptr(), format, start, len, fillZero, mayThrow))
+         return mOverlapBuffer.ptr();
+#else
+      // No longer handling other than float format.  Therefore len is 0.
+#endif
+      return nullptr;
    }
-
-   // Cache works only for float format.
-   mOverlapBuffer.Resize(len, format);
-   if (mPTrack->Get(mOverlapBuffer.ptr(), format, start, len, fillZero, mayThrow))
-      return mOverlapBuffer.ptr();
-   else
-      return 0;
 }
 
 void WaveTrackCache::Free()

src/WaveTrack.h

@@ -592,10 +592,9 @@ private:
    std::unique_ptr<WaveformSettings> mpWaveformSettings;
 };
 
-// This is meant to be a short-lived object, during whose lifetime,
+//! A short-lived object, during whose lifetime, the contents of the WaveTrack are assumed not to change.
-// the contents of the WaveTrack are known not to change.  It can replace
+/*! It can replace repeated calls to WaveTrack::Get() (each of which opens and closes at least one block).
-// repeated calls to WaveTrack::Get() (each of which opens and closes at least
+ */
-// one block file).
 class AUDACITY_DLL_API WaveTrackCache {
 public:
    WaveTrackCache()
@@ -617,12 +616,11 @@ public:
    const std::shared_ptr<const WaveTrack>& GetTrack() const { return mPTrack; }
    void SetTrack(const std::shared_ptr<const WaveTrack> &pTrack);
 
-   // Uses fillZero always
+   //! Retrieve samples as floats from the track or from the memory cache
-   // Returns null on failure
+   /*! Uses fillZero always
-   // Returned pointer may be invalidated if Get is called again
+    @return null on failure; this object owns the memory; may be invalidated if GetFloats() is called again
-   // Do not DELETE[] the pointer
+   */
-   constSamplePtr Get(
+   const float *GetFloats(sampleCount start, size_t len, bool mayThrow);
-      sampleFormat format, sampleCount start, size_t len, bool mayThrow);
 
 private:
    void Free();