WDL scratch buffers

static constexpr int kNumModSources = 10;

class MySynth
{
public:
  MySynth()
  {
    SetScratchBuffers(DEFAULT_BLOCK_SIZE);
  }
  
  // call in OnReset()
  void SetScratchBuffers(int blockSize)
  {
    // could check and only resize if blockSize > current blocksize
    mModScratch.Resize(blockSize * kNumModSources); // resize scratch buffers
    memset(mModScratch.Get(), 0, blockSize * kNumModSources * sizeof(float)); zero the memory
  
    mModulations.Empty(); // empty the ptr list
  
    for(auto i = 0; i < kNumModSources; i++)
    {
      mModulations.Add(mModScratch.Get() + (i * blockSize)); // update the ptrs
    }
  }
  
  void ProcessBlock(int nFrames)
  {
    float** moduation = mModulations.GetList();
    
    float* mod1 = modulation[0];
    
    for(int i=0i<nFrames;i++)
    {
      *mod1 = runMyLFO(); // update per sample
      
      mod1++;
    }
  }
  
private:
  WDL_TypedBuf<float> mModScratch;
  WDL_PtrList<float> mModulations;
};