message: cleanup particles at block deallocation
diff: @@ -98,6 +98,10 @@ void PfxBucket::freeBlock(size_t& i) {
  return;
  auto& b = block[i];
  assert(b.count==0);
  +
  + Vertex* v = &vboCpu[b.offset*vertexCount];
  + std::memset(v,0,blockSize*vertexCount*sizeof(*v));
  +
  b.allocated = false;
  i = size_t(-1);
  }
  