message: gltfpack: Implement inverseBindMatrix transforms
  In theory this should work, but in practice something doesn't quite work
  right...
diff: @@ -1091,7 +1091,18 @@ bool process(Scene& scene, const Settings& settings, std::string& json, std::str
  cgltf_accessor_read_float(skin.inverse_bind_matrices, j, transform, 16);
  }
  - // TODO: transform qp
  + // TODO: this is what should happen, right?
  + if (0)
  + {
  + float node_scale = qp.pos_scale / float((1 << qp.pos_bits) - 1);
  +
  + for (int k = 0; k < 12; ++k)
  + transform[k] *= node_scale;
  +
  + transform[12] += qp.pos_offset[0];
  + transform[13] += qp.pos_offset[1];
  + transform[14] += qp.pos_offset[2];
  + }
  bin.append(reinterpret_cast<const char*>(transform), sizeof(transform));
  }
  