Function encodeDraco

pj_scene3D/tests/pointcloud_codecs_test.cpp:73–95

Draco-encode POSITION (x,y,z) + one GENERIC (intensity) attribute, sequential (lossless float) so positions round-trip closely. When generic_meta_name is given, the GENERIC attribute is tagged with that name in Draco attribute metadata (the Foxglove / draco_point_cloud_transport convention).

// the GENERIC attribute is tagged with that name in Draco attribute metadata (the
// Foxglove / draco_point_cloud_transport convention).
std::vector<uint8_t> encodeDraco(const std::vector<Pt>& pts, const char* generic_meta_name = nullptr) {
  draco::PointCloudBuilder builder;
  builder.Start(static_cast<draco::PointIndex::ValueType>(pts.size()));
  const int pos_att = builder.AddAttribute(draco::GeometryAttribute::POSITION, 3, draco::DT_FLOAT32);
  const int gen_att = builder.AddAttribute(draco::GeometryAttribute::GENERIC, 1, draco::DT_FLOAT32);
  for (size_t i = 0; i < pts.size(); ++i) {
    const float xyz[3] = {pts[i].x, pts[i].y, pts[i].z};
    builder.SetAttributeValueForPoint(pos_att, draco::PointIndex(static_cast<uint32_t>(i)), xyz);
    builder.SetAttributeValueForPoint(gen_att, draco::PointIndex(static_cast<uint32_t>(i)), &pts[i].intensity);
  }
  if (generic_meta_name != nullptr) {
    auto meta = std::make_unique<draco::AttributeMetadata>();
    meta->AddEntryString("name", generic_meta_name);
    builder.AddAttributeMetadata(gen_att, std::move(meta));
  }
  std::unique_ptr<draco::PointCloud> pc = builder.Finalize(/*deduplicate_points=*/false);
  draco::Encoder encoder;
  encoder.SetEncodingMethod(draco::POINT_CLOUD_SEQUENTIAL_ENCODING);
  draco::EncoderBuffer buffer;
  const draco::Status status = encoder.EncodePointCloudToBuffer(*pc, &buffer);
  EXPECT_TRUE(status.ok()) << status.error_msg();
  return std::vector<uint8_t>(buffer.data(), buffer.data() + buffer.size());
}

CompressedPointCloud wrap(std::vector<uint8_t> blob, std::string format, std::string frame_id, int64_t ts_ns) {
  auto owned = std::make_shared<std::vector<uint8_t>>(std::move(blob));