Method fromOccupancyGrid

grid_map_ros/src/GridMapRosConverter.cpp:225–269

}

bool GridMapRosConverter::fromOccupancyGrid(const nav_msgs::OccupancyGrid& occupancyGrid,
                                            const std::string& layer, grid_map::GridMap& gridMap)
{
  const Size size(occupancyGrid.info.width, occupancyGrid.info.height);
  const double resolution = occupancyGrid.info.resolution;
  const Length length = resolution * size.cast<double>();
  const string& frameId = occupancyGrid.header.frame_id;
  Position position(occupancyGrid.info.origin.position.x, occupancyGrid.info.origin.position.y);
  // Different conventions of center of map.
  position += 0.5 * length.matrix();

  const auto& orientation = occupancyGrid.info.origin.orientation;
  if (orientation.w != 1.0 && !(orientation.x == 0 && orientation.y == 0
      && orientation.z == 0 && orientation.w == 0)) {
    ROS_WARN_STREAM("Conversion of occupancy grid: Grid maps do not support orientation.");
    ROS_INFO_STREAM("Orientation of occupancy grid: " << endl << occupancyGrid.info.origin.orientation);
    return false;
  }

  if (size.prod() != occupancyGrid.data.size()) {
    ROS_WARN_STREAM("Conversion of occupancy grid: Size of data does not correspond to width * height.");
    return false;
  }

  // TODO: Split to `initializeFrom` and `from` as for Costmap2d.
  if ((gridMap.getSize() != size).any() || gridMap.getResolution() != resolution
      || (gridMap.getLength() != length).any() || gridMap.getPosition() != position
      || gridMap.getFrameId() != frameId || !gridMap.getStartIndex().isZero()) {
    gridMap.setTimestamp(occupancyGrid.header.stamp.toNSec());
    gridMap.setFrameId(frameId);
    gridMap.setGeometry(length, resolution, position);
  }

  // Reverse iteration is required because of different conventions
  // between occupancy grid and grid map.
  grid_map::Matrix data(size(0), size(1));
  for (std::vector<int8_t>::const_reverse_iterator iterator = occupancyGrid.data.rbegin();
      iterator != occupancyGrid.data.rend(); ++iterator) {
    size_t i = std::distance(occupancyGrid.data.rbegin(), iterator);
    data(i) = *iterator != -1 ? *iterator : NAN;
  }

  gridMap.add(layer, data);
  return true;
}

void GridMapRosConverter::toOccupancyGrid(const grid_map::GridMap& gridMap,
                                          const std::string& layer, float dataMin, float dataMax,