roofer

Automatic 3D building reconstruction

Overview src/ folder (possibly subject to change)

src/common.hpp and src/Raster.hpp contains some basic types to store pointclouds, polygons, rasters etc that are used throughout the library. Only depends on the C++17 standard library.

src/detection and src/partitioning contain everything needed to perform building reconstruction (see apps/reconstruct.cpp for how to use). These files only depend on CGAL, there are not other external dependencies.

src/io contains functions to read and write OGR/GDAL datasources and LAS files. Has a bunch of external dependencies like GDAL, GEOS, PROJ, LASlib

src/misc, src/quality various function used by the crop application.

Roofer apps

crop

Takes a bunch of input las files and footprints and outputs a folder hierarchy with reconstruction inputs for each separate building

reconstruct

Takes a point cloud and footprint for a single building and performs building reconstruction.

Currently it is using rerun.io to visualise the result. You need to install the rerun viewer if you want to see the output.

roofer

Combines crop and reconstruct and serialization.

By default, roofer uses all concurrent threads that are supported by the machine. You can limit the total number of threads used by roofer with the -j, --jobs parameter. However, roofer requires at least 6 concurrent threads, so that is the minimum that will be used, even if -j is set to a lower value.

Performance

On Linux, we strongly recommend to run roofer with the jemalloc memory allocator instead of the default glibc. After installing jemalloc, you can enable it by setting LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libjemalloc.so.2.

Compile from source

Building roofer requires vcpkg. Follow the vcpkg instructions to set it up. After vcpkg is set up, set the VCPKG_ROOT environment variable to point to the directory where vcpkg is installed.

On macOS you need to install additional build tools:

brew install autoconf autoconf-archive automake libtool

export PATH="/opt/homebrew/opt/m4/bin:$PATH"

Clone this repository and use one of the CMake presets to build the roofer.

cd geoflow-roofer
mkdir build
cmake --preset vcpkg-minimal -S . -B build
cmake --build build
# Optionally, install roofer
cmake --install build

You can list all available presets:

cd geoflow-roofer
cmake --list-presets

If you are using a preset, you can still enable individual dependencies, e.g. spdlog:

cmake --preset vcpkg-minimal -DRF_USE_LOGGER_SPDLOG=ON -S . -B build

Logging

There are two logging backends available, the internal and spdlog. Roofer defaults to the internal logger, which logs to the console. With spdlog, roofer logs to the console and to a JSON log file. To use spdlog, set the RF_USE_LOGGER_SPDLOG CMake variable ON.

The logging verbosity is controlled with the -v, --verbose and -t, --trace options.

Tracing

The roofer app can trace object counts and the amount of heap allocation during its process. To enable tracing, pass the --trace option to roofer. It is strongly recommended to use spdlog if you enable tracing, so that the logs are stored as JSON in the roofer.log.json logfile. The tools/plot_traces.py python script can help you to plot the tracing information. The script requires the matplotlib and pandas libraries to run, it takes the log file as its single argument and writes the plot to roofer_trace_plot.png.