citygml-tools

citygml-tools is a command line utility that bundles several operations for processing CityGML files.

License

citygml-tools is licensed under the Apache License, Version 2.0. See the LICENSE file for more details.

Latest release

The latest stable release of citygml-tools is 2.3.2.

Download the latest citygml-tools release as ZIP package here. Previous releases are available from the releases section.

Contributing

To file bugs found in the software create a GitHub issue.
To contribute code for fixing filed issues create a pull request with the issue id.
To propose a new feature create a GitHub issue and open a discussion.

Using citygml-tools

Download and unzip the latest release or build the program from source. Afterwards, open a shell environment and run the citygml-tools script from the program folder to launch the program.

To show the help message and all available commands of citygml-tools, simply type the following:

> citygml-tools --help

This will print the following usage information:

Usage: citygml-tools [-hV] [--extensions=<folder>] [-L=<level>]
                     [--log-file=<file>] [--pid-file=<file>] [@<filename>...]
                     [COMMAND]
Collection of tools for processing CityGML files.
      [@<filename>...]      One or more argument files containing options.
  -L, --log-level=<level>   Log level: error, warn, info, debug (default: info).
      --log-file=<file>     Write log messages to this file.
      --pid-file=<file>     Create a file containing the process ID.
      --extensions=<folder> Load extensions from this folder.
  -h, --help                Show this help message and exit.
  -V, --version             Print version information and exit.
Commands:
  help           Displays help information about the specified command
  stats          Generates statistics about the content of CityGML files.
  validate       Validates CityGML files against the CityGML XML schemas.
  apply-xslt     Transforms city objects based on XSLT stylesheets.
  change-height  Changes the height values of city objects by a given offset.
  remove-apps    Removes appearances from city objects.
  to-local-apps  Converts global appearances into local ones.
  clip-textures  Clips texture images to the extent of the target surface.
  subset         Creates a subset of city objects based on filter criteria.
  filter-lods    Filters LoD representations of city objects.
  reproject      Reprojects city objects to a new coordinate reference system.
  from-cityjson  Converts CityJSON files into CityGML.
  to-cityjson    Converts CityGML files into CityJSON.
  upgrade        Upgrades CityGML files to version 3.0.

To get help about a specific command of citygml-tools, enter the following and replace COMMAND with the name of the command you want to learn more about:

> citygml-tools help COMMAND

The following example shows how to use the stats command to generate and print statistics about the content of the specified CityGML file:

> citygml-tools stats /path/to/your/CityGML.gml

Supported CityGML versions

You can process CityGML 3.0, 2.0, and 1.0 files with citygml-tools. The upgrade command provides an easy way to convert your existing CityGML 2.0 and 1.0 datasets into the latest version 3.0 of CityGML.

The from-cityjson and to-cityjson commands support CityJSON 2.0, 1.1, and 1.0 files.

System requirements

Java 17 or higher

citygml-tools can be run on any platform providing appropriate Java support.

Docker

citygml-tools is also available as Docker image. You can either build the image yourself using the provided Dockerfile or use a pre-built image from Docker Hub or GitHub packages. The pre-built images support the most common architectures (amd64, arm64).

To build the image, clone the repository to your local machine and run the following command from the root of the repository:

> docker build -t citygml-tools .

An official image can be pulled from Docker Hub as shown below.

> docker pull citygml4j/citygml-tools:TAG

Replace the TAG label with the version of citygml-tools you want to use such as v2.3.2. The latest tag refers to the latest stable release and is also the default value if no tag is specified. If you want to pull the most recent unreleased snapshot of citygml-tools, use edge as tag.

How to use the image

Using citygml-tools via Docker is simple:

 > docker run --rm citygml-tools

This will show the help message and all available commands of citygml-tools.

The following command mounts a local directory at /data using the -v parameter and runs the to-cityjson command of citygml-tools to convert all CityGML files in the mounted volume into CityJSON.

> docker run --rm -u 1000 -v /path/to/your/data:/data citygml-tools to-cityjson *.gml

Note that /data is the default working directory inside the container. Relative paths to input files like in the above example are automatically resolved against /data by citygml-tools. If you mount your local directory at a different path inside the container, you must specify the full path to your input files, of course.

Use the -u parameter to pass the username or UID of your current host's user to set the correct file permissions on generated files in the mounted directory.

Technical details

The citygml-tools image uses Eclipse Temurin OpenJDK binaries for Alpine Linux to keep the resulting images small. Additionally, it is written as multi-stage image, which means the "JDK image" is only used for building, while the final application gets wrapped in a smaller "JRE image".

By default, the container process is executed as non-root user. The default working directory inside the container is /data.

Building

citygml-tools uses Gradle as build system. To build the program from source, clone the repository to your local machine and run the following command from the root of the repository.

> gradlew installDist

The script automatically downloads all required dependencies for building and running citygml-tools. So make sure you are connected to the internet.

If the build was successful, you will find the citygml-tools package under citygml-tools/build/install.