Shared export options

Both CityGML and CityJSON exporters in the 3DCityDB Tool share a common set of options. These options allow users to customize the export process, including output configuration, query and filter parameters, and tiling for large datasets.

General Options¶

Option	Description	Default Value
`-o`, `--output=<file>`	Name of the output file.
`--output-encoding=<encoding>`	Specify the encoding for the output file.
`--fail-fast`	Stop execution immediately upon encountering an error.
`--temp-dir=<dir>`	Directory for storing temporary files.
`--threads=<threads>`	Number of threads for parallel processing.
`--crs=<crs>`	SRID or CRS identifier for geometry coordinates.	storage CRS
`--crs-name=<name>`	Name of the CRS to include in the output.
`--no-appearances`	Exclude appearances from the export.
`--pretty-print`	Format and indent the output file (default: true).	true
`--config-file=<file>`	Load configuration options from the specified file.
`-L`, `--log-level=<level>`	Set the logging level: fatal, error, warn, info, debug, trace.	info
`--log-file=<file>`	Write log messages to the specified file.
`--pid-file=<file>`	Create a process ID file.
`--plugins=<dir>`	Load plugins from the specified directory.
`--use-plugins=<plugin>`	Enable/disable plugins using their fully qualified names.	true

Option	Description	Default Value
`-t`, `--type-name=<name>`	Specify feature names to process. Example: `CityFurniture`.	None
`-f`, `--filter=<cql2-text>`	Apply a CQL2 filter to retrieve specific features.	None
`--filter-crs=<crs>`	SRID or CRS identifier for the filter geometries.	Storage CRS
`--sql-filter=<sql>`	Use an SQL query expression to filter features.	None
`-s`, `--sort-by=<property>`	Sort features by the specified property. Example: `height`.	None
`--limit=<count>`	Limit the number of features processed. Example: `5`.	No limit
`--start-index=<index>`	Start processing features from the specified index.	`0`
`-l`, `--lod=<lod>`	Export geometries with a matching Level of Detail (LoD).	None
`--lod-mode=<mode>`	LoD filter mode: `or`, `and`, `minimum`, `maximum`.	`or`
`--lod-search-depth=<depth>`	Levels of sub-features to search for matching LoDs.	`0`
`-a`, `--appearance-theme=<theme>`	Export appearances with a matching theme. Use `none` for null themes.	None

Tiling Options¶

Tiling options allow users to divide the output data into smaller tiles for improved performance and scalability.

Option	Description	Default Value
`--tile-matrix=<columns,rows>`	Export data in a grid of specified dimensions. Example: `2,2`.
`--tile-dimension=<width,height>`	Define tile dimensions in the database CRS grid.
`--tile-extent=<extent>`	Define the tiling extent: `x_min,y_min,x_max,y_max[,srid]`.
`--tile-origin=<origin>`	Tile origin for indexing: `top_left`, `bottom_left`.	top_left

Database Connection Options¶

The CityDB Tool requires a connection to a 3DCityDB database for all operations, including the delete command. Database connection details, such as host, port, schema, and credentials, must be provided to ensure the tool can interact with the database successfully.

These options are shared across all commands in the CityDB Tool, as a connection is essential every time data is queried, deleted, imported, or exported.

For details on how to configure database connections, including host, port, schema, and credentials, refer to the Database Connection Options documentation This section provides a comprehensive explanation of all available connection parameters.

Examples¶

Basic Export¶

Export using default settings and specifying an output file:

citydb export citygml -o output.gml
citydb export cityjson -o output.json

Stop Execution on Errors (--fail-fast)¶

Stop the export process immediately upon encountering an error:

citydb export citygml -o output.gml --fail-fast
citydb export cityjson -o output.json --fail-fast

Exporting with Custom Temporary Directory¶

Specify a custom directory for storing temporary files during the export:

citydb export citygml -o output.gml --temp-dir=/path/to/temp
citydb export cityjson -o output.json --temp-dir=/path/to/temp

Export with custom CRS and CRS Name¶

Export data using a custom CRS and include the CRS name in the output:

citydb export citygml -o output.gml --crs=4326 --crs-name=WGS84
citydb export cityjson -o output.json --crs=4326 --crs-name=WGS84

Export only CityFurniture features with a limit of 5:

citydb export citygml -t CityFurniture --limit=5 -o filtered_output.gml
citydb export cityjson -t CityFurniture --limit=5 -o filtered_output.json

Using Tiling Options¶

Export data into a 2x2 grid of tiles:

citydb export citygml --tile-matrix=2,2 -o tiled_output.gml
citydb export cityjson --tile-matrix=2,2 -o tiled_output.json

Using Configuration Files¶

Store export options in a file and reference it in the command:

citydb export citygml --config-file=export_config.json
citydb export cityjson --config-file=export_config.json