4.4.4. Bounding box filter¶

The bounding box filter takes a 2D bounding box as parameter that is given by the coordinate values of its lower left (x_min, y_min) and upper right (x_max, y_max) corner. The bounding box is evaluated against the gml:boundedBy property (CityGML) respectively the “geographicalExtent” property (CityJSON) of the input features. You can choose whether features overlapping with the provided bounding box are to be imported, or whether features must be inside of it.

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Fig. 4.16 Bounding box filter for import operations.

Make sure to choose a coordinate reference system from the drop-down list that matches the provided coordinate values. Otherwise, the spatial filter may not work as expected. The coordinate reference system list can be augmented with user-defined reference systems (see Section 4.7.2 for more information).

The coordinate values of the bounding box filter can either be entered manually or chosen interactively in a 2D map window. To open the map window, click on the map button map_select .

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Fig. 4.17 Bounding box selection using the 2D map window.

In the map window, keep the left mouse button clicked while holding the ALT key. This lets you draw a bounding box on the map. In order to move the map to a specific location or address, simply enter the location or address in the input field on top of the map and click the search button map_search or use the map navigation controls. If you are happy with the bounding box selection, click the Apply button. This will close the map window and copy the coordinate values of the selected area into the corresponding fields of the bounding box filter and set the reference system to WGS 84. Click Cancel if you want to close the map window but skip your selection. A more comprehensive guide on how to use the map window is provided in chapter Section 4.8.

With the bbox_copy button on the bounding box filter dialog, you can copy a bounding box to the clipboard, while the bbox_paste button pastes a bounding box from the clipboard to the input fields of the bounding box filter (or use the right-click context menu).