{"id":1552,"date":"2020-05-06T11:43:05","date_gmt":"2020-05-06T11:43:05","guid":{"rendered":"https:\/\/wetransform.eu\/?post_type=news-and-events&p=1552"},"modified":"2022-07-28T08:09:50","modified_gmt":"2022-07-28T08:09:50","slug":"bounding-box-collector","status":"publish","type":"news-and-events","link":"https:\/\/wetransform.to\/de\/neuigkeiten-veranstaltungen\/bounding-box-collector\/","title":{"rendered":"Groovy Week 2020: Building a Bounding Box using a Collector"},"content":{"rendered":"

In our third installment of the 2020 Groovy Week, we are going to cover a typical use case of hale\u00bbstudio's Collector feature: building a bounding box covering the geometries of all source objects. For an introduction to the powerful Collector feature, make sure to check out our previous post on the subject<\/a>. Like in the previous Groovy Week posts, note that this article assumes you have working knowledge of hale\u00bbstudio and know the terminology.<\/p>\n

Wednesday's Script: Building a Bounding Box using a Collector (Florian)<\/h2>\n

A typical use case for calculating a bounding box covering the geometries of all source objects is creating an alignment to the INSPIRE Species Distribution theme<\/a>. Transforming to this theme typically comprises creating several SpeciesDistributionUnit<\/code> instances and a single SpeciesDistributionDataset<\/code> instance which references those units.<\/p>\n

When creating the SpeciesDistributionDataset<\/code> instance, one of the mandatory target attributes to fill is domainExtent<\/code> which should contain the geographic extent of all contained SpeciesDistributionUnit<\/code> instances. To achieve this, we will create a bounding box covering all SpeciesDistributionUnit<\/code> geometries on the fly during the transformation using a Collector. While there exists the specialized function Compute Extent<\/code> for calculating bounding boxes, using it would require a Merge<\/code> over all source instances. Using a Collector is more efficient in this case.<\/p>\n

\"hale\u00bbstudio<\/p>\n

Instead of using the Rename<\/code> function to map the source geometry to the SpeciesDistributionUnit<\/code>, use the following Groovy script:<\/p>\n