Project: QGIS
Version: 2.14.0
When features are required to be processed in a particular order, this can be specified by using an arbitrary expression.
This can be configured in the layer's symbology configuration dialog and can be a simple field or a complex expression.
It also provides control over ascending or descending order as well as if NULLs are first or last.
If possible, the request will be sent to the database (This depends on the complexity of the expression as well as the provider for the layer). If it is not possible to send the request to the database, the ordering will be performed on the local machine.
This is used by the 2.5D renderer to render features based on their distance from the "camera".
This is also available for plugins:
layer.getFeatures( QgsFeatureRequest().setOrderBy( 'name' ) ) -- alphabetical by name
This feature was developed by: Matthias Kuhn at OPENGIS.ch This feature was funded by: Regional Council of Picardy, ADUGA, Ville de Nyon, Wetu GIT cc
This feature was developed by Matthias Kuhn, OPENGIS.ch