To navigate from one feature to a linked feature, it is necessary to set up so-called “projections”. A certain level of prior experience and knowledge of the data model is strictly required for creating them. Further information on where these can be found in Map3D can be found here.
Setting up projections
The projections can be accessed via the corresponding tab in the project settings. Creating a new route is possible via the button “Create a new route”. Using the button “Add standard routes”, the predefined routes
- Ducts in trench
- Ducts in ducts
Cables in duct
Building unitsand the initially disabled routes
- Cables in trench
- Ducts in ducts in trench
can be added.
Editing a projection
A projection consists of a start layer – in this example the trench tc_m_sp_segment – and a target layer – the ducts tc_m_sp_duct. Each projection requires a name. The name can vary depending on the language. The “Published” slider controls whether the projection is available to the user.
A projection consists of individual relations. Relations are small chains between the individual layers or tables. The creation of these relations is individual and must be defined according to requirements. Much of this can be derived from the projections in Map3D.
In general, a projection can be imagined like a bus line. There is a starting stop (“Start layer”) and a final stop (“Target layer”). In between are the individual stops. Two stops are connected by a journey (“Relation”).
A new relation can be added via the “Add link” button. This opens a new window in which existing relations can be selected or new relations can be defined and added.
The last target layer from the list of relations is highlighted in color in the new window. New relations can be defined via “Add new record”. Existing relations can also be edited. Caution is advised here, as changes apply to the entire project.
Warnings during creation
If there are problems with a projection, this is indicated by various warnings, for example if the target layer in the list of relations does not match the specified target layer.
Common error messages
If the target layer is not published and is not of type “WFS Dynamic”, the projection throws an error at this point. An unpublished layer should not be accessible via a projection.
Sometimes, due to personal browser settings, only the error message “The route is still empty” appears even though relations already exist in the route. In this case, the settings related to the target layer should definitely be checked.
Unpublished layers in projections
It is not possible to include an unpublished layer, as it is effectively treated as “non-existent”. One possible workaround is to publish the layer but enable “Hide in layer legend”.
Relations
Under the “Relations” tab, the individual connections can be edited. A relation consists of the following fields:
Start layer
Start attribute
Target layer
Target attribute
Attribute for sorting (if an individual sorting by name, duct position, or apartment number is desired, for example)
Sort ascending (defines the sorting direction)
Inherited (whether the relation exists in TB_RELATIONS)
TB_RELATIONS is a table in the NET data model that contains a collection of relations from NET. If the layer is published in the GeoServer, the relations stored there can be imported using the “Load links from TB_RELATIONS” button.
Configuring projection labels
The labeling is configured directly in the linked layer. For example, if ducts are to be color-coded, this must be done directly in the duct layer settings.