Generate Mesh+
The "Mesh+" concept pursues the goal of turning conventional mesh models without semantics into queryable 3D objects (cf. figure). In this way, the advantages of queryable CityGML models can be easily combined with the photorealism of 3D meshes. This concept is now widely used, for example in the cities of Stuttgart and Bonn.
Mesh+ are created in the PlexMap Switchboard and extend an existing 3D mesh e.g. with semantics from CityGML. The result are queryable and photorealistic 3D models in the viewer.
![Mesh_Plus_1_1](/sites/frontend/files/styles/max_325x325/public/media/2023-04/mesh_plus_1_1.png?itok=3rmCICv4)
Connect the mesh model and attributes Anchor
Initially, 2D building floor plans of type Feature are required as a data source. Depending on which attributes the Mesh+ is to display later, ALKIS, OpenStreetMap or CityGML data, for example, can be used to generate the Mesh+.
In the case of CityGML data, the two-dimensional outline of the 3D buildings must first be created using the Outline function.
Since in 3D meshes e.g. roof overhangs and balconies regularly extend beyond the outline of the buildings, a buffer of about 1 meter should be placed around the 2D data. Use the Buffer function for this purpose. Then the buffered 2D data is stored in a Layer of type MapProxy.
When creating the layer with Store in Layer, the buffered 2D data must now be colored completely transparent under "style" so that they are later invisible in the viewer. To make the 2D polygons appear transpart, the alpha value of the fill color and the line color are each set to 0%.
The Layer created in this way can then be loaded into the View with the Mesh model. Please do not forget to set the Layer to "queryable" in the Layer menu of the view configuration.
Now the stored attributes can be queried in the 3D viewer by clicking on the mesh. If necessary, you can also style the query window that appears (e.g. rename or hide attributes). You can learn how to do this in the tutorial Styling the Selection window.