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21. Les Tuiles 3D
21.1. Que sont les tuiles 3D ?
3D tiles are specification for streaming and rendering large-scale 3D geospatial datasets. They use a hierarchical structure to efficiently manage and display 3D content, optimising performance by dynamically loading appropriate levels of detail. This technology is widely used in urban planning, architecture, simulation, gaming, and virtual reality, providing a standardised and interoperable solution for visualising complex geographical data. Read Using 3D tiles services for more details.
Fig. 21.1 Exemple de tuiles 3D
21.2. Sources de données
Prise en charge de tuiles 3D :
Source distante -
http://example.com/tileset.jsonFichiers locaux -
file:///path/to/tiles/tileset.json
21.2.1. Utilisation de données de Cesium ion
Cesium ion is a cloud-based platform for managing and streaming 3D geospatial data. It simplifies data management, visualisation and sharing. To add 3D tiles from Cesium ion, you need to first sign up to their service here: https://ion.cesium.com.
You can also use Cesium ion plugin from the QGIS repository to add the data to QGIS.
21.2.2. Using Google 3D data
To use Google Photorealistic 3D tiles in QGIS, get an API key for 3D tiles. Once you have the key, simply add Google tiles using the same connection process.
Fig. 21.2 Google 3D Tiles connection
21.3. Propriétés de tuiles 3D
La fenêtre Propriétés de la couche des tuiles 3D propose les onglets suivants :
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[1] Aussi disponible dans le panneau Style de Couche
21.3.1. Onglet Information
The Information tab is read-only and represents an interesting place to quickly grab summarized information and metadata on the current layer. Provided information are:
Basé sur le fournisseur de la couche : no, URL, type et chemin de la source de données, nombre de niveaux de zoom
Le système de coordonnées de référence : nom, unités, méthode, précision, référence (c’est-à-dire statique ou dynamique)
picked from the filled metadata: access, extents, links, contacts, history…
21.3.2. Onglet Source
The 
Source tab displays basic information about
the selected 3D tile, including:
le nom de la couche à afficher dans le panneau couche;
the Coordinate Reference System: Displays the layer’s Coordinate Reference System (CRS). You can change the layer’s CRS, by selecting a recently used one in the drop-down list or clicking on the
Select CRS button (see Sélectionneur de Système de Coordonnées de Référence).
Use this process only if the layer CRS is wrong or not specified.
21.3.3. Onglet Symbologie
Fig. 21.3 3D Tile Layer Symbology
By default, the layer is styled using texture, but you can change it
to see the wireframe mesh behind the scene by choosing Wireframe
in the drop-down menu. You can also, change the mesh fill and line symbols
similar to the vector polygons.
Checking 
Use texture colors will render each mesh element
with the average value of the full texture.
This is a good option to try when dealing with a large dataset and
want to get a quick overview of the data.
Fig. 21.4 3D Tiles - textured and wireframe
To view the data you can open 
New 3D map view.
Fig. 21.5 Vue 3D
From the Symbology tab, you can also set some options that invariably act on all features of the layer:
Maximum error: This parameter determines the level of detail displayed in the 3D model. Similar to point clouds, 3D tiles often contain more information than necessary for visual representation. By adjusting this setting, you control the balance between display density and rendering speed. A larger value (e.g., 5 mm) may introduce noticeable gaps between elements, while a smaller value (e.g., 0.1 mm) could lead to the rendering of an excessive number of details, potentially slowing down the rendering process. Different units can be selected to tailor the setting to your specific needs.
Opacity: Adjust the visibility of the underlying layer on the map canvas using this tool. Use slider to tailor the visibility of your scene layer according to your preferences. Alternatively, specify the exact percentage of visibility through the menu next to the slider.
Blending mode: You can achieve special rendering effects with these tools that you may previously only know from graphics programs. The pixels of your overlaying and underlaying layers are mixed through the settings described in Modes de fusion.
21.3.4. Onglet Vue 3D
Maximum screen space error determines the threshold for swapping terrain tiles with more detailed ones (and vice versa) - i.e. how soon the 3D view will use higher quality tiles. Lower numbers mean more details in the scene at the expenses of increased rendering complexity.
Show bounding boxes Show 3D bounding boxes of the
terrain tiles (useful for troubleshooting terrain issues).
21.3.5. Onglet Rendu
Under Scale dependent visibility,
you can set the Maximum (inclusive)
and Minimum (exclusive) scales,
defining a range of scales in which features will be visible.
Out of this range, they are hidden.
The 
Set to current canvas scale button helps you
use the current map canvas scale as boundary of the range visibility.
See Sélecteur de visibilité définie par l’échelle for more information.
21.3.6. Onglet Élévation
The 
Elevation tab provides options to control
the layer elevation properties within a 3D map view.
Specifically, you can set:
Elevation Surface: how the 3D layer vertices Z values should be interpreted as terrain elevation. You can apply a Scale factor and an Offset.
21.3.7. Onglet Métadonnées
L’onglet 
Métadonnées vous offre des options pour créer et modifier un rapport de métadonnées sur votre couche. Voir Métadonnées pour plus d’informations.