Bentley's ContextCapture has various output options that can be imported into TerraExplorer and then converted to Skyline's stream optimized, 3DML mesh layer format. For best performance especially for large scale projects, Skyline recommends using ContextCapture's Cesium 3D Tiles output option. We also strongly recommend running LOD generation from ContextCapture on the Cesium 3D Tiles output.
Following these two recommendations enables the data to be efficiently displayed within TerraExplorer for Desktop, as well as streamed by SkylineGlobe Server to TerraExplorer for Desktop, Web, and mobile clients, and other clients, such as Cesium, ESRI, QGIS, Unreal Engine and other 3D visualization apps.
In this article, we cover best practices for ContextCapture Cesium output, and outline the steps for importing the Cesium data and converting it to Skyline's stream-optimized, 3DML mesh layer format in TerraExplorer.
In ContextCapture:
- Select Cesium 3D Tiles as the output format.
- In production Format/Options, set the following settings:
- In Level of detail, select the Scope based on project size:
- Across tiles - Preferred level-of-detail mode for large-scaled models to create a quadtree across all tiles of a reconstruction instead of an independent LOD tree for each tile.
- Tile-wise - Recommended for small mesh, buildings, bars, towers, bridges, etc., for close-range LOD (creates LOD per tile).
- From the production interface, click Run LOD generation.
- If using ContextCapture version 16, automatic LOD creation does not work, so manual editing of the generateLOD.bat file is required. If using this version, in the production's output directory, right-click the generateLOD.bat file, select Edit, and then set the following parameters (click here for more information). Note, if you are not using ContextCapture version 16, skip steps 5-7.
- scene - Change to the real production name
- format - Set to the relevant one (3sm or 3mx)
- tileOverlap - Set to the actual value of this production
- tilingSRS and outputSRS - Check that they are set to good values
- jobFile "path\task_def_0.bin" - Delete this information
- Save the .bat file. Make sure that the file tiles.txt contains all the tiles for this production.
- Run the GenerateLOD.bat file by double-clicking on it.
- At the end of the production process, a "scene" folder containing Cesium tiles with LOD is created.
In TerraExplorer:
- Open TerraExplorer for Desktop and open any project.
- On the Layers tab, from the Load 3D Mesh drop-down list, select Import 3D Tiles Layer.
- Input the *.json file from the Scene folder created at the end of the ContextCapture production process.
- Make sure to input the correct coordinate system information for your ContextCapture project including the Vertical Datum information. The output coordinate system of the Cesium 3D Tiles is ECEF.
- Click Create. The created 3DML is added to the project and displayed in the Project Tree.