3D mesh

Produce a 3D model optimized for visualization and analysis in third-party software.

Output formats

Proposed 3D mesh formats are:

Note: Refer to Software Editions table to verify what output formats are the supported specifically by your edition.

3MX format: an open format that we propose in order to facilitate the distribution of ContextCapture data. It can be used for:
- Web publishing, by using our free ContextCapture Web Viewer, you can publish or embed 3D models in your web site.
- Interoperability with other Bentley Systems products, such as ContextCapture Web Viewer and MicroStation.
- Interoperability with third-party applications (3D GIS).
For more details about the 3MX format, see the format specifications in the ContextCapture installation directory.
Bentley Scalable Mesh (3SM): file format suitable for display, analysis and editing of large 3D meshes in Bentley design applications.
3SM 3D Tiles format can be directly displayed online in a 3D web viewer once published to ProjectWise ContextShare. See Publish to ProjectWise ContextShare.
Smart3DCapture S3C (deprecated): Legacy format of ContextCapture , with compression, dynamic level-of-detail and paging.
S3C format is optimized for local or online navigation of entire reconstructions in real time with ContextCapture Viewer.

S3C scenes can be edited with ContextCapture S3C Composer.
OBJ wavefront format: A portable 3D format that can be loaded by most CAD and 3D software.
In this format, a single-level high resolution 3D mesh is proposed by default, but ContextCapture can generate level of detail if needed.

OBJ productions can also be published to Sketchfab. See Publish to Sketchfab.
Bentley DGN: Native 3D format of MicroStation and other Bentley CAD application.
Collada DAE: Interchange file format for interactive 3D applications.
Autodesk FBX: 3D exchange format for Autodesk applications.
Stereolithography STL: Geometry format widely used for 3D printing (does not support texture).
ESRI i3s scene database: ESRI Indexed 3d Scene format for ArcGIS Scene Service.
This format is used to stream 3D GIS data to ESRI mobile, web and desktop clients. It's supported from ArcGIS Server version 10.3.1, ArcGIS Pro version 1.1 and ArcGIS SceneViewer version 3.7/10.3.1.

It is recommended to produce with default options. Once the production is completed, Create a scene package (SLPK file) to get a single file easy to use with ESRI applications.
Cesium 3D Tiles format, suitable for display in Cesium. More information on Cesium.
Google Earth KML: Hierarchical file format suited for real-time 3D display of very large datasets in Google Earth.
OpenSceneGraph binary (OSGB): The native format of the open source OpenSceneGraph library, with dynamic level-of-detail and paging.
Best suited for SuperMap GIS.
SuperMap S3M: Best suited for SuperMap GIS Software.
OpenCities Planner LodTree: Interoperability format for OpenCities Planner, based on XML files and 3D models in Collada format.
LOD tree export: a level-of-detail tree exchange format, based on XML files and 3D models in Collada DAE format.
Best suited for Eternix Blaze Terra, Agency9 CityPlanner, Skyline TerraBuilder, DIGINEXT VirtualGeo.

For more details about the LOD tree export format, see the format specifications in the ContextCapture installation directory ( ).
SpacEyes3D Builder layer: SpacEyes3D Builder layer file based on OSGB format.
Best suited for SpacEyes3D Builder.

A generic SpacEyes3D Builder GVW project file is also created.

Note: City-scale 3D models are split into tiles when using ContextCapture , and our level-of-detail (LOD) structure is generated for each tile independently. This leads to an incomplete level-of-detail structure and low loading performance if the model contains a large number of tiles. As a solution to this problem, Bentley Systems has developed a post-processing tool capable of creating the entire LOD structure. This tool is accessible through the LOD option 'Quadtree across tiles'.

Options

Enabled options for 3D mesh depend on the chosen format:

Include texture maps: include the texture or not (texture files and uv coordinates).
Color source:
- Visible colors: texture with photos with visible colors band.
- Thermal: texture with photos with thermal band. Note: use 3D View or ContextCapture Viewer Measurements tool to display temperature values on the resulting mesh.
- Resolution: texture with a color scale showing resolution of input data (either photos or point clouds).
  Note: use 3D View or ContextCapture Viewer Measurements tool to display resolution values on the resulting mesh.
Texture compression: choose the JPEG quality level (50%, 75%, 90%, 100%).
Texture sharpening: enhance mesh texture by applying a sharp filter (enabled by default), this option can be disabled to keep the initial image sharpness.
Level of detail (LOD): include levels of detail.
Type: type of LOD structure: simple levels, quadtree, octree, adaptive tree or Bing Maps Tiling System (only for reconstruction based on Bing Maps SRS).

Scope: Tile-wise (default) or Across tiles. See below.

Node size: depending on the application, a larger number of lighter LOD nodes may be more advantageous than a smaller number of heavier LOD nodes. This option allows to vary the size of LOD nodes, when using a quadtree, a octree or an adaptive tree.
Skirt: the skirt is an additional border included around each geometry node and around each tile, to avoid cracks between the different parts of the mesh.
The skirt is not tangent to the 3D model: it lies in the boundary of the 3D region of the node, and it is oriented towards the interior of the 3D model. For example, the skirt between two side-by-side mesh nodes is composed of thin vertical strips. As the skirt length is given in pixels in input photos, it adapts to the local dataset resolution.
Tile overlap: on reconstructions with tiling, an overlap between tiles is included to avoid cracks.
The overlap is given in meters (or units for non-georeferenced blocks): the overlap is uniform over the 3D model.

About the LOD Scope option 'Across tiles'

The 3D models produced by ContextCapture are divided into tiles. In its current version, ContextCapture can generate a level-of-detail structure for each tile taken independently, but only the scope option 'Across tiles' will produce global level-of- detail structure (e.g., a quadtree) for an entire reconstruction.

Such a global LOD tree is desirable for real-time 3D rendering of a wide area without constraints on viewing altitude or tilt angle. This requires the manipulation of very low resolution versions of large parts of the model, the extreme case being one small 3D mesh to represent the entire model at very low resolution.

The LOD Scope option 'Across tiles' is based on the external command line tool "ExportUniqueMesh". See also ExportUniqueMesh.

A production with LOD Scope option 'Across tiles' is made in two steps:

Production of reference 3D model.
This steps is managed as usual by ContextCapture Engines.
LOD generation.
This step must be started manually once the first step is finished:
- Either from the production interface with the command "Run LOD generation",
  
  In this case, the LOD generation happens on this computer.
  
  Note: The LOD generation is not managed as usual jobs by ContextCapture Engine, but in a dedicated command line tool running in a command prompt.
- Or with the command script 'generateLOD.bat' available in the production's output directory.
  In this case, the LOD generation can be started and processed from any computer, and even from several computers in parallel (on computers equipped with ContextCapture Engine).