Instructions for use

The Generate Scene Tiles command is used to create tile files for the selected entire scene. This function does not depend on a scene, meaning it can be used directly even without an open scene window.

During Build Scene Tile, a mosaic dataset or image dataset corresponds to generating an image tile, while a terrain dataset corresponds to generating terrain tiles. If it is a tile layer (such as a model tile layer) or KML layer, it remains unchanged.

After scene tiles are generated, a new workspace and several tile folders will be created under the result path. The new workspace not only stores various newly generated tile layers but also preserves the style information of each tile layer. By default, the newly generated workspace has the same name as the scene used to generate tiles, and users can specify the name of the generated workspace and scene via set parameters.

To use this function, the computer must meet certain software and hardware requirements, which are consistent with those for using a 3D scene rendering engine. For details, refer to the 3D Scene Rendering Engine instructions for use (Windows and Linux systems).

Function Entry

• Workspace Manager->Context menu of a specific scene->Generate Scene Tiles... command

Operation Steps

1. In the Workspace Manager, right-click on a scene, select "Generate Scene Tiles..." from the pop-up menu, and the "Build Scene Tile" dialog box will appear.
2. Toolbar
   • Select All: After selecting all datasets in the data list, batch operations can be performed on the datasets, such as deletion and batch setting of tile parameters.
   • Invert Selection: Selects datasets in the data list that are not currently selected.
   • Delete: Removes the dataset from the current data list.
     Notes:

     • When batch setting tile parameters, after entering specific parameter values, you need to press the Enter key to make them effective; otherwise, it may cause the batch assignment of the same parameter values to fail.
3. Data list area:
   • Dataset: Displays the name of the data used to generate model tiles and upload.
   • Data Source: Displays the name of the data source where the data used to generate model tiles and upload is located.
   • Tile Type: Displays the type of scene tiles to be generated. Tile Type is a drop-down button; the drop-down list shows all tile types supported by the selected data, and users can choose from them.
   • Scene Type: Displays the scene type where all generated scene tiles reside. Scene Type is a drop-down button; the drop-down list shows all scene types supported by the selected data, and users can choose from them.
4. Basic settings:
   • Scene Name: Enter the tile name in the text box to the right of "Scene Name," which is the name of the tile root directory. The default name is the scene name.
   • Storage Path: Enter the export directory for tiles in the text box to the right of "Storage Path," or select a path via the "Browse" button after the text box.
5. Advanced settings:
   • Texture compression method: For tiles of different purposes, the application uses different texture compression methods to reduce the amount of video memory used by texture images.
     • WebP: Significantly reduces the total data volume; a texture compression format supported on both PC and mobile devices.
     • DXT (PC device): Reduces video memory usage and improves rendering performance but increases the total data volume.
     • CRN_DXT5 (PC): Reduces video memory usage and decreases the total data volume but requires longer processing time.
     • No Compression: Does not perform texture compression.
   • Tile Side Length: Displays and sets the size of the tile side length in meters. Different tile side lengths correspond to different scales. When data is dense and both geometry and textures are simple, set the tile side length to a larger value, such as 1000. When data is sparse and geometry or textures are complex, set it to a smaller value, such as 200.
   • Filter Threshold: Used to improve the performance of large scene data by filtering out sub-objects with smaller sizes in coarse layers. For example, if the filter threshold is set to 2, sub-objects with a longest side less than 2 meters are filtered out in the coarsest layer, less than 1 meter in the next coarsest layer, and so on. Sub-objects in the finest layer are not filtered.
   • S3M Version: Used to set the tile version, including S3M 3.0 and S3M 3.01.
     • S3M 3.0: Supports OBB bounding boxes and generates tiles based on an ellipsoid reference surface.
     • S3M 3.01: Complies with the CH/T 9040-2023 standard, supports OBB bounding boxes, and generates tiles based on an ellipsoid reference surface.
   • Attribute Storage Type: Supports S3MD and Attribute types.
     • S3MD: Stores attribute data in JSON format, enabling quick extraction of all attributes for a single object.
     • Attribute: Stores attribute data as binary streams, more suitable for data with many attributes, allowing rapid extraction of attributes for specific fields across multiple objects.
   • Repeat Map Group, Use Point-Attached External Model to Generate Tiles, Recalculate Normals, Instancing, Tangents: Can be checked based on requirements.
     • Repeat Map Group: Used to set whether to repeat the map group. During modeling, a large number of repeated texture maps are often used on a building. For example, railings and guardrails on different floors usually have the same appearance; sharing a single texture map can significantly reduce performance and resource consumption.
     • Use Point-Attached External Model to Generate Tiles: Checked by default, supports generating 3D tiles from point-attached external models. If it is an attached image, it is recommended to uncheck this.
     • Recalculate Normals: Used to set whether to recalculate normals. Check this if the data normals are incorrect. Surface normals are essential for rendering to produce lighting effects that align with visual perception. During tile rendering, rendering can be based on the model's own normals.
     • Instancing: Used to set whether the result data uses instanced storage. Instanced storage means that if object reuse exists, only one object needs to be stored in memory, and reused objects only record position, rotation, scaling, and other pose information.
     • Tangents: Used to set whether the result data has tangents. After checking, the indoor mapping technology can be applied to the resulting S3M data in Unreal Engine to simulate indoor effects.
6. By default, "Auto Close When Finished" and "Show Progress Bar" are checked; they can be unchecked.
7. After completing the settings, click the "OK" button to execute the scene tile generation operation.

Differences from Build 3D Tiles

The context menu provides two ways to build 3D tiles: one is through the "Generate 3D Tiles..." command in the dataset context menu, and the other is through the "Generate Scene Tiles..." command in the scene context menu, which generates tiles for all data in the entire scene. They differ in operation and output, so please use them appropriately in practical applications.

The differences are as follows:

1. The "Generate 3D Tiles..." command is located in the context menu of dataset nodes in the Workspace Manager; the "Build Scene Tile" command is in the context menu of scene nodes in the Workspace Manager and requires the current workspace to have an existing scene.
2. "Generate 3D Tiles..." allows manual addition of data for tile generation; the entire scene tile generation can only generate tiles for existing datasets in a specific scene and cannot add other datasets not present in the scene.
3. When viewing the results of scene tile generation, you need to open each tile file corresponding to each layer individually; the entire scene tile generation creates a workspace that saves the styles of each layer in the scene. To view the results, simply open the workspace of the entire scene tile, and the styles will be displayed.