Check and Build Topology

Feature Description

Data Model and Topology Analysis

SuperMap supports topological construction and inspection of editable chart groups to ensure the accuracy and consistency of chart data.

In the S-57 chart data model, objects are categorized into two types:

  • Feature Objects: Describe non-positional information of real-world entities with attribute data but no geometry information. Their geometric shapes and positions depend on spatial objects.
  • Spatial Objects: Contain geometric positional information of real-world entities and may include attribute data to describe spatial characteristics.

Feature objects derive their geometry and position through relationships with spatial objects, forming chart topology. According to Electronic Navigational Chart (ENC) specifications, node-chain-level topology must be established for spatial objects. SuperMap supports node-chain-level topological structures, with spatial objects mainly including three types:

  • Isolated nodes
  • Connected nodes
  • Edges

Each edge must start and end with connected nodes. Closed edges share the same connected node. Reference rules for feature objects are as follows:

  • Point Feature Objects: Reference isolated nodes or connected nodes
  • Line and Area Feature Objects: Reference connected nodes and edges

Key Rules for Topology Validation

Topology validation ensures chart data complies with specifications and maintains integrity. Key checks include:

  • Identifier Uniqueness Check: Verifies uniqueness of Feature Object Identifiers (FOID), Record Identifiers (RCID), and RCIDs for spatial lines, connected nodes, and isolated nodes.
  • Reference Validity Check: Ensures spatial lines correctly reference spatial points and are referenced by feature objects, connected nodes are referenced by spatial lines, and isolated nodes are referenced by point feature objects.
  • Geometric Accuracy Check: Confirms correct coordinates and spatial object references for all point, line, and area feature objects.
  • Other Rule Validations: Includes correctness of orientation, usage, and mask attributes.

Steps

  1. In chart data editing mode, navigate to the Chart Tab -> Data Inspection group -> click the Topologically Check and Build button.
  2. In the Topologically Check and Build dialog, set the datasource and editable chart group to be inspected.
  3. Click OK to perform topology validation. After modifying or creating new chart data, rebuild topological relationships to ensure logical consistency. This process creates spatial objects and establishes reference information between feature objects and spatial objects. The system will automatically rebuild topology (removing existing topology and reconstructing it).
  4. Results will display in the Output Window. If errors exist, the Topology Error Details panel will appear on the right, showing Topology Error List, Associated Feature Object, and Details.
  5. Select an error in the list or a referenced object in the associated feature object list to automatically locate and highlight the error on the map. Use information in the Details section to make corrections. For common errors and solutions, refer to: Common Topology Error Handling.

Related Topics

Chart Data Storage

S-58 Data Inspection