Documentation of QGIS Python plugin brdrQ: FeatureAligner

Instructions

  1. Choose the settings for the alignment (reference layer,…)
  2. Select the thematic layer you want to align.
  3. Select a feature from the list or via ‘Select feature(s) on map’.
  4. View the prediction(s) for this aligned feature.

Additionally, you can:

  • Switch between multiple predictions (via list, slider, or spinbox).
  • Plot: Request a ‘plot’ of these predictions (relevant distance (m) vs. change (m²)).
  • Visualize: Visualize the predicted relevant distances side by side.
  • Save Geometry: Adjust the original geometry to the chosen prediction.
  • Reset Geometry: Reset the original geometry (only within a feature session, so if no other feature is selected).

Settings

  • Choice of the reference layer: you can choose a local layer or several predefined on-the-fly layers (GRB, OSM,…)
  • OpenDomain Strategy: exclude or include the Open Domain
  • Processor: Choice of processing-algorithm. Best to use AlignerGeometryProcessor (default), as this is a wrapper that chooses the fastest available algorithm based on geometry-types: DieussaertGeometryProcessor for Polygon-to-Polygon and NetworkGeometryProcessor for all other geometry-type-combinations.
  • Threshold_overlap_percentage (default 50): fallback value for the algorithm if no relevant areas are detected.
  • Maximum relevant distance: Maximum distance (in meters) that can be used to search for predictions. (Prediction deviates at most by this value from the original).
  • Add metadata: A field ‘brdr_metadata’ with descriptive metadata of the geometry is added to the result.
  • FullReference Strategy: Choice that determines the score of the predictions based on a full overlap with reference polygons:
    • ONLY_FULL_REFERENCE: Only predictions with a full reference overlap are shown.
    • PREFER_FULL_REFERENCE: Predictions with a full reference overlap get a higher score, others are still shown.
    • NO_FULL_REFERENCE: No distinction is made between predictions with or without full reference overlap.
  • SNAP OPTIONS: only used when geometry is processed by the NetworkGeometryAligner (Line or Points):
    • SnapStrategy:
      • NO_PREFERENCE: does not prefer real vertices when searching for a solution
      • PREFER_VERTICES: tries to move the result to real vertices of the reference data if they are within relevant distance
      • ONLY_VERTICES: uses only real vertices of the reference data (or not, if not found)
    • Segmentize: <No effect, can be ignored>