Generic Areas

This Subflow provides basic area generalisation capabilities.

The following parameters are defined on the Generic Area theme:

Parameter	Description	Default Value
SimplificationPriority	When a simplification or smoothing algorithm is applied to shared links, the link will be simplified by the feature with the highest priority value.	1
TopologyPriority	Priority used during the topological structuring. Lower priority features will be snapped to higher ones.	1
MinArea	The area in square metres below which an area feature will be deleted.	50m2
MinHoleArea	The area in square metres below which a hole in an area feature will be filled in.	50m2
WeightedEffectiveAreaMinimumArea	The threshold in square metres for the weighted effective area algorithm.	150m2

Steps Used by The Generic Area Subflow

1. Delete Small Holes and Small Generic Areas

   This action fills in the holes smaller than MinHoleArea in area features, and then assesses the size of the feature. If it is less than MinArea, the feature is deleted.

2. Apply Weighted Effective Area On Generic Area Links

   This action simplifies the boundary of the area features, taking care of shared boundaries (as explained in Line_Simplification_Group).

3. Re-apply Weighted Effective Area On Failed Edges

   This reprocesses features that failed to simplify in the previous step (as explained in Line_Simplification_Group

4. Delete Small Holes and Small Generic Areas (2)

   This step is similar to step 1, it processes features which may have become too small as a result of the simplification.

5. Set Generic Area ID

   This action assigns a random unique ID to features which have a null ID.