CanVec: Geometric Model
Canvec Product - geometric model
The proposed geometric model provides a partial integration of geometries. This is a compromise between a fully integrated model and a self-contained geometry model.
Self-contained model: all geometries are complete by themselves. Overlapping lines segments are duplicated. Coordinates (nodes) at intersections are also duplicated. The model however allows the selection of a subset of entities for data import. A disadvantage is that it isn't possible to use polygons with holes.
Full integration model: none of the geometries is duplicated, including nodes. All adjacent entities must however be formed by relations - multipolygon or route type. The model does not allow the selection of a subset of entities for data import. Everything must be imported at the same time.
Partial integration model: all geometries are complete by themselves. Integration at coordinate level eliminates duplicate nodes. Overlapping lines segments are duplicated. The model however allows the selection of a subset of entities for data import.
Graphically, the proposed model can be described as below
For discussions about the proposed model, please use the Talk:CanVec:_Geometric_Model page