OpenStreetMap Quality Analysis Tools
TANGLE Classification of angles / geometries based on degree tolerance vs Angles analysed
| Angle | Tolerance +-2 | Tolerance +- 5 | Tolerance +- 10 |
|---|---|---|---|
| 180 | ignored | DD | |
| 90, 270 | Q | QQQ | |
| 45, 135, 225, 315 | H | HH | |
| Regular (octo, etc) | R | RR | |
| Otherwise IR |
ways_topology ( id bigint NOT NULL, id_b bigint, teval text, eval jsonb)
- id : OSM id of the polygon
- id_b : OSM id of the second polygon (Topological Analysis)
- teval : FB (Geometry form warning), XB-XO Topological Errors
- eval : Json list with various metrics to analyse the polygon
The Eval Json list contains the following keys:values:
- grp_tag: building or other
- flag = 0 , regular polygon
- flag = 1 , Irregular forms and Invalid topology
- nb_points: polygon number of points
- nb_angles: number of angles
- type_angle_list : Polygon list : Geometry evaluaiton of each Angle tangle =[r, r, rr, ir, qq, qqq, etc]
- type_geom : Polygon : Geometry summary, type_angle ex: [r-rr-qq-qqq-ir]
- type_polygon : Polygon Classified from Irregular to Regular (Starts from Geometry further from Regular with symbols [r-ir])
- Invalid
- Open
- Small (less then 4 angles)
- Micro (less then 2m2)
- ir (for [q-h-hh-qqq-ir]
- rrr (for [q-h-hh-qqq]
- rr (for [q-h-hh-dd]
- r (for [q-h-r]