Examples
Examples
Try the starting example
- JSON Roof sections [ID,simple polygon vertices [x m,y m]]
- [["A",[[0,0],[10,0],[10,10],[0,10]]]]
- JSON Defects [ID,section ID,simple polygon vertices [x m,y m]]
- [["D1","A",[[1,1],[3,1],[3,3],[1,3]]],["D2","A",[[5,5],[7,5],[7,6],[5,6]]]]
- Section [ID,area m²,repair m²,repair fraction]
- [["A",100,6,0.06]]
- Total defect area (m²)
- 6
- Defect areas [ID,m²]
- [["D1",4],["D2",2]]
Try another scenario
- JSON Roof sections [ID,simple polygon vertices [x m,y m]]
- [["A",[[0,0],[10,0],[10,10],[0,10]]]]
- JSON Defects [ID,section ID,simple polygon vertices [x m,y m]]
- [["D1","A",[[1,1],[4,1],[4,3],[1,3]]]]
- Section [ID,area m²,repair m²,repair fraction]
- [["A",100,6,0.06]]
- Total defect area (m²)
- 6
- Defect areas [ID,m²]
- [["D1",6]]
Calculation method
Calculation method
Section [ID,area m²,repair m²,repair fraction]
Shoelace section/defect areas; sum nonoverlapping defect polygons per section.
Total defect area (m²)
Sum absolute shoelace defect areas.
Defect areas [ID,m²]
0.5 × absolute(sum cross products of consecutive vertices including closing edge).
Symbols and units
- a
- JSON Roof sections [ID,simple polygon vertices [x m,y m]]
- b
- JSON Defects [ID,section ID,simple polygon vertices [x m,y m]]
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- Convex polygon vertices in common planar metre coordinates; defects must lie within their section and have disjoint interiors. Input validation must reject self intersections, overlaps, and outside defects; no severity assessment. Supported limits: At most 20 sections/100 defects, 3–100 vertices each, convex polygons only, no holes; boundary-touching polygons allowed.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.