How the volumes are checked
- Solids with exact answers. A pyramid (100 m³ exactly), a sloping plane (12,500 m³ of cut and of fill), depth bands (4,500 / 3,500 / 2,500 / 1,500 / 500 m³), a boundary clip (10,416.67 m³) and a sphere cap (within 0.001%) are built as surfaces and their volumes compared with the formulas.
- Batters. Square and L-shaped pads in cut and in fill match A h + P k h²/2 plus the corner terms exactly, and pads on a slope agree with a fine grid to 0.5%. No batter triangles overlap.
- Every element. Pads (formation and working space), trenches (L x w x d, falling inverts, battered sides), roads (level, crowned, to formation, round a bend), ramps, bunds, ponds and stockpiles (the prismoidal formula), walls and soft spots, each against its hand formula.
- Overlaps. Two platforms whose batters overlap are compared with a brute-force integral of the upper surface on a 5 cm grid: within 0.5%.
- Three methods. Each report shows the exact overlay beside the grid method and average end areas for the same design, so the differences can be seen.
The automated checks
| Suite | What it checks | Checks |
|---|---|---|
| Engine | Triangulation, breaklines and boundaries, exact volumes against closed forms, depth bands, strata, the grid and end-area methods, platforms with batters, speed | 37 |
| Imports and exports | CSV in every common layout, DXF entities and layer roles, LandXML read and round trip, ASC and GeoTIFF grids, LAS 1.0-1.4, thinning, contours | 38 |
| Elements | Vertical curves, pads, trenches, roads, ramps, bunds, ponds, stockpiles, walls, soft spots, the composite, topsoil strip, strata, boreholes, the balance, least-cost haul and mass haul | 34 |
| Total | 109 |
As well as these, the app is driven in a browser before each release: every view, every element type, every output (PDFs, Excel, LandXML, DXF, IFC, CSV) and the free version's limits, with no errors allowed. The IFC files are checked with IfcOpenShell. The numbers in the 16 how-to guides on this site were read from the app's own results, and each guide's video was recorded by a script driving the real app.
Speed
A ground surface of about 200,000 triangles is built in about 70 ms, and its volumes against a design in about 100 ms, in the browser.
What hasn't been checked yet
- A comparison with a contractor's measured final account on a real job.
- Very large drone point clouds (tens of millions of points): they're thinned on import, which is checked, but big files haven't been timed.
- Ponds and stockpiles with very irregular outlines are triangulated from a fine grid of points, so they agree with the prismoidal formula to about 1%, not exactly.
If you have a job you'd be happy to compare, we'd like to hear from you.