EarthWorkQ QGIS 4 compatibility

EarthWorkQ integrates cut and fill volumes between a surveyed existing ground surface and a design formation over one or more polygons, and solves for the formation level at which a site balances. METHOD. All elevation inputs are reduced to a common aligned grid. Boundary cells are area-weighted by rasterising the area of interest at a sub-cell resolution (8x8 by default) and block-averaging, rather than being included or excluded whole on a centre-in-polygon test, which otherwise introduces an error proportional to the site perimeter. Volumes are the coverage-weighted sum of the signed depth field over cell area. No engine extrapolates: cells outside the convex hull of the survey, or beyond the outermost contour, are returned as nodata, excluded from the quantities, and reported as an area shortfall. VOLUME CONVERSION. Cut and fill are related by conservation of the volume of solids, V_solids = V_total / (1 + e), giving a shrinkage factor of (1 + e_in-situ) / (1 + e_compacted). Material may be specified by void ratios, by dry densities, or by an in-situ density with a compaction requirement as a percentage of Proctor maximum dry density. Water content is excluded from the volume balance, since it is not conserved through conditioning and compaction; it is used only for conditioning water volume, haulage mass, and validation that the implied degree of saturation S = w.Gs/e does not exceed unity. An optional loose void ratio gives bulked haul volume; an optional topsoil strip depth is reported separately and offsets the earthworks surface. INTERPOLATION. Engines are swappable and filtered by input type: Clough-Tocher and linear Delaunay TIN, thin-plate RBF with tension and smoothing, inverse distance weighting, nearest neighbour, GRASS v.surf.rst, GRASS r.surf.contour, and the native QGIS TIN. Ten-fold cross-validation runs over every applicable engine and reports RMSE, MAE, bias and maximum error, so the interpolator is selected by measurement rather than by assumption. Contour input defaults to r.surf.contour, which distance-weights between bracketing contours rather than triangulating vertices and so avoids the flat-triangle artefacts that produce level hilltops and valley floors. Contour topology is validated for crossing lines at differing elevations, and polylines are densified before fitting. BALANCE ANALYSIS. Sorted cumulative sums of the coverage-weighted ground elevations reduce cut and fill at any level to a binary search, making a full sweep effectively free; the balance level satisfying cut = SF x fill is then found by bisection on a monotone function. The level of minimum total earthmoving is reported alongside it. VERIFICATION. A grid convergence test recomputes quantities at half and a quarter of the chosen cell size. Where the design surface is planar, an independent exact TIN prismatic integration is performed, with triangles straddling the zero plane split at the intersection and integrated in closed form. Interpolation RMSE is propagated to an indicative volume uncertainty. INPUTS. CSV or XLSX table of easting, northing and elevation; point layer with elevation from an attribute or geometry Z; contour polylines; or an existing DEM. Design surfaces may be a flat formation level, a sloped plane defined by a spot level and grades in X and Y, or a design DEM. All inputs must be in a projected CRS in metres or feet. ROAD CORRIDOR. A second tool computes earthworks along a proposed centreline by end area between chainages, using the prismoidal rule V = L/6 (A1 + 4 Am + A2) with Am taken from a section genuinely cut at the mid chainage rather than averaged; average end area is available where a specification mandates it. A cross-section template with carriageway, camber, median, shoulders, side ditch and cut/fill batters is swept along the alignment, with superelevation and carriageway widening read from chainage tables and interpolated so the runoff is modelled. Each batter is daylighted - run out from the shoulder hinge at its gradient until it intersects existing ground - and the resulting catch point defines the earthwork footprint and the land take. A drain is formed only where there is cut depth to contain it. Earthworks are measured to the subgrade beneath the pavement build-up, with quantities to finished level reported alongside and the difference given as the pavement volume. The vertical profile comes from the Z of a 3D centreline or from a chainage/level CSV that may also carry a vertical curve length per intersection point, fitting a parabolic curve; the whole grade line can be solved to the level at which the corridor balances after shrinkage. Existing ground is sampled along every section once and cached, which is what makes that solve practical. The mass haul curve is accumulated in bank measure, so a return to an earlier level marks a real balance point, and free haul and overhaul are reported from it. GNSS AND DXF INPUT. A CSV exported from an Emlid Reach or similar receiver is filtered on its own solution status and RMS columns: observations without a fixed RTK solution, or outside a stated vertical or horizontal RMS limit, are excluded and what was removed is reported. Choosing the ellipsoidal height column in place of the orthometric elevation is detected and refused. A DXF is read for its 3D entities, with 3D polylines densified as breaklines so that hard edges survive into the surface. OUTPUTS. Signed cut/fill depth raster with a diverging ramp centred on zero, existing and design surface rasters, cut/balanced/fill zone polygons, depth contours, per-polygon quantities as CSV and as layer attributes, balance curve and area-elevation charts, and an HTML calculation report recording every input, assumption and check. The engine is also exposed as three Processing algorithms for model builder, batch and PyQGIS use.