Volume calculation

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This interface is used to calculate the volume between a surface and an elevation, or between two surfaces. The surfaces must have an outline. After calculating volume, a report appears in the preview, which can be viewed or saved as needed.

There are two options for calculating volume. Triangulation projects each surface onto the other in order to create a tighter triangulation on each surface, and create tetrahedrons with the generated triangles. It also takes the surface intersections into account for a more precise calculation. One option is used to take the breaklines into account in the calculation, for a more accurate but slightly slower result, and another option converts all of the triangles' lines into breaklines in order to more accurately represent the original surfaces. The latter is the most accurate possible method for replicating the original surfaces, but is much slower. The nearest neighbor method creates a grid on the surface and generates prisms between the two grids in order to calculate the volume. This solution is faster, but less accurate.

It is also possible to generate the surfaces resulting from that calculation through triangulation, in order to be able to assess the interpolation created by the calculation and to generate much denser surfaces. Each surface created will have the name of the previous surface preceded by "Vol_" and will have the outline of the previous two outlines' intersection.

It's also possible to generate differential contours, which are contours that indicate the difference between the two calculated surfaces. The parameters of these contours are defined in the contour preferences, as mentioned above.

Additionally, it is possible to calculate the volume inside a polygon formed by closing a selected polyline rather than basing it on the intersection of the contours' areas.

Function	Description
Reference surface	Existing surface: A defined surface with which the comparison is being made. Z levels: Flat surface at the given elevation.
Volume calculation method	By Triangulation – A reverse prism method with the option of keeping the breaklines and converting all the triangle sides into breaklines. By Grid – A cubic method in which the grid parameters are specified as chosen.
Swell	The factor by which the porosity of the soil increases, accompanied by the fracturing of the aggregates due to various influences: freezing, tilling, etc., leading to a temporary increase in volume.
Draw grids or triangles	Draws the grid or triangles in the main window based on the calculation method. The button next to the option is used to erase the result of the main window.
Save resulting surfaces	Used to save in the list of surfaces the portion shared between two surfaces based on which volume was calculated (intersection of two surfaces).
Make differential contours	Draws the contours of the difference in elevation between the two surfaces. The parameters of these contours are defined in the contour preferences.
Delimit volume	When checked, the button can be used to pick a polyline on the drawing in order to delimit the surface used to calculate the volume.