Import a design or elevation file

Ditch Assist® reads design and elevation files made on a computer: whole-field designs for Land Forming, civil design surfaces, single-line designs and surveys, and elevation data to draw contours from. This page lists each one, where you load it, and what the file must look like. Map pictures and KML lines are overlays, not designs: see Add a map overlay.

Before you start

Time: a couple of minutes to pick a file once it's on the tablet.

• The file is in the tablet's Download folder. Copy it there by USB cable, a USB-C stick, email or Google Drive: Move files to and from the tablet. Do it on shop Wi-Fi, before you join the control module's Wi-Fi (it has no internet).
• You know which kind of file it is (table below).

Pick the file on the tablet

Every import button in the app opens Android's file picker. It fills the screen and shows one folder at a time. Here it's opened from Land Forming's Select Design File; the other import buttons open the same picker. You pick one file at a time. To leave without picking, press the tablet's Back button (The Back button).

Which file, where

Land Forming files: AGD, XYZP and XYZ

All three load through the Land Forming Design window: Select Design File (XYZ / XYZP / AGD). The app works out the format from the file itself, not from the button you tapped or the file name. AGD is the preferred format. Step by step: Land Forming.

Text layout (XYZ and XYZP)

• One point per line: latitude, longitude, elevation (XYZ), plus proposed elevation as the 4th column (XYZP).
• Latitude and longitude in decimal degrees (WGS84), for example 49.81234, -97.45678. Easting and northing are not read; those lines are skipped.
• Elevations in metres.
• Columns separated by tabs, commas, semicolons or spaces. Comma decimals (247,65) are fine with semicolon separators.
• A header line at the top is skipped. Blank lines are ignored.
• Every line of an XYZP file needs both elevations. A line with only three numbers stops the import with its line number, so existing and proposed never get out of step.
• A line containing BM, BENCH or BENCHMARK is read as a benchmark (first three numbers = latitude, longitude, elevation; the rest is its name). It shows as a Design BM when you calibrate.

Example XYZP (four columns):

In the file these are plain text, one line each, separated by tabs (or commas, semicolons or spaces). The header line is optional.

AGD

An AGD export is a comma file whose header names the columns (it must include Existing, Proposed and Code). The app reads latitude, longitude, existing elevation and proposed elevation, and uses the Code column:

Other codes are skipped.

What the summary tells you

• Points: grade points read. Fewer than you expected means lines were skipped (bad coordinates, wrong columns).
• Area: in hectares (Forming is metric). 0.0 ha means the points lie on a line: a ditch design, not a field.
• Elev Range, Min Elev, Max Elev: should match the field. Numbers in the thousands mean the file is in feet.
• Benchmarks, Sections: AGD only.
• Avg Cut (red), Avg Fill (blue): XYZP and AGD only.

Over 50,000 points isn't recommended: triangulating takes minutes and slower tablets struggle. Have your design software thin the points.

LandXML surfaces

LandXML 1.2 with a TIN surface (points and triangles). Forming takes a design surface and, optionally, an existing-ground surface; Excavation does the same for a DIG™ dig (Excavation with LandXML).

• Coordinates: NAD83 State Plane and UTM are recognised; other systems are read from the file's own WKT if it has one. Check the CRS reading after loading: Unknown CRS or a stretched 3D preview means it wasn't recognised. NAD27 zones that need a grid shift (including the Dakotas) are not supported.
• Units: metres, international feet and US survey feet, as declared in the file.
• Several surfaces in one file: each step shows a dropdown. Pick finished grade for the design, existing ground for the terrain.
• No benchmark: LandXML carries none. Calibrate on the loaded design at an undisturbed zero cut/fill spot.
• The LandXML picker only lets you choose .xml files.

Line designs and surveys (Ditching, Excavation, Tiling)

In Load, each tab has a small import link at the top right. The file uses the same XYZ / XYZP text layout as above, in route order (first line = start of the run).

• Import survey file (XYZ / XYZP) on the Surveys tab takes latitude, longitude and the first elevation as a surveyed route, saves it, and opens the workflow's designer on it, the same as tapping a saved survey.
• Import design file (XYZP) on the Designs tab takes the 4th column as the design line and opens it in the designer as a Freeform line so you can check it before you implement. A 3-column file picked here is imported as a survey.
• Design import works in Ditching, Excavation and Tiling only. Anywhere else: File import is not available for this workflow. Use Ditching, Excavation or Tiling.

Point files and GeoTIFFs for contours

Contour Tiling, Contour-Guided Terracing and Levee draw contours from a field surface. Besides a saved LiDAR DEM or a field you drive, you can bring your own elevation data.

Point file

Any delimited text of ground points (.xyz, .txt, .csv, .tsv). Tap Point File in the field surface window and pick the file (Pick the file on the tablet). A window called Import Point File then shows the first five lines of the file. The app guesses how the columns are split and which is which; check them against those lines.

GeoTIFF DEM

• A single-band elevation GeoTIFF (.tif) of the field, from a LiDAR provider, drone survey or mapping software.
• Contour Settings then shows Source units: Meters / Feet (picture below). It starts on Feet when the app is in feet; most DEMs are in metres, so tap the right one before you tap Generate. The elevation range and line estimate at the top don't change when you switch; only the contours do.
• Up to 64 MB and 4,000,000 cells. Bigger: This DEM is too large to load (…). Clip or downsample the DEM to the field boundary and try again.
• Not a GeoTIFF, or unreadable: Could not parse GeoTIFF file. No elevations inside: GeoTIFF has no valid elevation data.

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How these fit into the contour flow: Contour Tiling: get a field surface and Levee elevation data.

Import errors and what they mean

Some of these appear inside Import failed: …. More causes and checks: Land Forming problems and File problems.

Where imported files end up

The app reads the file from where you picked it. Keep the original design file on the tablet until the job is finished, so you can load it again if you need to. Imported line surveys and designs are saved into the app's own Documents/DitchAssist/surveys and designs folders. More: Files on the tablet.