Generating the contours

Once the boundary is settled, the contour settings dialog opens. This is where you choose how far apart the contours are.

Contour interval

The interval is the elevation difference between one contour and the next. A 6-inch interval draws a contour every 6 inches of elevation change; a smaller interval draws more lines, closer together. Pick from the preset buttons (in inches, or millimeters on metric) or type your own value. The dialog shows an estimate of how many contour lines that interval will produce — if it warns the count is very high, increase the interval.

Source units (GeoTIFF and point files only)

If the app cannot tell whether the file's elevations are in meters or feet, a Source units choice appears. Pick the one that matches your file so the interval and contours come out at the right spacing. Surveys you drove and LiDAR downloads are always handled correctly, so this choice is hidden for them.

Smoothing

The smoothing slider has 9 stops: None / Minimal / Light / Med-Light / Medium / Med-Heavy / Heavy / Very Heavy / Max. Default is Medium. Higher values evens out roughness but can lose fine detail; lower preserves detail but may carve jagged contours from noisy data.

Tap Generate

The app first builds the elevation surface — you'll see "Generating elevation surface" while it fills in the area between your data points — then it traces the contours and draws them on the map, colored by elevation (blue for lower, red for higher). For big fields or dense data this can take a little time; let it finish.

When the contours appear, the app auto-saves the job so you can come back to it. From here, pick a contour and drive.