What one sample does
Drawings draw a service consistently: every cold-water pipe in the same colour and line style, every cable run in another. Auto Linear (sample one line) uses that. You drag a short line across one run, and ZeroCount finds every other run drawn in the same style on the sheet, measures each one, reads the pipe sizes written beside them and files the results as ordinary marker groups. Where hand tracing a floor of pipework takes an hour, a sample takes a few seconds.
The sample takes the colour of the ink it found, so the new groups match the drawing rather than a colour picked from a palette.
Before you start
- Set the scale. A sample measures at the drawing scale in force when you take it. See Setting the scale.
- Check the drawing is available. The Auto Takeoff heading in the New Takeoff menu shows a reason underneath when the tools are greyed out: No active file, Still checking this drawing, Rotate the file back to its uploaded orientation first, or Missing paper-size info for this file (legacy upload). A drawing rotated in the app after it was first opened must be rotated back before sampling; a rotation applied before first open is fine.
- On an image or scanned drawing the heading reads Image drawing — first detection takes a few seconds. Nothing else changes.
Taking a sample
Open New Takeoff and, under Auto Takeoff, choose Auto Linear (sample one line) . The drawing dims slightly behind a faint veil, the cursor becomes a crosshair, and the header shows Current Tool: vector linear sample. Marker selection is suspended while the tool is armed.
- 1
Zoom in so the run you want fills a good part of the screen. See Navigating the canvas.
- 2
Press the left mouse button on top of one run and drag a short distance along it. No modifier key is needed. A red line follows the drag.
- 3
Release. The top of the drawing shows Extracting vector data… the first time a drawing is sampled, then Detecting….
- 4
Wait for the result. On a hit, the tool puts itself away and the new groups appear in the sidebar.
A hit creates one Linear group per pipe size found (for example Ø22mm and Ø28mm, plus Unsized for runs with no readable callout) and two Count groups, Sample 1 · Bends and Sample 1 · T-Junctions, holding one small marker per fitting. Every run is one polyline that carries on through its bends and tees. The sidebar's takeoff panel, above the group list, tracks the sample; Pipe sizes and fittings explains the groups in detail.
Sample a stretch of pipe with nothing else touching it, away from labels and crossing services. The app only needs to see the line's style; it does not need the sample to be long.
When the sample misses
If nothing was found under your drag, the tool stays armed, the line is redrawn as a red dashed guide, and the takeoff panel shows No stroked vectors found under the sample line — zoom in and draw directly on top of a linear. Zoom in and drag again, directly on the ink. The guide clears on the next attempt, when you press ESC, when you right-click, or when you switch to another tool.
A drag shorter than a few pixels is treated as an accidental click and ignored.
Image and scanned drawings
Auto Takeoff works on image drawings too, and the drawing type is detected for you. The first sample on a sheet takes a few seconds while the linework is analysed; later samples are quick. If the drawing has AoIs drawn on it, image detection only looks inside them, which is the easiest way to keep a sample from wandering into a title block or a detail. See Areas of interest.
Marks that are not markers
Alongside the groups, the drawing may show small rings where a run rises or drops. These are overlay marks, not markers: they are not counted, priced or exported, and Clear detection overlay in the takeoff panel removes them without touching your measurements. See Tidying takeoff results.
What happens next
- If Search all files in category is on in Preferences, ZeroCount looks for the same service on the other drawings in the category in the background. See Takeoff on other drawings.
- The sizes read from the sheet appear in the Sizes on drawing popover beside the sidebar search box, and as size badges in mask view.
Common issues
The panel shows an error rather than a miss
Drawing data isn't loaded for this file — reopen it and try again. means the sheet was not fully loaded; switch away and back. Vector extraction failed or Image linework extraction failed mean the drawing could not be analysed; try again, and if it persists the drawing may need re-exporting.
The sample found one run instead of the whole service
The style under your drag did not match the rest of the service, which usually means you sampled a label, a leader line or a stretch where two services overlap. Delete the groups and sample a cleaner stretch.
A second sample of the same service created a second set of groups
Each sample creates its own groups. Merge them from the group menu, or delete the older set. See Merging groups.
Next steps
- Auto Detect Linear — sample every coloured line pattern on the drawing in one go.
- Pipe sizes and fittings — the size groups, Bends and T-Junctions a sample creates.
- Takeoff on other drawings — the background search across the rest of the category.
- Tidying takeoff results — clear the overlay and remove junk runs.