When to draw a manual AOI
The auto-detected AOI is usually close, but you'll want to draw your own when:
- Auto-detection missed a working area entirely (common on hand-drawn or noisy scans).
- The auto AOI overlaps the legend or title block.
- You want a tight polygon hugging only the bits you care about, rather than a rectangular bounding box.
- The drawing has two separate working areas and you'd rather have two AOIs than one large one that includes the gap.
Manual AOIs behave identically to auto-detected ones once placed — they're listed in the same panel, locked the same way, deleted the same way. The only difference is how they're created.
How to draw one
- 1
Open the Zones & AOIs dropdown in the sidebar.
- 2
Click the + button in the AOIs section to enter draw mode.
- 3
On the drawing, click at the first corner of your AOI.
- 4
Hold CTRL and click to add each subsequent corner (on macOS use CMD). Each click extends the polygon edge.
- 5
Right-click to close the polygon. The AOI is added to the list as the next
AOI N.
You don't need to be precise — every corner can be nudged afterwards. Get the rough shape, close, then drag the corner handles to refine.
Editing the polygon
Once placed, the AOI shows handles at each corner. You can:
- Drag a corner — moves that point only.
- Drag the middle of an edge — inserts a new corner at that position.
- Drag the whole polygon — moves the entire AOI without changing its shape.
If the AOI is locked, none of these work. Unlock it from the AOIs section first.
Multiple AOIs on one drawing
You can draw as many AOIs as you like. They can overlap or sit separately. The detection pipeline treats them as a union — it scans the area covered by any AOI.
Typical reasons to have several:
- Two separate working areas with a margin or break between them.
- One large drawing where you want to break the search into halves (useful occasionally when the pipeline times out on huge plans).
- Splitting the same drawing into "what's in scope" vs "reference only" regions.
Drawing around an obstruction
If your working drawing has the legend or title block embedded inside the working area, draw a polygon that wraps around the obstruction:
- Click around the outer edge of the working area as normal.
- Don't worry about the obstruction itself for the first pass.
- After closing the polygon, drag a middle-edge handle to add a corner near the obstruction.
- Drag corners around the obstruction so the polygon excludes it.
Alternatively, draw two simpler AOIs around the bits you want to keep — that's often quicker than carving out a hole.
Sanity-check before Submit
Before pressing Submit, eyeball each AOI for:
- Coverage — does it cover everything you want counted?
- Exclusions — does it avoid the legend, title block, and revision history?
- Closed shape — no open polygons. (ZeroCount enforces this on creation, but a corner-edit can make a self-intersecting shape — fix it before submitting.)