PlotMeasure Pro is a native macOS app for measuring plot and land area from cadastral, survey, and revisional map PDFs. It uses SwiftUI and PDFKit, stores geometry in PDF page coordinates, supports scale calibration, and exports annotated reports for land-measurement workflows.
- Latest release: v1.0.0
- Package asset:
PlotMeasure-Pro-v1.0.0.zip - Target platform: macOS 13+
- Download
PlotMeasure-Pro-v1.0.0.zipfrom the releases page. - Extract
Plot Measure Pro.app. - Move it to
/Applicationsif you want a standard install. - Open the app.
Current release note:
- this build is ad hoc signed, not Developer ID notarized
- macOS Gatekeeper may ask you to confirm opening it on first launch
- Open scanned or vector cadastral, survey, and revisional map PDFs
- Calibrate by manual distance,
1:Nratio, map scale, or visible scale bar - Measure distance, path length, polygon perimeter, and polygon area
- Store points in native PDF coordinates so zoom and pan do not affect accuracy
- Edit vertices by drag, insert, delete, and numeric coordinate update
- Export JSON, CSV, and annotated PDF outputs
- Show results in
sq ft,sq m,acre,hectare,decimal,bigha,kattha, anddhur - Support OCR-assisted scale suggestions and edge snapping for scanned maps
- Native macOS UI with sidebar, PDF canvas, inspector, toolbar, and status bar
- PDF import, page navigation, page rotation, zoom, and pan
- Multiple calibration workflows
- Distance, path, and polygon measurement
- Polygon validity warning, centroid, and live overlay rendering
- Vertex editing with undo and redo
- OCR-assisted scale detection
- Edge snapping support
- Project save and load as JSON
- Annotated PDF, CSV, and JSON export
Supported map types:
- cadastral maps
- survey maps
- revisional maps
- scanned map PDFs
- vector map PDFs
Calibration modes:
- manual two-point calibration
1:Nratio calibration- map scale entry such as
16 inches = 1 mile - scale-bar calibration from visible map conversion bars
- Example project: Examples/sample-project.plotmeasure.json
- Example notes: Examples/README.md
PlotMeasurePro/
├── .github/
│ └── ISSUE_TEMPLATE/
├── CHANGELOG.md
├── Examples/
├── LICENSE
├── Package.swift
├── README.md
├── Docs/
│ ├── plotmeasure-pro-preview.svg
│ └── Screenshots/
├── Scripts/
│ └── package_app.sh
├── Sources/PlotMeasurePro/
│ ├── App/
│ ├── Models/
│ ├── Services/
│ ├── Utilities/
│ └── Views/
└── Tests/PlotMeasureProTests/
└── GeometryAndCalibrationTests.swift
- Open
Package.swiftin Xcode 16 or newer. - Select the
PlotMeasureProexecutable scheme. - Run on macOS.
The local sandbox in this environment requires --disable-sandbox for SwiftPM. On a normal local machine you usually do not need that flag.
cd PlotMeasurePro
SWIFT_MODULECACHE_PATH=/tmp/plotmeasure-module-cache \
CLANG_MODULE_CACHE_PATH=/tmp/plotmeasure-module-cache \
swift build --disable-sandbox --scratch-path /tmp/plotmeasure-scratch
swift run --disable-sandbox PlotMeasureProcd PlotMeasurePro
SWIFT_MODULECACHE_PATH=/tmp/plotmeasure-module-cache \
CLANG_MODULE_CACHE_PATH=/tmp/plotmeasure-module-cache \
swift test --disable-sandbox --scratch-path /tmp/plotmeasure-test-scratchcd PlotMeasurePro
./Scripts/package_app.shThis generates:
dist/Plot Measure Pro.appdist/PlotMeasure-Pro-v1.0.0.zip
The app stores every clicked vertex in native PDF page coordinates, not screen coordinates. Zooming and panning never change the actual measurement geometry.
- Click two known points on the map or printed scale bar.
- Enter the real-world distance and unit.
- The app computes:
metersPerPDFPoint = realWorldMeters / pdfCoordinateDistance
Every later segment length becomes:
realWorldMeters = pdfDistance * metersPerPDFPoint
Polygon area becomes:
realWorldAreaSqM = pdfArea * (metersPerPDFPoint ^ 2)
PDF pages use printer points, where 72 PDF points = 1 inch on the page. For a true 1:N map:
metersPerPDFPoint = (0.0254 / 72) * N
This is best when the PDF reflects the printed scale accurately. For scanned maps, manual calibration is often more reliable.
The app converts both paper distance and ground distance to meters, derives the ratio, and applies the same 1:N formula internally.
- Calibration accuracy depends on scan quality and the reliability of the printed scale.
- Local land-unit standards can vary by district or state, so regional unit settings may need adjustment.
- Current release is packaged for macOS only.
- GIS export formats such as GeoJSON or shapefile are not included in
v1.0.0. - This public repo does not bundle any real survey or cadastral source PDFs.
- Cache page edge maps per page and invalidate only on rotation or document change.
- Add thumbnail or raster caches for OCR and snap assists rather than re-rendering on every request.
- Move OCR and edge-map generation onto detached background tasks with cancellation.
- For very dense polygons, cache measurement analysis until points change.
- For very large documents, keep only the active page overlay data resident and lazy-load the rest.
For distribution beyond local testing:
- Sign the app:
codesign --force --deep --sign "Developer ID Application: YOUR NAME" "dist/Plot Measure Pro.app"- Verify the signature:
codesign --verify --deep --strict --verbose=2 "dist/Plot Measure Pro.app"
spctl --assess --type execute --verbose "dist/Plot Measure Pro.app"- Notarize with
notarytool, then staple the ticket.
- Assisted boundary tracing from detected edges
- Loupe or magnifier around the pointer
- Multi-plot comparison workflows
- GIS export formats such as GeoJSON and shapefile handoff
- Optional OpenCV integration for stronger edge and contour extraction
- Richer project library and batch reporting