CoMapeo Area Calculator

Client-side GeoJSON area calculator for comparing multiple point-to-coverage methods in the browser.

This app is designed for loading point GeoJSON, adjusting spatial rules, comparing generated coverage polygons on a map, and exporting the resulting GeoJSON layers.

Quick Start

bun i
bun run dev

Then open the local Vite URL, load a point GeoJSON file, pick or adjust a profile, and run the calculations.

Features

• Loads GeoJSON Point and MultiPoint inputs and normalizes them into point features.
• Compares multiple coverage methods from the same dataset and parameter set.
• Runs heavy calculations in a Web Worker so the UI can keep updating incrementally.
• Previews generated geometries on a Leaflet map and exports each method as GeoJSON.
• Supports built-in and saved parameter profiles.
• Publishes cleanly to GitHub Pages.

Usage

1. Upload a GeoJSON file containing point features.
2. Choose a built-in profile or adjust the calculation parameters manually.
3. Click Calculate all methods.
4. Inspect each result on the map.
5. Switch the displayed area unit between ha, m², and km².
6. Export any generated result as GeoJSON.

Calculation Methods

The app currently calculates these output layers:

• Observed footprint
• Connectivity A
• Connectivity B
• Cluster + concave hull
• Occupied grid

Each method uses the currently selected profile values from the sidebar.

Development

Requirements

• Bun

Commands

# install dependencies
bun i

# start local dev server
bun run dev

# create a production build
bun run build

# preview the production build locally
bun run preview

Project Structure

src/
  main.js                UI, map rendering, profile management, worker messaging
  calculator.js          Shared spatial calculation logic
  calculation-worker.js  Background calculation orchestration
  config.js              Default parameters and built-in presets
  styles.css             Layout and visual styling

Architecture Notes

• The app is fully client-side.
• Long-running geospatial work is executed in src/calculation-worker.js.
• Shared spatial logic lives in src/calculator.js.
• The map preview uses lighter preview geometry where available, while exports preserve the full generated GeoJSON.

Input Expectations

• Input should be valid GeoJSON.
• The app currently expects Point or MultiPoint geometry.
• Non-point geometries are ignored during extraction.

Deployment

GitHub Pages deployment is configured in .github/workflows/deploy-pages.yml.

On pushes to main, the workflow:

• installs dependencies with Bun
• builds the app with Vite
• publishes the dist/ output to GitHub Pages

The Vite config uses a relative base path so the built app works both on GitHub Pages subpaths and when served from the site root.

Contributing

Keep changes incremental and preserve the current product shape:

• upload point GeoJSON
• adjust parameters
• compare methods
• preview geometry
• export GeoJSON

Before opening a PR:

bun run build

If calculation behavior changes, verify at least one real GeoJSON upload in the browser.

License

TODO: add project license.