Lens User Guide & Data Reference
Interactive choropleth mapping, demographic analytics, and GeoJSON boundary export for Philippine administrative divisions.
The Problem Lens Solves
Before Lens, performing spatial analysis or visualizing socio-economic metrics across Philippine municipalities required downloading heavy GIS desktop software (such as QGIS or ArcGIS), searching through disparate government portals for boundary shapefiles, converting legacy coordinate projections (e.g. PRS92 / Luzon 1911 to WGS 84), and manually matching spreadsheet rows to spatial features.
Lens eliminates this friction by serving pre-processed, PSGC-indexed vector boundaries directly in the browser. Anyone—from data journalists and urban planning students to software engineers—can instantly visualize demographic trends, compare municipal indicators side-by-side, or export clean GeoJSON files for custom application development.
How Lens Works at a Glance
Loads optimized GeoJSON and TopoJSON boundary layers dynamically as you pan and zoom, rendering crisp vector outlines at 60 FPS without server-side map tiling bottlenecks.
Joins public census, financial audit, and election data tables directly to spatial boundary polygons using standardized 9-digit PSGC numeric keys.
Exports boundary polygons in RFC 7946 GeoJSON format (WGS 84 coordinate system), ready for instant drop-in use in Mapbox, Leaflet, Turf.js, or PostGIS.
First-Time Visitor Walkthrough & Key Features
A. Navigating Administrative Tiers
Use the administrative level selector in the top toolbar to switch between Regional, Provincial / HUC, Municipal / City, and Barangay boundary layers. Hovering over any polygon highlights its official name, PSGC code, and summary metric card.
B. Toggling Demographic & Civic Data Overlays
Lens includes several pre-loaded dataset layers compiled from official Philippine public reports:
- Population & Density (PSA 2020 CPH): Total headcounts, population density per sq km, and age/gender pyramids per municipality.
- Gross Domestic Product (PSA Provincial Accounts): GDP contributions formatted in constant 2018 prices.
- LGU Assets & Revenues (COA Financial Audit Reports): Annual municipal revenue, liabilities, and equity balances.
- 2022 Presidential Election Tallies (COMELEC): Aggregated municipal vote breakdowns and turnout statistics.
C. Custom CSV Spreadsheet Uploads
To visualize your own data, upload a CSV spreadsheet containing a psgc column (e.g. psgc,value). Lens automatically parses the codes, normalizes the numeric values into a color gradient choropleth, and renders your dataset on the interactive map canvas.
D. Comparing Administrative Units Side-by-Side
Click the Compare button and select any two provinces or cities. Lens splits the viewport to display side-by-side demographic comparisons, financial balance sheets, and geographic footprint overlays.
E. Exporting Clean GeoJSON Boundary Files
Select any province or municipality and click Export GeoJSON to download a clean, validated .geojson file containing polygon coordinates, bounding box metrics, and PSGC metadata properties.
Data Sources, Accuracy & Edge Cases
All demographic metrics in Lens are derived from public datasets published by the Philippine Statistics Authority (PSA), the Commission on Elections (COMELEC), and the Commission on Audit (COA).
• Recent Administrative Reclassifications: Newly created LGUs (such as Carmona City converted in 2023, or the 8 new SGA municipalities in BARMM established in 2024) are continuously reconciled as official PSA PSGC releases are updated.
• Boundary Simplification: Cartographic polygons undergo Douglas-Peucker simplification to maintain high render performance on mobile devices. For high-precision legal cadastral surveying, consult official NAMRIA map sheets.
• Non-Government Disclaimer: Lens is an independent civic tech tool and is not affiliated with or endorsed by PSA, COMELEC, or any government agency.