Data sources and attribution
What comes from a provider, what is calculated in SunCarta and what remains under your control.
Last reviewed August 8, 2026Source register
Base map
Provider: OpenFreeMap, using an OpenMapTiles-compatible style and data attributed to OpenStreetMap contributors.
Use: global geographic context. A visible footprint is never silently treated as a height-verified building.
Address search
Contract: a Photon-compatible GeoJSON geocoder based on OpenStreetMap place data. The browser calls SunCarta’s same-origin `/api/geocode` Pages Function rather than contacting the configured provider directly.
Processing: the Function bounds query length and result count, validates language, sanitizes returned fields and caches repeated normalized queries at the edge. Responses sent to the browser are marked not to be stored by browser or intermediary caches. The low-volume canary can use the public komoot Photon endpoint; production should use a managed or self-hosted compatible endpoint.
Fallbacks: latitude and longitude entry, browser geolocation and direct map placement remain available when search is unavailable.
Time zones
Source: an offline geographic lookup returning an identifier from the IANA Time Zone Database.
Use: applies local civil-time offsets, including applicable daylight-saving rules, to the chosen date.
Solar calculation reference
Reference: NOAA Global Monitoring Laboratory.
Use: equation-of-time, declination, hour-angle, sunrise, sunset, altitude and azimuth calculations implemented locally in the browser.
Obstacle and room geometry
Source: values the visitor adds or edits in the active project.
Use: receiving point, direction, building, wall, tree and window dimensions. These values stay in browser storage by default and are never presented as provider-verified facts.
Attribution in the product
The interactive map retains its required attribution control. Source links remain visible here even if an implementation provider changes. SunCarta’s original outputs are calculated solar positions, simplified shadow projections, obstruction checks, direct-sun samples, indoor reach estimates and the explanations around them; source map records are not republished as a new raw database.
Coverage upgrades require provenance
Future releases may add open building footprints or height fields. Such features are eligible only with visible source provenance, geographic coverage checks, age or version information and a user correction path. Missing height remains unknown, never zero by implication.