How Inkscape SVG differs from plain SVG: inkscape:* and sodipodi:* namespaces, layer:label, guide lines. Maintaining compatibility with Illustrator, CorelDRAW, and web browsers when exporting OSM maps.
Deep guide to Bentley's MicroStation — the AutoCAD competitor for AEC, rail, roads. V7 → V8 history, ecosystem, OpenRoads/OpenRail, how to import OSM from osm2cdr.ru.
Deep guide to HGT — NASA's SRTM elevation tile format. Structure, accuracy, GDAL workflow, how to combine with OSM exports from osm2cdr.ru for topographic maps.
Deep guide to HPGL — Hewlett-Packard's plotter vector language. PA, PD, PU, SP commands; how to send an OSM map to a vintage plotter or cutting plotter via osm2cdr.ru.
Deep guide to GPS Track Maker (.gtm) — Brazilian binary GPS format. History since 1996, tracks and waypoints, how to convert GPX or OSM to GTM for legacy Garmin or Magellan devices.
EMF — Windows 32-bit vector format, the WMF replacement with Bezier curves and transparency. How to use it for printing, Office embedding, and OSM map export.
Deep guide to ESRI ASCII Grid (.asc) — text format for raster elevation data. NCOLS/NROWS header structure, export workflow, how to combine with OSM exports.
Deep guide to AVIF — image format built on the AV1 video codec. History, spec, browser support, how to compress a raster map export from osm2cdr.ru into AVIF and why.
Zarr is a chunked format for N-dimensional arrays: cloud-native HDF5/NetCDF alternative used by Pangeo, CMIP6, NASA ESA with Python/JS/Rust bindings and stable v3 spec (2024).
WKT is the OGC Simple Features + ISO 19125 text representation of geometries: POINT/LINESTRING/POLYGON; backbone of PostGIS/MySQL/Oracle Spatial, WKT 2 for CRS (ISO 19162).
X3D as VRML successor: ISO/IEC 19775, XML/JSON/Classic encodings, X3DOM web viewer, CityGML mapping, OSM export.
WebP since 2010: Google's open raster format built on VP8. Lossy 25-35% smaller than JPEG, lossless 26% smaller than PNG, with alpha and animation support.