• Implement RFC 75: support for multidimensional arrays in MEM, VRT, netCDF, HDF4, HDF5 and GRIB drivers. Read/write for MEM and netCDF. Read/only for others. Add gdalmdiminfo and gdalmdimtranslate utilities.
• Implement RFC 76: add capability of writing vector drivers in Python
• New GDAL drivers:
  • COG: write-only, for Cloud Optimized GeoTIFF
  • EXR: read/write driver, relying on OpenEXR library
  • ISG: read-only, for geoid models of the International Service for the Geoid
  • RDB: read-only, for RIEGL Database .mpx RDB 2 files (#1538) (needs proprietary SDK)
• New OGR drivers:
  • FlatGeoBuf: read-support and creation (#1742)
  • MapML: read/write driver for experimental web spec
• Improved drivers:

• OAPIF driver (renamed from WFS3): updated to OGC API - Features 1.0 core spec
• GTiff: improve performance of internal overview creation
• GTiff: GeoTIFF 1.1 support
• Shapefile driver: add read/creation/update support for .shz and .shp.zip
• netCDF vector: read/write support for CF-1.8 Encoded Geometries (#1287)
• VICAR: multiple improvements and write support (#1855)
• DDS: add read support

• Other improvements:
  • gdalwarp: accept output drivers with only CreateCopy() capabilities
  • gdal_viewshed: new utility for viewshed algorithm
• Remove GFT driver now that the online service no longer exists (#2050)
• New Sphinx-based documentation
• Multiple security related fixes (ossfuzz)
• Continued code linting (cppcheck, CoverityScan, etc.)
• Compatibility with GDAL 3.0:
  • C and C++ API: backward compatible changes
  • C ABI: backward compatible changes
  • C++ ABI: modified
  • Functional changes: see MIGRATION_GUIDE.TXT