Raster processing roadmap

See initial discussion on https://github.com/systemapic/wu/issues/336

Draft list of requirements

• Import rasters
  • raster2pgsql can do this
• Import rasters to a set (with one raster per row)
  • raster2pgsql can do this (-t )
• Do clipping of rasters (clip away ocean, for example, to reduce size), aka a clip function
  • http://postgis.net/docs/RT_ST_Clip.html
• Import clipping mask polygons which will be used to clip areas for calculations on rasters
  • "Import" where ?
• Query data from raster by tile (based on Google Tile Coordinate)
  • Can be done by unioning the intersection between each intersecting tile and the given google tile polygon
• Query data from raster by tile (based on Google Tile Coordinate) with simplification
  • http://postgis.net/docs/RT_ST_Resize.html ?
• Create vector tiles from raster data
  • node-mapnik should be able to do this
• Create vector tiles from a set of rasters (each raster as one layer, will become a timeseries)
  • node-mapnik can do this (the multi-layer part)
• Query avg, min, max on rasters
  • http://postgis.net/docs/RT_ST_SummaryStats.html
• Query avg, min, max on rasters with an arbitrary clipping mask
  • ST_SummaryStats(ST_Clip(...))