Collecting resources for MapKnitterExporter.js

[jywarren]

We are exploring parallel tracks for cloud-based MapKnitter exporting, and one option is a JavaScript based process. The base idea is to use Image Sequencer, possibly webgl-distort, and to run in Google Cloud.

A more traditional Ruby/ImageMagick/GDAL approach is being explored here: https://github.com/publiclab/mapknitter/issues/258

Basic version would output a combined JPG image at a given scale or pixel size. Advanced versions might cut tiles or output GeoTiffs.

Code to be moved off-app

• https://github.com/publiclab/mapknitter/blob/main/app/models/warpable.rb#L153-L336
  • generate_perspectival_distort
• https://github.com/publiclab/mapknitter/blob/main/app/models/map.rb#L231
  • run_export, distort_warpables, generate_composite_tiff, generate_tiles, generate_jpg

Resources

• https://github.com/geotiffjs/geotiff.js/#writing-geotiffs-beta-version - geotiff writing in JS
• https://github.com/ddohler/gdal-js/tree/develop-js/examples/tile_tiff - cut tiles in JS with transpiled GDAL.js

Non-JS wrappers

• https://www.npmjs.com/package/imagemagick

• https://github.com/naturalatlas/node-gdal - operate GDAL via JS

• https://github.com/geo-data/gdal-docker

• https://github.com/googleapis/google-cloud-ruby

• https://cloud.google.com/ruby/rails/

• https://cloud.google.com/appengine/docs/flexible/ruby/

[jywarren]

@tech4gt starting to collect resources!!!

[tech4GT]

Oh this is great! Also maybe we can schedule a call to discuss this a little more, I still need to wrap my head around it exactly but this looks very promising! :)

[jywarren]

For sure!!!

[jywarren]

OK, updated in #298 with a more fleshed out architecture plan.

[jywarren]

https://serverless.com/blog/api-ruby-serverless-framework/

https://www.serverless-ruby.org/

[tech4GT]

Wow https://npmjs.com/geotiff is seriously amazing work!

[jywarren]

Closing this now in favor of https://github.com/publiclab/image-sequencer-app/