Wondering how do I clip images to polygon outlines in a web map application based on OpenLayers or Leaflet? How can I limit web map users to see (visualize; qualitative) or query (quantitative) within the field polygons? E.g. user John has polys 1, 2 and 3 and user Mark has polys 7, 8 and 9. I want to limit John to just his polys and Mark to just his polys. I guess I can clip the images for each user and his polys, but if there are multiple users wanting to access the same images and polys, its redundant to copy the images to multiple users... Is there a programmatic way to limit this? Open source tools are preferred.Source - ClimateCorp FieldView

  • 1
    If the problem is protecting the layers, then you can't achieve that on the client side, since the user could simply open some other application and view the data. What is the server configuration for your web map? Do you have WPS?
    – BradHards
    Jan 4, 2017 at 22:25
  • Thanks Brad, the goal is to restrict the user from seeing/querying anything outside of their area. I'm not very thorough in this topic, but its based on OpenLayers 3x, PostGIS and JS. If the the tool has UI or IAM capability, is it possible to define user spatial extents (irregular polys) based on user account? E.g. restrict Mark to poly within Texas (US)? Jan 4, 2017 at 22:36
  • 2
    Does your OL3 application directly query postgis for the layers? Or is there something else involved like geoserver or mapserver? The architecture matters a lot, so you should edit your question to add this information.
    – BradHards
    Jan 4, 2017 at 22:51


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.