Pune Development Plan
To overlay multiple static maps like Development Plan maps over a pan-and-zoom web map
Development Plan and similar maps are typically released as PDF exports or images, lacking any geolocation data of their own. For the public to inspect these maps, it is difficult to do so out of context, ie, in the absence of an actual present-day map with which to compare. This project aims to solve that problem.
There is a website called <mapwarper.net>. We can upload a map image and 'pin' it to a web map. It then 'warps' the image to fit the web map. After this, the website publishes this warped map as a map tiles source, similar to how google or OSM or Mapox publish their maps.
Nikhil has created this script : overlap.html which overlays these warped maps on top of a normal map layer. There is an opacity fader to fade in or fade out the overlay. Change the dropdown to see the older development plan maps.
So the tool is ready; now the maps need to be warped.
They are in PDF form, and have been converted to high-resolution images and loaded up on mapwarper
- Go on mapwarper.net and sign up to create a free account for yourself. Stay signed in.
- Keep this guide open in another tab: http://datameet.org/2016/08/12/guide-on-digitizing-static-maps/. Skip ahead to section 3.1 (“Map Warping : Get set”)
- Open this tracking sheet and scroll to bottom or hit Ctrl+F and search for “PuneDPmar17”: https://docs.google.com/spreadsheets/d/1WpqOvcYeYtnkDdFDyyn56jlxSwSVkxNz8XmPRtLepKU/edit?usp=sharing
- Pick a map, click the link to open. Follow the instructions in the guide opened earlier and warp it.
- Go just till section 3.3 (“Map Warping : Preview and Export”) and then contact me (Nikhil) on nikhil.js (@) gmail.com . I’ll add you to the spreadsheet so you can mark which map is done.
- If you’re feeling good then go back to the spreadsheet and pick another map to warp.
- Once we’re done, we’ll load them up on this page: https://answerquest.github.io/overlap.html. The spreadsheet has a formula in one of the columns to generate HTML code for populating the dropdown with the new maps.