A web-based service that converts publicly available HGT files to useful STL files.

###Try it Out! This project is running on a Google Compute Engine server at jthatch.com. It's updated soon after any commit to this repository.

You can also download everything here and start the server with:

node terrainServer.js

It will run at localhost:8080.

A few .HGT files are included, but not the whole set. You can get the rest from the USGS, or I could send you few.

###To-Do List

• Make dataset voids not just a fixed negative value.
• Make models watertight.
  • Fix voids in edges of models
• Increase maximum box size.
• Fill voids in dataset.
• Make the 3 arcsecond resolution available in all sizes.
• Add ability to cross tiles. !!!
• Make Print and Download buttons disappear or defocus when the selection box is moved
• Make the selection box reflect changes in the Lat/Long boxes
• Decide on a maximum file size and/or compression
  • Add a resolution slider
• Add longitude compensation to correct for the distortion caused by the Mercator Projection
• Draw the northern and southern boundaries of the data set
• Normalize model height to remove vertical offset

###Descriptions of Files

• /hgt_files

  • This directory contains some sample HGT files for testing. Included are Mt. Everest; Rockport, Maine; and San Franciso Bay.
  • The whole dataset is 40GB, so only a few files are included.

• elevstl.cpp

  • This is the source code for the part of the program that actually creates the STL files. Accepts command-line arguments

• gmaps-gridlines.js

  • This script provides the gridlines for the map. It is a slightly modified version of a package found here: https://github.com/alexcheng1982/google-maps-gridlines

• terrain2stl.html

  • The HTML source of the website.

• terrainServer.js

  • Node.js server. Takes parameters from the HTML page and passes them to elevstl to create the STL.
  • Also handles client downloading of pages and files.