http://tangrams.github.io/heightmapper

Heightmapper is an interactive grayscale heightmap browser, which can generate heightmaps for use in 3D applications. By default, it "auto-exposes" the display so that the highest visible elevation in the current view will be white, and the lowest will be black.

Uses Mapzen's global elevation service.

• Uncheck "auto-expose" to set min and max height levels manually.
• Check "show lines" and "show labels" to see more map data.
• Click "export" to open the current view as an image in a new tab - "Save As" to save the image to disk.
• Import the resulting image as a "displacement map" in a 3D application to generate a 3D model of the terrain. (Here's a tutorial for doing this in Blender.)
• The "z:x scale factor" describes how "high" the current view is, on the z-axis, in terms of how wide the current view is on the x-axis. Multiplying this scale factor by the width of a 3D mesh in units x will tell you how high in units z your mesh should be after displacement in order to be true-scale.
• Press the "h" key to toggle UI visibility.

• Render Multiplier (1 - 8) will split the view up into that number of cells on the x and y axis. i.e., a Render Multiplier of 4 will render a 4x4 grid.
• Render Name is the name of the output file you want.
• render will automatically zoom to each area and stitch together a high quality render, then save the render as {render name}.png to your downloads.

This comes with a gotcha: the map must take up the entire view (no whitespace above or below) for the renderer to work properly.

Do not resize the view or move the map during render as this will interfere with the render process.

• add a GeoTIFF export option which includes metadata
• fix Render Multiplier issue when the view bounds exceeds the tile latitude limit.
• Super Extra Credit: further export options including lat/lon bounding boxes, country/boundary masking using OSM vector tiles

Start a web server in the repo's directory:

python -m SimpleHTTPServer 8000

If that doesn't work, try:

python -m http.server 8000

If running this produces CORS errors on your local machine, try:

python run-server.py

or

python3 run-server.py (on mac)

Then navigate to: http://localhost:8000