Following photo exhibits several prototypes. On left side is my first Poľana prototype assembled with slightly different technique not explained in this blogpost. In the middle is second generation of Poľana and on the right side is Mt. Everest model.
How to Produce the SVG for Paper Cutting
We will not create the paper model by hand but use a bit of programming. The source code below is Ruby.
First, we need to determine the latitude/longitude coordinates of a rectangle:
and the number of “cuts” through the terrain in x (latitude) and y (longitude):
Picture below depicts that we create 24 paper pieces in x-axis (that is latitude). For each paper sheet we will take 80 elevation points in longitudal axis so that shape of each paper is as real as possible.
Now we create a 2–dimensional table called elevations (size 80x24), where x is latitude, y is longitude, and value is elevation in meters. We use mapquestapi.com HTTP API to get the elevation:
Next we convert the elevations from meters to svg points:
Now we are ready to produce the SVG polylines for cutter machine.
SVG polyline is simply a set of [x,y] pairs which will be connected by lines.