Scafell Pike 3D pdf.
If you have Acrobat Reader 7 or later installed then the object below should display a 3D PDF of Scafell Pike (431 KB).
A 3D pdf showing my favourite Lake District walk up Scafell Pike, England's highest mountain. The model shows animated markers which locate my position every minute, the colour of the markers shows my heart rate: 100 bpm on the easy bits, rising to 170 bpm on the steep bits uphill and scary bits downhill. The data was recorded in 2002, but I had to wait 6 years until I had the wherewithal to make it presentable!
I got the elevation data for the model of Scafell Pike from NASA's Shuttle Radar Topography Mission, from file N54W004.HGT, this data is freely available. I reprojected the elevation data into National Grid coordinates using the Jo Wood's excellent LandSerf program. I then manipulated the appropriate region in an Excel 2007 file (2007 required as the area of interest spanned 300 columns!), and used excel to produce an IDTF "intermediate data text file" for processing by IDTFConverter. As U3D surfaces only have triangular and not rectangular elements I chose to create a triangular mesh, by interpolating the heights every 50m, and shifting the eastings back and forth by 50m for every 100m north, keeping a triangle side of about 100m. I coloured the elements by elevation, the colour was inspired by a map in Edward Tufte's Visual Explanations. I considered mapping an aerial photo onto the surface, however I couldn't find a way to project images onto existing surfaces in a 3D pdf, either in the U3D model or by javascript in the pdf, and as there are no freely reproducable aerial photos of England that I could use for the projection, it was a moot point. An aerial photo would have also added clutter and distracted from the location markers.
I logged my location with a Garmin GPS 12, which I bought cheaply when it was discontinued in 2001! I logged my heart rate with a Ciclosport HAC4 heart rate monitor.
The elevation of the markers in the model was interpolated from the GPS location rather than using the height from the hrm's barometer, with some trickery in the excel spreadsheet. I found that the barometer was sensitive to the weather conditions over the course of the day, which lead to the markers being above and below the surface!
The U3D model which is the 3D part of the pdf was created with a modified version of IDTFConverter, I modified this to set the quality to 100%, and apply the same quantisation to the nodes for both lines and surfaces such that lines and surfaces remain aligned in the U3D file.
The embedded pdf was created with pdflatex, part of the MiKTeX suite, using the movie15 package.