So, yesterday I wrote the story about the new time gadget. I wanted to take a GPS track in mountainous areas and show it with the new time animation. As I thought about the process, I was wishing my favorite GPS tool GPSVisualizer.com supported the new time stamp features of KML for GE. So, I sent an E-mail to the author of GPSVisualizer. Three hours later I get an E-mail back from him “Done!”. Now that’s good hacking! It turns out he couldn’t even test it because the Mac version is was not yet supporting the time gadget properly. (NOTE: Updated Mac version now works – see this). But, it worked anyway. Amazing!
Last spring I wrote about a GPS track I made while skiing Snowbird in Utah. I used GPSVisualizer’s handy newly updated GE form (instructions below) to upload and timestamp my track. You can load the resulting new GE file for the ski trip
, and if you are using the new GE 4 beta (Windows version 4.0.2080+, or Mac 4.0.2093+) you will see the time gadget appear in the upper right (left of the nav gadget). I recommend you select a small range of the data (grab the little handles and make the range small). Then, here is the really cool part: push the “Play” button on the far right of the time gadget. It will animate through the track of my skiing and riding up the lifts. You will even see when I paused for lunch at the restaurant mid-mountain. The data loops automatically. If you click the “clock” gadget on the left side you can set the animation speed slower (although even at slowest it is still fast). Try moving your view while it is animating. Very cool!
To use GPSVisualizer to make your own time stamped GPS track, here are the minimum steps (you have lots of other choices on the form).
- Go to the GE Form of GPSVisualizer
- Browse to the GPS file you want to upload (GPX is preferred)
- Choose “Colorize by:” either altitude, or speed preferred. Or, alternatively choose the “Track options:” as “Draw as waypoints“.
- Choose “Add time stamps, if possible” to “Yes”
- You can now “Create KML”
After a pause, as it generates your file you will get a link to your KML file. Load that in GE and you should see the time gadget appear. Very nice work by Adam at GPSVisualizer!
About Frank Taylor
Frank Taylor started the Google Earth Blog in July, 2005 shortly after Google Earth was first released. He has worked with 3D computer graphics and VR for many years and was very impressed with this exciting product. Frank completed a 5.5 year circumnavigation of the earth by sailboat in June 2015 which you can read about at Tahina Expedition, and is a licensed pilot, backpacker, diver, and photographer.
Just to clarify: the reason you must colorize by some field, or draw the track as if it were waypoints, is that otherwise tracks are drawn as continuous lines whose points are defined only by latitude, longitude, and elevation; you can’t add time information to each vertex of a polyline.
When you colorize, however, the track must be broken into numerous tiny segments, and each of those can have its own timestamp assigned. Similarly, if you add a “waypoint” to each trackpoint, those points can obviously receive timestamps. The advantage of the latter approach is that you can see the full path, drawn as a thin line, AND the fatter points that animate as time passes.
Of course, you can also colorize AND draw the track as waypoints; in that case, the little circles inherit the color of the trackpoints that spawned them.
Is there a reason nothing happens when i click play?
Great stuff, thanks for introducing me to this pairing of the GE Time-Slider and Adam Schneider’s excellent GPS Visualizer. (The ‘Schneider-Slider Combination’?)
1) Is it possible to get just one marker/icon tracing the track? So far the best I’ve managed is a short cluster, by reducing the gap between flags to a minimum. (If I try dragging it any smaller, it ‘snaps’ closed completely, giving no marker at all.) That would be just fine for a ramblers group, but not my solo walks!
2) When I first load the GPSV KLM file into GE and play the time-slider, I see the default colours, or whatever I chose in the GPSV form. For the moving icon/marker I like that small solid circle, and would like to keep it. But if I try to customise the track in GE, I lose that icon, and there seems no equivalent option in the choice from GE.
3) For your skiing track, how did you get the result to NOT show the track itself, just the position markers? So far, I am seeing the track too. That’s OK, but for a walk alongside say a plainly visible river I’d like to try just a marker.
4) What options gave you that neat multi-coloured appearance?
Much appreciate any help you can give please.
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Terry Pinnell, West Sussex, UK