DEMs

[kj6tk]

The 3D is great, but the few DEMs for my area don't cover the areas I run with my Forerunner. Is there another source of DEMs that may have more of SoCal. I downloaded all the (free) DEMs for OC from http://data.geocomm.com/dem/demdownload.html

and it only has a few spots with DEMs. The areas with DEMs work great in TopoFusion 3D. And yes it is a long process to load them but once you have them in the DEM directroy its as simple as pushing the 3D icon, The aerial images look great in 3D. I just wish that I had some DEMs for the areas I run and map.

Big John

[Krein]

Tom Harvey posted a link to this site:

http://130.166.124.2/dems.html

Which has DEMs for most western states.  You need to know the name of the DEM that you want though, unfortunately.

There are other sources (click below in the forums to change it so you are viewing ALL topics, instead of only those in the last 30 days, which is the default).

[Alan]

Yes, the NED is probably the easiest, you can select a large area and you don't have to know the quad names.  It's a bit complex, someone (like myself) will have to post a tutorial on how to get them and convert them to the appropriate format.

[BVH]

I downloaded a Burbank CA DEM from the Northridge University site. (http://130.166.124.2/ca_dems.2/)  It saved with a .DEM extension but shows as a GZ file.  I loaded it into the default TopoFusion directory and tried to see a 3-D view of a short walk in burbank but nothing happens.  Does this file need to be converted or?

Bob

[Alan]

I get "File Not Found" at http://130.166.124.2/ca_dems.2/

But if it a .gz file that is gzip.  You can use winzip and many other archiving programs to un-gzip it.

[BVH]

Alan, thank you.  I unzipped and copied it to the Topofusion folder and 3-D now works.  Talk about eye candy!  Its pretty cool to be able to rotate the image!  Each end of my route extended into an area that did not get "3-D'd".  When I chose the particular file to download, it was represented as having an an area much larger than my route.   Do I assume that the DEM data file contained data that extended only to the portions of the route that showed in 3-D?  Also, I'm wondering how to display the solid elevation colors of the terrain as shown in the first few screenshots of the first post in the forum topic "3-D coming soon".  I have tried all the toggles and am wondering if that, too, is a function of DEM data file?

This program is truly a magnificent product!!

Bob

[Alan]

Regarding the extent of the DEM, while in 3d mode, try zooming out and pressing 'r' to regenerate the model.  At some point you will see the full extent.  When you go into 3d mode, it attempts to view exactly what you're currently viewing in 2d.  So most of the time it will just be a part of the DEM(s).

Regarding the color-by-elevation, that's not in the current beta.  We didn't realize that people might be interested in it.  You can get shaded white by turning off the maps (one of the toolbar buttons).  Is the color-by-elevation of the DEM model something you'd like to see in future versions?

[BVH]

Alan, I tried zooming and regen'ing.  All tiles in the view are now displayed but only the one original tile displays in true 3-D.  adjoining tiles have no depth.  if i rotate the view, it is as if im looking at a flat earth -there's a 1000 foot sheer drop down to the other tiles.  part of my route is actually on the non-3-d tile in addition to most of it being on the 3-d tile.

Bob

[Alan]

Sounds like you're seeing the extent of the DEM.  You need more DEMs.  The easiest way to get them is to follow the documentation (in progress) at http://www.topofusion.com/3d.php#acquire to get a much larger area from the USGS.