The Perry-Castaneda Library Map Collection at the University of Texas at Austin has begun an ambitious project to scan all available pre-1945 USGS topographic maps for all US states that don’t currently have them available online. They are starting with Texas and working their way out from there. As of today, . . . → Read More: Nationwide Historic USGS Topo Map Scanning Project
I recently finished updating the Google Earth Resources page. This page contains a list of Google Earth related blogs, developer/user tools, etc. that will be of use to the casual Google Earth user and the advanced KML developer. The resources have been organized into various categories, and a short description is provided for . . . → Read More: Google Earth Resources
Looks like a lot of people are using the Google Earth USGS Topographic maps. Couple updates that I thought I’d pass on.
First of all, I recompiled the index to be much easier to use. You no longer have to navigate through two index levels. Now, simply zoom down and the index . . . → Read More: USGS Topographic Map Update
Network Links are a very powerful, but very simple, feature of Google Earth that every Google Earth user should understand. Also, EVERY Google Earth content developer that hosts KML/KMZ files online should understand Network Links and make use of them when it makes sense. So take a couple minutes and read below to learn how to make use of this powerful feature of Google Earth.
Normally when you add custom KML content to you My Places, all of the data included with that custom KML file gets added to your main myplaces.kml file (saved under Documents and Settings\username\Application Data\Google\GoogleEarth\myplaces.kml). For example, if you were to click on this KMZ file link and save the content to your permanent My Places folder in Google Earth, then you would have just made your myplaces.kml file about 15 megabytes larger than it was before and you would notice that it now takes Google Earth several more seconds to start up. Do this 10 or 15 times and your myplaces.kml file can quickly grow out of control. Also, if the original author of that KMZ file updates it, then you would need to go back to their website and download it again to get the update.
If instead, you decide to use a Network Link, some important things will happen:
- Instead of your myplaces.kml file becoming 15 megabytes larger, it will only become 1-2 kilobytes larger. You can add 1,000′s of Network Links without having to worry about the size of your myplaces.kml file.
- If you create a Network Link to a remotely hosted KML file, and the original author of that KML file decides to update it in the future (and doesn’t change the url/filename), then that update will automatically transfer to your machine.
- If you create a Network Link to a KML file stored on your local hard drive, then it won’t affect the size of your myplaces.kml file and won’t affect Google Earth’s load time.
How does all this happen? Simple, because the Network Link does not load the actual KMZ file until you enable the Network Link in Google Earth by checking the box next to it. The table below gives some recommendations on when to use Network Links, and what type of Network Link to use.
Continue reading Google Earth Network Links Explained