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AutoCAD Geolocation

Background Imagery Made Easy!

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AutoCAD Geolocation
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Once in a while, there are some really great tools out there that I feel need to be shared with the CAD world at large. The Geolocation tool inside of AutoCAD is one of those tools. It’s not perfect by any means but I have the feeling that it will be pretty amazing in the next release or two of AutoCAD. So what does Geolocation do? Well, it’s pretty simple: it gives you aerial imagery and map data of the existing world right beneath your drawing, without the need for going out to other programs or going through lengthy import processes.

To break it down, AutoCAD (and all of its vertical products, like Civil 3D and Revit) have the native ability to set a geographic location for each drawing file. You use the drawing setup feature of you package to set a map zone and/or coordinate location (such as NJ State Plane) and you will see a red marker appear on your drawing. This is the GeoMarker and it pretty much contains the data about the geo-location within your drawing. Now, a lot of folks over the last few years have turned this marker off with the “geomarkervisibility” command because they think it’s just some annoying Autodesk feature they have no use for. Truth is, I’ve been known to turn the thing off myself, just to keep my screen clear. You’ll need that marker on in order to use the Geolocation tool though, so leave it be for now.

As soon as you apply a map zone, your GeoMarker appears and you can use the Geolocation tool, just by typing GEO at the command line. The program asks you to set a location from Map/File, you want to use the Map option. This brings up a dialog box where you can input an address, lat/long value and a few other variables to locate the area you’re working in. The dialog will zoom into the area you’re drawing lies in and you can zoom in/out to verify using the icons inside the map. Once you find your area, click the “Drop Marker Here” button, and then choose your map zone (if it isn’t already selected) on the bottom of the dialog, along with your time zone and the units of your drawing. Choose the Continue button and you’ll be returned back to your AutoCAD session.

The program will ask you to select a point on screen for the geographic location point. This point will match the marker location you chose in the dialog box. That enables AutoCAD to align the background maps with the graphics inside your plan. Lastly, the program asks you to enter an angle for north orientation. You can either pick the direction on screen, or enter a numeric value. Once you select north, your screen will fill with aerial imagery. How easy is that? Now for the bad news. There are two frustrating problems here (hence the reason I started out saying it will be amazing in the future!) First, the imagery isn’t printable, it only displays on screen for your reference. Second, there is a maximum zoom level you can go down to within the file before the imagery disappears and is replaced by tiles with a camera icon inside. Those are the concerns that hold this back from being one of the most incredible commands in the Autodesk arsenal. I truly hope they fix those soon.

So, what good does this do for you then? Well, imagine that you just want to see what’s going on from an existing site information standpoint. Instead of going back to field photos or survey sketchbooks, you can handle this on screen in a few seconds. I’ve also seen this used as a way to sketch “out of scope” site outlines that don’t really require a whole lot of precision. If all you want to do is roughly locate the buildings across the street from you site, just draw some quick polylines on top of the aerial imagery and you’re in business! Like I said, it’s a good tool, with the potential to be great, but it’s definitely worth looking into if you work in the civil arena.

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