Note: This methodology is only intended for presentation purposes of your drawings. Following this procedure does not guarantee the high levels of accuracy normally required in related projects.
In most cases AutoCAD projects are based on a specific coordinate system, which the user can select from Plex.Earth's lists before performing any function. But what if you have a drawing that is not georeferenced (could be created around (0,0) or at any arbitrary coordinates), is there a still a way to import images or publish elements to Google Earth?
Yes, if you follow these simple steps:
Step 1: Set Google Earth to UTM
Open a Google Earth window and go to Tools -> Options. In the window that will appear select to show Lat/Long in the "Universal Transverse Mercator" format as shown in the image above.
Step 2: Define which UTM Zone the area of your project belongs to
Manually zoom Google Earth into the area of your project. The first two numbers that appear in the coordinate bar define the applicable UTM Zone. You can then click on Plex.Earth's "Select Zone & Units" and choose "Earth" as the region and the appropriate WGS84 UTM Zone as the Coordinate System. In the example above we will select WGS84 UTM Zone 32N ("N" stands for North Hemisphere, and "S" for South Hemisphere respectively).
Note that any other applicable coordinate system can also be selected. If, however, you are unsure which systems can be used for the specific area, WGS84 is the safest choice.
Step 3: Import a georeferenced image
Now manually zoom Google Earth into the exact area of your project and use Plex.Earth's "Import Image from Current View" command. This will import the image in its correct coordinates (in WGS84 or any other coordinate system you have selected). You now have the following two options:
Option 1 (recommended): Set a permanent displacement in Plex.Earth
If you do not want to make any alterations to your project, you can now open Plex.Earth's "Options" and define a standard displacement. All subsequent Plex.Earth functions will make use of this displacement and will shift the imported elements accordingly. If, therefore, you use "Import Image from Current View" again, the image will now be imported where your project lies and you may now bring in more images and data points to create contours and surfaces directly at the location of your project. Note that depending on the orientation of your drawing, you might need to rotate the imported elements for them to align correctly with your existing objects.
Option 2: Move your project over the image
Alternatively, you can move your project on its actual location on the imported image, scaling and rotating it as needed. Your drawing will now be roughly georeferenced and you can use any Plex.Earth function to import more images, fetch terrain data and create surfaces and contours, or export your project to Google Earth as you would do with any other drawing.
Warning: This option can lead to serious issues with your drawing (in the case, for example, of dynamic references)and can also alter the dimensions of your elements, so should be used cautiously.
Do you have any questions or need further clarifications? Contact us at firstname.lastname@example.org