Import Aerial and Satellite Imagery along the whole length of your project.
Introduction
This tutorial shows how to import imagery along a corridor in AutoCAD with Plex-Earth 5. This feature can be fully utilized in long construction projects such as roads, bridges, railroads, pipelines, etc.
Usually, when importing imagery by selecting a rectangular area, like for the road project below, Plex-Earth will generate tiles for the whole area, even though many of them might not be useful. For example, it will import 45 tiles in order to cover the totality of the north/southbound road.
However, by following the methods below, for importing imagery along a corridor, the tiles required will be greatly reduced to almost half.
This procedure, which basically imports imagery along a polyline path and its area, is also more time-efficient, as opposed to importing imagery by selecting a rectangular area, because it will prevent unnecessary tiles to be calculated.
This tutorial will present two alternative ways how this can be done.
Note: Make sure your drawing is always georeferenced first before importing imagery.
Case 1: Along the Path of an Axis (Polyline)
This is the fastest and easiest way to import imagery with the least amount of tiles required to import imagery.
Step 1. Defining your Axis
Set an axis (polyline) which will be the basis of the path of the imagery.
It can be the centerline of the project or you may choose an existing polyline.
For this example, we will select the centerline of the road.
Step 2. Importing the Imagery
Click "Import Imagery" on the Imagery Panel of Plex-Earth 5 ribbon and select "Create Imagery Mosaic".
In the command line of AutoCAD, click on "Polyline". Then, select the polyline on the drawing, which is the centerline of the road, and hit enter.
You can click on the "Calculate Mosaic" button, if the provider displayed is the one you prefer, or you may select a different provider instead.
Now, Plex-Earth will display the tiles required. It will only calculate these tiles where their area crosses the polyline itself.
For this example, zoom level 19 was used for good quality and the calculated tiles were 22.
Case 2: By Polyline around Corridor Area
This method can be used if one prefers to import imagery to cover a band with specified width along each side of the axis path.
Step 1. Defining your Axis
Define the axis just like in Step 1 of the previous case. The same centerline will be selected for this case.
Step 2. Creating the Boundaries of the Corridor Area
Use the "offset" command of AutoCAD to create two polylines on each side of the centerline which will be the boundary of the imagery to import.
Click on the centerline and type "O" on the command line and hit enter to trigger the offset command (or click the offset command found on Home > Modify > click on Offset icon).
Specify the width of the corridor for each side by typing it on the command line.
For this example, it is set to 100. Click on either the left or right side of the centerline and create the offset.
Once one side is done, repeat the process on the other one.
Connect the two polylines created, by making another line at the top and bottom of the road.
These two will serve as an upper and lower boundary and will delimit our area.
Select all of the lines and join them by typing "J" on the command line. Hit enter and the lines will be joined into one polyline.
Step 3. Importing the Imagery
You may now proceed with importing the mosaic imagery similar to Step 2 of the previous case, but instead of selecting the centerline polyline, we will select the joined polylines created from the offsets.
This method will require 29 tiles and needs more tiles compared to the previous method however, it can cover certain areas that the previous method could not.
Step 4. Clipping the Imagery
To view the imagery only within the corridor boundary lines and to create a uniform result, the clipping tool of Plex-Earth can be used.
On the Imagery Manager, click on "Edit" and choose "Clipping..."
On the command line, select "Set" and click on the boundary polyline and wait for the clipped imagery to be displayed.
The photo below shows how the clipped imagery would look like when zoomed in on the upper part of the drawing:
Conclusion
Designing is a very demanding process. The engineers many times do not have the luxury to make big imports or create heavy AutoCAD drawings. Large-scale construction projects can be a real struggle actually. However, Plex-Earth offers great freedom on how to handle imagery imports, and with the correct workflow, it can be a real time saver to the designers.
Feel free to contact us at support@plexscape.com for any questions you may have and don’t forget to start your free trial today.