Recently in a Civil 3d training course one of the students asked about creating a flat surface on a side of a hill for a big water tank pad. We created a 3d model of this and overlaid an aerial photo on the surface model. Then, we used the Civil 3D 2011 drive mode tool, to simulate how this water tank looks to a driver along the road. I thought this would be great to share with everyone for presentation purposes.
First, create the TIN surface model. In this example, I used contour lines saved in a shape file along with geo-referenced files to create my surface. I used the MAPIMPORT command to bring in all this data. I also happened to have an aerial photo with geo-referenced files as well, so I used the MAPIINSERT command to bring that in. Both of these required having a geospatial coordinate zone selected.Now, you can design the pad for the water tank using the grading tools. Create a finished surface model (FG Surface) by pasting the grading surface and the original surface model together. Your model should look something like the picture below. I used the CYLINDER command to create a generic model of a water tank.Next to make the presentation more realistic, we’re going to drape the aerial photo on to the finish surface. This will make drive mode look much better. First, select the surface and then on the contextual Tin Surface ribbon tab, click on Drape Image.Select the image when prompted to drape onto the FG surface. Change the visual style (VS in the command line) to Realistic to see the draped image. Hide the original image and you will see something like this.Finally, lets use the drive mode to simulate how the water tank and pad look as you drive along the road. We need to create an alignment along the road first if you do not have one already. Once you have that created, in the Ribbon, on the Analyze tab, in the Design panel, click Visibility Check, and click Drive.Select the alignment and surface when prompted. This opens up the Drive tab on the ribbon. Here you can find settings to control where the driver is looking. Click on the play/pause button to drive. As you can see in the ribbon, you can control eye level/angle and target as well as speed.Enjoy!