If you have never used a DEM (Digital Elevation Model) file I encourage you to search one out and put it to work for you. They are great for those preliminary designs or doing hydrology basins. DEM models can be downloaded for free from most Geospatial websites. They are excellent for generating relief maps so you can get a better perspective of the land or to impress your clients with 3D views of their property. What I want to do with them is show you how to create 3d rendered DEM. Most of you know that you can do it in Civil3D but did you know you can do it quicker and easier with the Map tools.
Lets jump in………..
To connect to a DEM to Map you must use the Add Raster or Surface Connection selection. Browse for your DEM directory and use the connect button to have Map read the directory.
Once Map scans the directory it will show the available data for connection. You have some choices at this point to change the coordinates and combine multiple items into one layer. Once your OK with the selection click the Add to Map button. (There are some other choices under the Add to Map button that I encourage your play with.)
So now you have a ugly green relief map. Yeah!
Go back to your task pane and select the DEM and click the style button.
Click the All Bands button. This will give you choices on how to display your map.
Select the Theme from the Style pull down.
I like the USGS National Map palette. USGS has used it so much I can just identify with it better. I also changed the distribution type to “Jenka”. It gives some better grouping of elevations.
OK out of all your dialogs. And one more setting. Type maphillshade at the command line. This will give some shadows to the hills and give them better perspective. Lots of choices in this dialog and connecting dialogs. You can select the DEM location and time or pull it from Google Earth. Play around with the settings. They create different shadows at different times of the day.
Well finally we have a 3d view of the DEM.
Ok here’s the great part about map. File size is (drum roll).
Not too bad. Well the next part is to do this all with C3D.
I won’t bore you with those details but I created a new surface and added the DEM to it. I used analysis tools to show the elevations. Had to tweak some default settings on the elevation style (Land is about as close as you can come to the USGS Map National Palette). All this and my 3d view wasn’t even as pretty.
I started playing with object viewer and rendering but it still didn’t cut it. And the file size?
Big difference. But it should be. C3D is made to give you all that data for design. You can do much more with the C3D surface than you could ever do with the Map version. But for a quick rendered relief projection, Map does a good job.