Terrain Data from Shapfile Contours

Terrain Data from Shapfile Contours

So, you downloaded some terrain and you ended up with an ESRI Shapefile that contains contours and you want to add that to your model as terrain. Well, it really isn’t difficult, you just need to understand a couple things first. For this example, I’m going to use a shapefile containing contour data for the entire City of Denver. You can get your own version of it at data.denvergov.org if you want to try this too. This shape file has around 650,000 contours that range from 5,110′ to 5,754′ at 2′ increments.

Contour Data Shown in Map 3D

Contour Data Shown in Map 3D

First of all, you add the shapefile to your model exactly the way you do any other shapefile, simply drag it into your model (drag the file with the extension .shp). Once you’ve added the shapefile, you’ll need to configure it. If you did the drag and drop, the configuration should just pop up for you. first thing you’ll need to do is tell it what type of data the shapefile contains.

Configure Data Type

Configure Data Type

If we simply stop here (which is what I did the first time I tried this), we won’t get any terrain information. Shapefiles have about as much standardization between organizations as layers do. We need to tell InfraWorks what the elevations of each contour is. In this example, the elevation of the contour is found in the data property called ELEV. We now need to map that value to the contours. This is done on the Source tab.

Setting Elevations

Setting Elevations

You’ll notice that I assigned elevations to the data being brought in from the data source “ELEV”. You’ll also noticed I multiplied the elevation by 0.3048. Your InfraWorks database is ALWAYS in meters. If you bring data into your model that isn’t being converted via a coordinate system (such as elevations) you’ll need to convert that data yourself. I also toggled on the “Clip to model extents” option. This just makes the data process faster as it doesn’t do anything outside of the model extents (not really sure why you would ever want to leave this unchecked).

And here’s the result!

Terrain from Contours

Terrain from Contours

Now, if you notice, the surface looks very gridded. When I created a surface in Civil 3D from this same data, it looked much better. This is because we told it to be gridded. If you have very complex data (such as contour data from a shapefile) you can simplify the data by putting it in a grid. It will process much faster and your model will work much better but, you’ll sacrifice the detail for performance. If you need the detail, you can change the grid factor or simply turn it off. The settings can be found on the Converter tab when configuring the data. You can adjust the size of the grid to control how much detail you get or you can turn the grid off complete to maximize the detail.

Grid Options

Grid Options

To see the results, I’ve turned the imagery off so the surface can be seen better. Here it is with the grid turned on.

10 Meter Grid

10 Meter Grid

And here is that same area with the grid turned off.

Grid Turned Off

Grid Turned Off

Hope this helps understand how to add even more data to your model. Now, get out there and do something amazing!

Advertisements