About a month or so ago, I started working with a user trying to find an easy solution for adding 3D objects, such as buildings and storage tanks, to his Voxler models. The customer was using Voxler to create graphics for a soil contamination report and wanted to give the stakeholders for this project a good frame of reference for where the contamination plume extended under the existing structures. Adding the buildings and storage tanks to the Voxler model paints a clear picture of the subsurface contamination extent. Voxler does not currently offer 3D drawing functionality, so I took a look at some 3rd party applications to find the best solution for the user.
Searching for the Right 3D Drawing Application
Voxler started supporting 3D DXF in version 4, so finding an application that exports 3D DXF in the correct coordinate space was the main requirement. The user also wanted the solution to be cost effective, so I kept this in mind during my search.
I started with SketchUp, which was free, and quickly found that it was easy to create the desired 3D objects. The only drawback with SketchUp is that it’s difficult to export the 3D objects in the desired coordinate space. Since this is a requirement, SketchUp didn’t make the cut. I then took a look at AutoCAD, which definitely is an attractive application as it will do what I need it to do; however, the price is a lot higher than the user wanted to pay. My next option was to try TurboCAD. I downloaded the demo version to see if creating 3D objects was easy and to verify that they exported in the correct coordinate space. TurboCAD was easy enough to learn, I was able to create objects in the desired 3D coordinate space, and the price was inexpensive. My decision was made; I recommended using TurboCAD for the user’s 3D drawing needs. The rest of today’s blog post discusses creating 3D structures in urboCAD, exporting them in 3D DXF, and adding them to an existing Voxler project.
Creating 3D Objects in TurboCAD:
In order to create objects in TurboCAD that were in the correct coordinates space, I exported a ground surface elevation grid from Voxler in 3D DXF format. I opened the DXF in TurboCAD by using the File | Open command, which gave me a nice palette to start drawing objects on. I also positioned the DXF so that I had a top-down view of it by clicking View | 3D Views | Top. Now I am ready to create some 3D objects such as some tanks and a building.
To create the building, I am going to use these steps:
- Zoom into the project using the mouse wheel to where the building is going to be located.
- Click Draw | 3D Object | 3D Primitives | Box and draw a box where the building footprint should be located.
- Rotate the view a little bit using the mouse so I can see a profile of the surface and box.
- Click Edit | Select to get the selection tool.
- Click on the box, when prompted click Box.
- Click on the top of the box and drag it up until it looks to be relatively the correct height.
Adding a box primitive to represent a building in TurboCAD.
Now that the basic primitive has been created for the building, I turned off the 3D surface so I could see the box better which allowed me to add a roof. There are a few ways to do this in TurboCAD, but since I’m new to TurboCAD I decided to add 2 wedges to create the roof:
- Click Draw | 3D Object | 3D Primitives | Wedge.
- With the mouse click on one corner of the box where the wedge should start and then click an opposite corner to make the base of the wedge.
- Drag the mouse up so that the wedge takes on the necessary height for the roof.
- Repeat these steps for the next wedge and to complete the roof.
Representing a roof in TurboCAD with Wedge primitives.
Now that the building looks good, it’s time to add a few subsurface storage tanks. This can be done by using the following steps:
- Turn the display of the 3D surface back on by clicking the eye icon under Layer.
- Rotate the display so that the underneath portion of the 3D surface is exposed.
- Start drawing the cylinder by clicking Draw | 3D Object | 3D Primitives | Cylinder.
- Rotate the view a little bit and extend the cylinder to an appropriate length.
- Click Edit | Select, and select the cylinder.
- Rotate the cylinder so that it’s in the correct orientation to the 3D surface and building.
- If necessary, move the cylinder down by adjusting the Pos Z value at the bottom of the TurboCAD interface.Adjusting the Z position for a storage tank by changing the Pos Z parameter In TurboCAD.
Now that the first storage tank has been created, I am going to copy it and paste another tank into the project. To do so I used the following steps:
- Click Edit | Select, and select the cylinder.
- Right-click on the cylinder, and choose the Rubber Stamp command.
- Position the tank in the appropriate location and click the mouse to insert the new cylinder.
- Check the elevation of the tank to make sure it’s good by checking the Pos Z value; adjust as needed. Both of the tanks should be at the same Pos Z.
The building and subsurface storage tanks have been added to the project; now they need to be rendered as solids in draft mode before they are exported for use in Voxler. To do so, right-click on the model in TurboCAD and choose the Draft Rendering option. The buildings also look nice if some additional color is added to them. Please note this is important to do in TurboCAD prior to export as Voxler will not allow you to change the colors of the DXF after it has been imported. Select one of the objects like the cylinder, then right-click and choose Properties. In the Properties dialog, select Pen and then change the drop-down menu under Color to change the color of the selected object. I changed the tanks to grey and the building to red and brown. The building and storage tanks rendered as solids with colors in TurboCAD.
Exporting the 3D Objects
Finally, I can export the building and tanks so I can use them in Voxler. Before I do so, I am going to delete the 3D surface so it is not included in the export. To do so, click Edit | Select and select the 3D surface and press the DELETE key. To export, click File | Save As. In the Save As dialog, name the file and make sure that the Save as type is set to DXF – Drawing eXchange Format and click Save. The DXF can be imported into Voxler and will locate in the correct coordinate space as shown in the image below. The final project in Voxler that contains the 3D buildings and storage tanks created in TurboCAD.