3D modeling programs vary in the types of geometry they'll create. Apps that lend themselves to manufacturing will often focus on NURBS surface and solid modeling. Rhino 7 falls into this camp but it also supports polygonal meshes and now SubD surfaces as well. Unreal Engine will use polygonal meshes which are the standard geometry type in video games and animations.

Unreal Engine can import the native Rhino 3dm file format using a plugin available in UE4 called Datasmith. Plugins are added per project via the Plugin Manager in UE4 so bringing in existing files is pretty easy but there are some details to consider in order to avoid issues.

• UE4 won't see SubDs yet that are saved in the Rhino 7 3dm, use the Mesh command in Rhino to convert them to polygonal meshes before saving the 3dm you'll Import with Datasmith.

• The normal direction of surfaces or meshes is important once in UE4. Make sure all the normals point towards the side of the object that will face the camera or you won't see it. Alternatively, make all objects closed solids so that the normals all point outward or change your materials to be double sided in UE.

In Rhino 7 you'll want to assign your materials and have everything looking as you'd like when previewed in the Rendered or Raytraced display mode or when using the Render command with the default Rhino Renderer. For the texture mapping properties of your objects, make sure to use either primitive mapping methods such as Box, Planar etc. or better yet make custom Unwrapped UVs for them. This becomes an important aspect of getting the proper tiling and repeat values for textures like wood and stone once in Unreal Engine.

You can use any of the material types Rhino 7 has to offer including the material library which is comprised of the Custom material type. Note that these library materials will include textures set to use Rhino's World Coordinate System (WCS) mapping method by default. Convert textures to Mapping Channel 1 within the material and edit the mapping per object as needed. WCS mapping from Rhino will not transfer properly to UE4 as of this writing.

The new Physically Based material type (PBR) in Rhino 7 will transfer to UE4 as well as any imported texture sets used to automatically create PBR materials. However, in some cases I had to change material properties in UE to match what I wanted as not all settings from PBR materials transferred properly.

Materials can be edited quite extensively in UE4 using a node based editor. It's dense with options and your imported materials get converted into nodes you can continue to edit as needed. I particularly liked the world displacement and tessellation multiplier material inputs for adding displacement to meshes but I ended up not using this on the gravel due to polygon count concerns.

There was a lot to learn in Unreal Engine and I feel as though I've only scratched the surface. I now know enough to be dangerous as they say and am quickly forgetting the questions I had at the beginning. Here are a few tips and tricks that took me a while to figure out.

• Start UE with the Game > VR template. This will have a couple 'maps' to choose from for the type of VR gear you're designing for.

• A scene has to be 'built' before you can 'play' it on the computer or in VR.

• Building is a combination of navigation and also lighting. Beware of 'lightmaps' having overlapping UVs.

• Lightmaps are a variation of each mesh object's UVs that is automatically generated. Simply put, if they overlap it looks bad. Lighting and shadow information is baked into the islands in these UV channels. You can often increase the Lightmap resolution for an object to fix this common issue but you may need to unwrap it again in UE as well.

• Objects you import are called 'actors'. Each actor has many properties that can be changed by double clicking it in the Content Browser. You can customize collision, material, lightmap resolution and mesh LOD density there.

• You can right click an object and use 'browse to asset' in the World Outliner to locate it in the content browser.

• Editing multiple objects at once is possible using what's called a 'property matrix' available in 'asset actions' with multiple objects selected in the content browser.

• If you need to reduce poly counts for lots of objects at once, reduce LOD 0 on one and then 'copy LOD' in it's right click menu in the content browser. Then you can select any other objects and 'paste LOD'.

Transferring the Unreal Engine project to the Oculus headset required a number of steps and project settings (see the Links page). The version of Unreal Engine that supported these also became a factor and I actually had to go back a version for things to launch properly. I recommend trying to launch the default VR template to your VR headset first to test version compatibility before designing your project.

• A free Oculus Developer account was required to upload to the headset and it needs to be in Developer mode set via the companion phone app.

• The Android SDK had to be installed on the computer with UE4.

• Android debug drivers had to also be installed on the computer.

• The UE4 project had to be configured for Android platforms.

• Oculus device support also required changing a large number of project settings in UE4 for a successful 'launch' which is the term for uploading the scene to the device in order to run it while not connected to the computer and UE4.