Not all cars drive on tarmac. Mike Griggs demonstrates how to create a realistically rough terrain for rallying.
Make a rough track
01 Create the base terrain
Make a simple plane, subdivide it a couple of times then convert it into a subdivision surface for sculpting into a rally track.
02 Sculpt in details
Use a Push tool to create a series of bumps in the surface and sculpt in some detail. Then add some noise displacement for extra texture.
03 Add the rocks
Using a duplicate of your landscape, reduce it to its constituent points. Now jitter the points and use them as a cloner source for your rocks.
Artist tips: four ways to make your car more credible
01 Custom car rigs
Most of the common apps have car rigs that enable you to add geometry to animate them. These can range from simple rigs, which just animate direction and wheel turning, to highly realistic plug-ins that can handle suspension and collision deformation. These more elaborate rigs do have a corresponding price, so the free, open-source 3D app Blender is a good place to start if funds are tight.
02 Create wear with occlusion maps
Occlusion maps are a good way to weather your car. An occlusion texture can be created by baking an ambient occlusion map then adding dirt in Photoshop. This is brought back into your 3D program as a mask for your texture. Alternatively, you can create cavity maps in programs such as ZBrush or xNormal. Some apps, such as modo, have a special texture to create modifiable occlusion layers.
03 Light using the golden hour
Lighting your car scene can go a long way to help your image. In car commercials (and Michael Bay films), the vehicles look amazing because they’re being shot in the golden hour, the soft light as the sun rises or sets. Apps with time and geography systems, which enable you to dial in the sunlight and control shadow direction and ambient daylight colour, are now entering the market.
04 Differences in tyres
Tyre pressures can change radically according to the type of terrain a car is on – snow requires less, tarmac requires more. The profile of the tyre can depict this pressure in different ways: a monster truck’s tyre will show the deformation of low tyre pressure much more than a rally car, for instance. Bigger, chunkier tyres will also throw up a lot more debris than more conventional rubber treads.