Faster Scene Creation with the Vegetation Field

Creating immersive 3D environments is challenging. Users can be quick to notice elements that feel out of place or unnatural. In off-road environments, distributing vegetation assets organically can help achieve higher levels of engagement, but manual positioning is time-consuming. With Vortex Studio 2017a, we’re introducing a new procedural content tool, the Vegetation Field. It allows users to rapidly and efficiently add multiple copies of vegetation assets, such as trees, foliage, rocks and grass, to a scene. Instead of having to position each object one by one, the Vegetation Field randomizes and distributes them based on the density defined by the user. Each model is automatically snapped to terrain topography. The result is a natural-looking synthetic environment that can be achieved much more rapidly.

Local 150 training facility
Local 150 training facility

The density and distribution of objects can be controlled using a grayscale texture that will act as a density map. The color of each pixel defines the local density of objects. A pure white area means that vegetation in that spot is distributed randomly and the number of instances is maximal. A pure black area means there is no vegetation at the corresponding location. This can be used to identify paths and roads, for example. Gray areas in-between adjust the density based on their value.

While the Vegetation Field is normally used in conjunction with the library of SpeedTree assets included with Vortex Studio solo, team and academic editions, it can also be used with other assets. It can populate a village with multiple copies of a house model, for example, or a parking area with vehicles. Keep in mind that object distribution will be organic, and not in rows.
The Vegetation Field functionality has a few limitations that must be taken into account. First, while it automatically adjusts the level of details (LOD) of models based on the viewing distance, it is limited to the first LOD setting on SpeedTree models. It also doesn’t incorporate shadows, and while it can snap to terrain, this feature doesn’t work on heavy slopes. Therefore, it’s most useful to populate distant areas of a scene, with individual SpeedTree assets and Mechanisms used in areas where users are expected to interact with the environment.