Graphics Reference
In-Depth Information
There is one last thing to note about using fur materials with Global Illumination. Irradiance Caching (the
default Global Illumination engine) does not behave well with fur because of the way that lighting samples
are calculated. The Monte Carlo method is preferred for these materials for increased render speed. To set
the material to use Monte Carlo rendering, follow these steps:
1.
Create a new shader (from the Special section of the Add Layer menu).
2.
Place the shader inside the material group that contains the fur material.
3.
Select the shader and choose Monte Carlo from the Indirect Illum Type menu.
4.
Drag the entire material group above the base shader to allow the independent render type to become
active.
Using Replicators
Beyond grass on a lawn, there are other random elements in an outdoor scene. Rocks on the ground and
leaves on trees are the two examples demonstrated in this section. For these cases, I am using preset con-
tent, but the basic parts can easily be created manually. Rocks will provide a good starting point for working
with replicators and can be used to create rocks in the grass, driveway, street, or anywhere else that detail is
needed. Three items are needed to make a replicator work:
• A prototype (one or more items that are to be replicated)
• A point source (where the items will be placed)
• The replicator layer (which tells the other two items how to behave)
Start by adding a mesh that will be a rock. This can be either a preset mesh or a simple scratch-built mod-
el. Make sure that the polygons in the mesh layer are centered in space and sitting on the ground plane (the
Y = 0 coordinate). Replicators are capable of utilizing multiple prototypes, but for now a single mesh will
suffice. Also, in a second mesh layer, create a simple square with several subdivisions in both the x- and
z-axes. The basic building blocks are in place, as shown in
Figure 11-29
.
