Baking navigation areas with different costs

In games with complex environments, we usually have areas that are harder to traverse than others. For example, crossing a lake with a bridge is less challenging than crossing it without a bridge. To simulate this, we want to make crossing the lake more costly than using a bridge. This section will look at navigation areas that define different layers with different navigation cost values.

For this, we build a scene, as shown in Figure 8.11. Three planes represent two ground planes separated by a water plane and connected by a bridge-like structure. As you can see, crossing over the water plane is the most direct way to traverse the lake; however, passing through the water costs more than using the bridge and, therefore, the pathfinding algorithm will prefer the bridge to the water:

Figure 8.11 – Scene with layers – NavMesh03-Layers.scene

Let's follow a step-by-step procedure so that we can...