Sculpting the Rock:
I started out sculpting the largest rock in ZBrush, the template of which was a simple rectangle from Maya. After I was done sculpting I created a duplicate from inside Zbrush and decimated the mesh which I also used to lower the topology from 1612738 tris to 2688. I then exported the high and low poly, then imported the low poly into Maya where I began to unwrap and layout the UV’s.
Creating the Material:
I then hooked everything together inside Unreal’s Material Editor, however, I like to have a lot of control over how I want the material to look and behave, so I use a series of nodes and parameters to help me achieve this. Here I have control over the power of the ambient occlusion which determines how much it spreads, as well as the colour of the AO. I can also change the colour of the surface, add an addition tint, increase the strength of the edges, and scale the normal map coordinates and the intensity of the normal map.
The Landscape Material:
For the landscape material, I created 4 material functions, one for each material I wanted to paint onto the surface, grass, dirt, mud and puddles. With the exception of the puddles, I created each one as I would if it were a normal material, which adding additional nodes to give me some basic control over the shaders behaviour and appearance such as being able to tune the strength of the brightness, spec and roughness, and also able to tile each texture.
Creating the Textures:
I then loaded both the high and low poly mesh into xNormals and generated a Normal and Ambient Occlusion map. I then took these into Photoshop and loaded Quixel Suite nDo, where I created an Edge and Cavity map. I also removed any unwanted shadows from the diffuse texture as well as adding addition an additional tillable normal map. I then assigned the edge, cavity and ambient occlusion map to their own channels, this saves me from having to save each texture separately.
The Puddle Material:
The puddles are set up to work in conjunction with the height and normal information of each of the grass, dirt and mud materials. Again, wanting to have as much control as possible it was important to be able to make changes to the material even after it’s been applied. Here I can change the depth, opacity, colour and size of the puddles, the wetness, and the normal shift. Lowering the value of the normal shift will remove any normal information that it may be receiving from the other materials from underneath giving the illusion of one large puddle while increasing this value will use that normal information to create several pockets for the puddle material to sit inside.
The Water/Caustic Material:
The water reflection materials were done by using a simple caustic texture which I then duplicated and set each one to animate at a different speed and direction. By setting the Material as a ‘Light Function’ I could attach it to a light source it had sitting just beneath the surface of the pond.
For the water material, I had the normals working the same way the Caustic material was. I simply used a Vector 3 Parameter so I could control the colour of the water, which was hooked up to a Lerp together with a Fresnel node.
