ZBrush Character Creation - Advanced Digital Sculpting 2nd Edition

■ Setting Up Your Scene for Displacement 317

use the mental ray Approximation Editor. Choose Window →

Rendering Editors → mental ray → Approximation Editor to

open the control panel shown in Figure 9.34. The Approximation

Editor lets you specify how much you want to subdivide the mesh

at render time. The higher the subdivision, the easier it is to pull

fine details in your render.

3. Be sure that Show In Hypergraph is checked and click the
   Create button next to Subdivision Approx. The Edit button
   will now become active; click it to open the options in the
   Attribute Editor.


4. Change the Approx Method to Parametric. Set the N
   Subdivision setting to 4 and press Enter. This will be a good
   start, but this value can be increased as you render to find the
   best balance between surface-detail quality and render time.
   The N Subdivision setting controls the fineness of the surface
   tessellation at render time.

Creating a Displacement Shader

Now we’ll create a shader for using a 32-bit floating-point map in
Maya. If your initial OBJ file has all its UVs in the 0 to 1 range, or
if it was mapped with AUV tiles inside ZBrush, you only have one
displacement map from ZBrush, and you will only need to create
one shader and apply it to your mesh. For rendering multiple maps,
see “Setting Up Multimap 32-Bit Displacement Renders in Maya”
later in this chapter.

1. Open the Hypershade by choosing Window →
   Rendering Editors → Hypershade.


2. Create a Blinn material by dragging it to the
   workspace from the left window. I use a Blinn
   shader because it has a specular channel and
   this slight highlight helps spot finer details on
   the displaced surface.


3. MMB-drag a displacement node over the
   material. Select Displacement Map from the
   Connection Editor window that appears
   (Figure 9.35). Double-click the displacement
   node to open the attributes. You need to tell the shader it will use a file for displace-
   ment. Click the check box to the right of the Displacement attribute. This will bring
   up the Create Render Node window. In this window, select File to create a File Node
   and connect it to the Displacement node.
   This creates a file node in which you can place your displacement map. You
   can graph your shader by selecting Blinn. Then in the Graph menu, select Input and
   Output Connections.
   Your shader graph will now look like the one shown in Figure 9.36.

Figure 9.33 Deselect the Feature

Displacement option.

Figure 9.34 The mental ray Approximation Editor