ZBrush Character Creation - Advanced Digital Sculpting 2nd Edition

308 chapter 9 ■ Normal Maps, Displacement Maps, Maya, and Decimation Master

Figure 9.23 UV Master can correct overlapping UVs quickly and easily.

Figure 9.24 shows an acceptable UV layout for a model. The UV shells are all in the dark

gray square, which represents the 0 to 1 range. This will generate a single map in ZBrush that

applies to the entire mesh. The multiregion layout in Figure 9.25 will allow you to interactively

hide parts of the mesh using the UV Groups option (as discussed in Chapter 3). This layout will

also enable you to generate multiple displacement maps for your mesh so that you can spread

the body parts out across multiple maps, thus giving more texture space to the displacements.

For example, the head, torso, legs, and tail may each have a displacement map at 4096× 4096

resolution as opposed to spreading the detail for the entire body over one 4096 map.

If for any reason you need to change the UV coordinates of the model before generat-

ing maps, this is no problem. Simply load the OBJ into ZBrush and use the UVMaster Copy

And Paste UV function to move coordinates between meshes.

You can also change UVs on an OBJ outside ZBrush. Perhaps you prefer to lay out

UVs with the headus UVLayout, for example. Again, this is no problem. Simply import the

new UVs directly into your ZTool. I’ll show you the process of transferring a model from

ZBrush to Maya and back to ZBrush seamlessly next.

You can move the OBJ file between applications as long as the vertex order remains

unchanged. Vertex order is changed by cutting new faces, deleting faces, or reordering on

import. Use the following process any time you transfer your model between Maya and

ZBrush:

1. In ZBrush, select Tool → Geometry and set SDiv to 1. Export by choosing Tool → Export.
   Be sure the iFlip and eFlip options are off and Mrg is on.


2. Save the mesh as an OBJ file.