310 chapter 9 ■ Normal Maps, Displacement Maps, Maya, and Decimation Master
- In Maya, choose File → Import → OP and
select OBJ for the file type (Figure 9.26).
Make sure that Create Multiple Objects is
unchecked. If this box is selected, Maya will
not preserve the point order and your model
will not reimport into your ZBrush. - Make any UV changes you want and export
the OBJ again. - In ZBrush at subdivision level 1, choose
To ol → Import and select the new OBJ file.
The UVs will automatically update to the
ones in your new OBJ file. You can verify
the updated UVs by using the Morph UV
function under Tool → U V Map.
If you import a model into ZBrush and the
vertex order has changes, it may appear to import
fine. The problem manifests when you try to step
up subdivision levels. The mesh will explode, as
shown in Figure 9.27.
Figure 9.27 Changing the vertex order outside of ZBrush can cause meshes to explode.Generating Displacement Maps
ZBrush is capable of creating 16-bit and 32-bit maps in single-channel grayscale or three-
channel RGB. In this section, we’ll discuss how to create two kinds of displacement maps,
16-bit and 32-bit. Regardless of the type of map you generate, it is important to be aware
of the shape of the base mesh from which you generate compared to the mesh on which you
will render it.Figure 9.26 Import options in Maya. Note that Create
Multiple Objects is not selected.