ZBrush Character Creation - Advanced Digital Sculpting 2nd Edition

246 chapter 7 ■ Transpose, ZSphere Rigging, Retopology, and Mesh Extraction

5. Step down a subdivision level and stroke with the ZProject brush. This will have the
   effect of snapping the erroneous points to the surface. It is often helpful to smooth, then
   project and alternate between ZAdd and ZSub, depending on how deep into the mesh
   the points penetrate. Figure 7.45 shows the process of correcting this armpit defect. The
   ZProject brush works by projecting or pulling faces directly down the z-axis, so you
   will need to rotate around the figure as you work, snapping the vertices to the high-res
   with the brush.

Figure 7.45 Minor errors can be corrected with the Smooth or ZProject brush.

Be sure Transparent is on.

Importing a Mesh Directly

Finally, the most direct method of changing the topology is to import a mesh directly into

the existing ZTool. This approach uses a projection method similar to the one we discussed

earlier, but you will not have access to any settings. ZBrush will simply replace the lowest

subdivision level with the imported mesh and project those surfaces that are in close prox-

imity to the original. Any areas that do not correspond to part of the original ZTool will

not be projected. These areas will be masked. To import a new mesh, follow these steps:

1. From the DVD load remeshedManHead.ztl. This is a ZTool of a generic male head sculpt
   remeshed with animation-ready topology.


2. Step down to the lowest subdivision level. From the Tool menu, click Import and browse
   to manWithHorn.obj. This is a new base mesh with horns extruded from the original
   topology.


3. ZBrush will note the difference between the two meshes and open the Import Mesh
   dialog box; you click Yes to transfer the high-resolution details or click No to delete
   the higher resolution details (Figure 7.46). For this example, click Yes so ZBrush will
   project the new base mesh into the ZTool. Clicking No would delete the higher levels
   and leave you with the new base mesh and no sculpted details.


4. The new mesh will replace the low-res one. Figure 7.47 shows the ZTool immediately
   after the projection. ZBrush will return the highest subdivision level. Any parts that
   did not project will be unmasked, allowing you to easily polygroup them independently
   of the projected areas of the mesh.
   While this example used the extreme case of extruding new geometry off the model, it is
   just as effective when you simply need to change the edge flow or add new topology in an existing
   mesh. This is the same process used by the GoZ script when transferring models from ZBrush
   to Maya and making topology changes. With GoZ, the export and import steps are done by the
   script whereas in this case we simply imported the new mesh manually. The projection method is
   the same.