Sculpting - Blender Foundations: The Essential Guide to Learning Blender 2.6 - page 228

normal map image, which is like a
bump map's older, tougher brother.

Using the Multiresolution
Modiier
The Multiresolution modifier (Multires)
allows you to add subsurfacing, and make
each level of that subsurfacing editable.
Figure 8.6 shows the sample head with
several levels of Multires. The thing that
makes this different than a standard Sub-
division Surfacing modifier (Subsurf) is
that the mesh is completely editable at
each of these levels of resolution. Want
to add fine detail? Make changes at the
highest Multires level. Want to adjust the
proportions of the head? Make changes
at the lower levels and see them reflected
throughout the different levels. With a
regular Subsurf modifier, you always
have to work on the lowest-level cage
and don't have any say in what happens to all those little polygons that the modifier adds.

Figure 8.5 Finding the right view to move your geometry.

Blender does some neat tricks in the background to keep your system running smoothly even with very
high polygon counts, when coupled with the Multires modifier. It doesn't work very well in Edit mode,
but that's okay. The original intent of Multires was as a brother to the sculpting tools. With sculpt, it
works beautifully. Figure 8.7 shows the project head, set to Multires level 6, which has over 2.6 million
faces! On a dual-core laptop with on-board graphics and a measly 2 GB of RAM, the sculpting tools are
still quite usable. Desktop systems with better specs will get appreciably better results.

To begin adding detail to something like the head of your character, start a new Blender scene with Ctrl-N.
Bring in a copy of the head from your scene by pressing Shift-F1 or choosing Append from the File menu.
Navigate to your scene file in the browser and dig into the “Object” folder that is presented. Find your head
object, make sure that Link is disabled on the left side of the browser, and press the Link/Append from
Library button. This brings a copy of the head model into your Blender session. We're going to be doing
heavy-duty stuff to this model, and there's no need to clutter the main scene file with it.

In the Modifier context of the head's properties, add a Multiresolution modifier. The Multires panel is
shown in Figure 8.8 . In addition to the normal modifier controls, we have several banks of tools. The
Catmull-Clark/Simple selector determines whether the subdivision smoothes the mesh (Catmull-Clark) or
just adds extra geometry (Simple). Since our target for this extra detail is going to be a mesh that uses sub-
surface smoothing, leave it on Catmull-Clark. The stack of number buttons controls which Multires layer is