8

958 Chapter 9: Surface Modeling
patch surfaces, which can generate more accurate
shading.
In the illustration below, a sphere was converted
to Editable Patch format, and then a vertex was
moved toward the center and rotated. The sphere
onthelefthasUseTruePatchNormalsturnedoff,
and the one on t he right has it turned on. In both
cases, View Steps was set to 8.
A patch sphere with Use True Patch Normals off (left) and
on (right).
Miscellaneous group
Patch S mooth—Adjusts all tangent handles to
smooth the surface of the patch object.
Patch Smooth sets the handles to absolute
positions based on the patch object geometry;
repeated applications have no effect.
A patch tube before smoothing (left) and after using Patch
Smooth (right)
Sur face Properties rollout
TheRelaxMeshcontrolsontheSurfaceProperties
rollout change the apparent surface tension by
moving vertices closer to, or away from, their
neighbors. The typical result is that the object gets
smoother and a little smaller as the vertices move
toward an averaged center point. You can see the
most pronounced effects on objects with sharp
corners and edges.
Relax—Turnsontherelaxfunctionforrenderings.
Relax V iewpor ts—Turnsontherelaxfunctionfor
view por ts.
Relax Value—Sets the distance a vertex moves as a
percentage of the distance b etween a vertex and
the average location of its neighbors. Range=-1.0
to 1.0. Default=0.5.
Iterations—Sets how many t imes Relax is repeated.
Each iteration recalculates average vertex locations
based on the result of the previous iteration.
Default=1.
Keep Boundary Points Fixed—Ver t i c e s at t h e e d g e
of open patches do not relax. Default=on.
Save Outer Corners—Preserves the original
positions of vertices farthest away from the object
center.