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Editable Patch (Patch) 975
Use True Patch Normals—
Determines how t he
software smoothes the edges between patches.
Default=off.
When the check box is off, the software computes
the surface normals from the smoothing groups
of the mesh object to w hich the patch object is
converted before rendering. These normals are not
accurate, especially with a low View/Render Steps
setting. When the check box is on, the software
computes true patch normals directly from the
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 the tangent handles of
vertices b elonging to selected patches to smooth
the surface of the patch objec t.
Patch Smooth sets the handles to absolute
positions based on the patch object geometry;
repeated applications have no effect.
Sur face Properties rollout
These cont rols let you work with patch normals,
material IDs, smo othing groups and vertex colors.
Normals group
Flip—Reverses the direction of the surface normals
of the selected patches.
Unif y—Flipsthenormalsofanobjectsothatthey
all point in the same direction, usually outward.
This is useful for setting an object’s patches
to appropriate or ientations, thus eliminating
apparent holes in the object surface.