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Setting Bulge Angles 1095
Bulge shape is interpolated as joint movement approaches
a bulge angle.
• Creating and shaping the cross sections
associated with the bulge ang le. A link’s cross
sect ions and its profile are spline controls of the
shape of the skin. To create and shape cross
sections, see Shaping the Bulge (page 2–1096).
Each bulge angle affects both neighboring links.
Therefore, each link contains a set of cross
sections for each bulge at both its parent and
child joint angles. For example, the forearm
link can be deformed by bulge angles associated
w ith both the elbow and wrist joints.
• Adjusting bulge parameters, including the joint
intersection parameters. Bulge parameters
control the smo othness and the strength of the
bulge and are found at the Bulge sub-object
level.
Joint intersection parameters control how the
skin behaves when bulges would overlap each
other if there were no collision detect ion for
skin vertices. They are in a Physique rollout for
Link sub-objects. See Reinitializing Physique
Settings (page 2–1098) .
See also
Bulge Sub-Object (page 2–1141)
S etting B ul ge A ngles
Abulgeangleassociatesananglevalueandaname.
By default, each link has one bulge angle whose
defaultnameisthenameofthelinkfollowedby
"Bulge 0". The default bulge angle’s initial angle
valueistheanglebetweenthelinkanditschild
when you first attach Physique to the skeleton.
Bulgesareeffectivebecausetheygrowandshrink
as the joint moves. The initial bulge angle defines
one shape that the skin can deform to; this would
normally be like a default musculature. With no
other bulge angles defined, the skin would alwa ys
look like the first bulge ang le, regardless of pose.
Additional bulge angles provide the other shapes
the mesh can deform to.
Inthesimplecaseofaflexingbicepsmuscle,
onebulgeangledefinestherelaxedpositionand
anotherdefinesthemuscleinitsflexedpose.
Both are exposed so you can add definition to
the default character. As in a biceps muscle, a
heavily-muscled character might have some shape
even in a relaxed pose. This lets you change the
baseline without disturbing the original mesh. You
can actually use Physique bulge cross sec tions to
model your character.
The cross section deformation for a given link
is determined by interpolating between the
contributions of all bulge angles that affect the
link.Thisincludesbulgeanglesforboththelink’s
parent joint angle and its ow n (child) j oint angle.
Each bulge angle’s contribution is determined by:
•Influence(howfarawaythebulgeangleisfrom
the current joint angle rotation)
• Power (an ease based on the influence of the
angle)
• Weight(therelativestrengthofthebulgeangle)