9

IK So lution 955
joint of a kinematic chain. By default, its name is
IK Chain01.
The kinematic chain is a single branch of a
hierarchy used for animation with inverse
kinematics (IK) (page 3–958).Thechainstarts
w ith the end joint and travels up through ancestors
until it reaches the start joint. When you move the
IK goal, the IK solver then uses IK calculations to
move and rotate all other objects in the kinematic
chain to react to the object you moved.
Note: YoucanmovetheIKgoalawayfromtheend
joint, which causes the IK chain to straighten out.
Whenyoumovethegoalbacktowardtheend
joint, joints in the IK chain will bend again.
See also
End Effector (page 3–933)
IK Solution
Inversekinematics(IK)usesagoal-directed
method where the animator positions a child
object and the progr am ca lculates the position
and orientation of the parent objects. The final
position of the hierarch y after all of the calculations
have been solved is referred to as the IK solution.
Applied IK requires that one or more parts of
your IK str ucture b e pinned to animated follow
objects. Once pinned, you select any object in your
kinematic chain and click the Apply IK button.
The software then calculates the IK solution for
each fr ame of the animation and places transform
keys for every object in the IK chain.
I llumina nce
Illuminance is the luminous flux (page 3–965)
incident on a surface of unit area. It measures how
much energy has fal len on a surface.
This quantity is useful for descr ibing the level of
illumination incident on a surface without making
the measurement dependent on the size of the
surface itself. The lux (lx) is the International
System (SI) unit of il luminance. The American
System (AS) unit for illuminance is the footcandle
(fc), equivalent to 1 lumen per square foot.
Illuminance is a function of the distance from the
light source. To specify t he illuminance of a light,
you must enter a va lue in lx, and the distance at
which that illuminance is measured.
Image Motion B lur
Image motion blur has been applied to the falling coin on the
right.
Motion blur can enhance the realism of a rendered
animation b y simulating the way a real-world
camera works. A camera has a shutter speed, and
if significant movement occurs during the time the
shutter is open, the image on film is blurred.
3dsMaxprovidesacoupleofwaystogenerate
motion blur. Image motion blur is one. Scene
motion blur (page 3–1007),aVideoPostScene
Event (page 3–329) effect, is anothe r. For most
purposes, image motion blur gives better results
thanscenemotionblur. Scenemotionblurisa
more exaggerated effect. You can use both image
and scene motion blur in the same rendering.