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Glow Lens Effect 225
channel is interpreted opposite that of the Mask
channel. Range=0 to 255.
ZBufferHiandLo—Highlights objects b ased on
their distance (Z-Buffer distance) from the camera.
The Hi value is the maximum distance and the Lo
value is the minimum. Any objects between these
two Z-Buffer distances w ill be highlighted.
Image Filters group
Filters t he Image Sources selections to let you
cont rol how the Lens Effect is applied. For
example, you can have ten spheres in your scene,
each with the same Object ID, but different colors.
IfyousettheImageSourceastheObjectIDofthe
spheres, which selects all of the spheres, these will
be the only objects in the scene that Lens Effects
will apply an effect to.
However, now that Lens Effects knows where the
pixels are that effects
can be applied, it needs to
know which ones to actually apply the effec t to.
LensEffectsusesthefiltercontrolstofindout
whichsourcepixelstoapplytheeffectto.
All—Selects all source pixels in the scene and
applies the Lens Effect to them.
Edge—Selects all source pixels along a boundary
edge and applies the Lens Effect to them. Applying
a Lens Effect along the edges of objects produces
asofthalothatexistsonbothinsideandoutside
edges of your object.
Peri m(eter ) Alp ha—Applies the Lens Effect only
to the perimeter of an object based on its a lpha
channel. Selecting this option applies the effect
only on the outside of an object without any
spill on the interior. Whereas filtering by Edge
produces a spill onto the object, Per imeter Alpha
keeps all of the edges clean because it relies on the
scene alpha channel to derive its effect.
Peri m(eter )—Applies the Lens Effect only to the
perimeter of an object based on Edge interference.
Although not as precise as Perimeter Alpha, you
might need to use the Perimeter option at times
when the a lpha channel is unavailable.
Bright—Filters the source objects based on their
brightness values. The effect is only applied to
objects with a brightness above the spinner setting
This option can be inverted by clicking the I
button next to the spinner
Hue—Filtersthesourceobjectsbytheirhue.Select
the hue by clicking the color swatch next to the
spinner. You c an choose hue values from 0 to 255.
The spinner beside the Hue color swatch lets you
enter a variance level s o that the glow ca n find
several different hues in the same range as the
chosen color
Additional Effects group
Additional Effects allows you to apply maps such
as Noise to your Lens Effect. You can display the
Material/Map browser by clicking the long button
next to the Apply check box.
Apply —Applies the selected map when act ivated.
Radial Density—Determines where and how much
you would like the additional effects applied.
Clicking the Radial Densit y button displays the
Radial Density dialog (page 3–252) .Usingthe
Radial Density dialog you can create points on
alineandmovethosepointsalongagraphto
determine where the additional effect should be
placed around the light. You can also use a map
to determine where the additional effect should
be placed.