9

Select Bitmap Image File Dialog 1635
Alpha Sou rce group
Controls in this group determine the source of the
Output alpha channel in terms of the input bitmap.
Image Alpha—Uses the image’s alpha channel
(disabled if the image has no alpha channel).
RGB Intensity—Con v erts the colors in the bitmap
to g rayscale tonal values and uses them for
transparency. Black is transparent and white is
opaque.
None (Opaque)—Does not use transparency.
Premultiplied Alpha—Determines how alpha is
treatedinthebitmap. Whenturnedon,the
default, premultiplied alpha (page 3–997) is
expected in the file. When turned off, the alpha is
treated as non-premultiplied, and any RGB values
are ignored.
Tip: IfyouapplyanalphaimageasaDiffusemap,
for example, and it doesn’t decal correctly, the
bitmap file probably contains non-premultiplied
alpha; the RGB values are maintained separately
from the alpha va lues. To correct this, turn off
Premultiplied Alpha.
Time rollout
Thesecontrolsletyouchangethestarttimeand
speed of animation (AVI (page 3–609) or MOV
(page 3–621)) files used as animated texture maps.
They make it easier to use sequences of images
as maps in scenes, because you can cont rol the
timing ver y precisely
Start Frame—Specifies the frame where the
playback of the animated map will begin.
Playback R ate—Lets you speed up and slow down
theratethattheanimationisappliedtothemap
(for example, 1.0 is norm al speed, 2.0 is twice as
fast, .333 is 1/3 as fast).
Sync Frames to Par ticle Age—When on, the
software sy nchronizes the frames of a bitmap
sequence to the age of particles to which the m ap
is applied. With this effect, each particle displays
the sequence from the start when it is born, rather
than being assigned w hichever f r ame is cur rent.
Default=off.
WhenusingParticleFlow,assignthematerial
containing the Bitmap map to a Material Dynamic
operator. For more details and a procedure, see
Material Dynamic Operator (page 2–191).
Note: This functionality is not supported by the
mental ray renderer.
End Condition group
Determines what happens after the last frame of
the bitmap animation if the animation is shorter
than the s cene.
Loop—Causes the animation to repeat over and
over again from the beg in ning.
Ping-Pong—Causes the animation to be played
forward and then backward repeatedly, making
every animated sequence "loop smoothly."
Hold—Freezes on the last frame of the bitmap
animation.
Select B itmap Image File Dialog
Material Editor > Maps Rollout > Click any m ap selector
button. > Material/Map Browser > Double-cli ck Bitmap. >
Select Bitmap Image.
Material Editor > Bitmap map > Bitmap Parameters
rollout > Bitm ap button
The Select Bitmap Image dialog allows you to
chooseafileorsequenceoffilesforamap. If