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1700 Chapter 16: Material Editor, Materials, and Maps
the illusion that the surrounding maps are seen
through the surface.
Note: Reflect/Refract is meant to be used with
cur ved or irregularly shaped objects. For
mirror-like flat surfaces that you want to reflect
the env ironment accurately, use Flat Mirror (page
2–1695) material. For more accurate refractions,
especially for an object in a refractive medium
(such as a pencil in a g lass of water), use Thin Wall
Refraction material (page 2–1703).
Automatic Cubic Ma ps
When you choose automatic cubic maps, 3ds Max
generates the maps based on the perspective of the
mapped object’s pivot point. A utomatic maps are
based on the geometry of the scene.
The advantage to us ing automatic maps is that the
six views are automatically generated at rendering
time and can be easi ly updated for each frame of an
animation. The disadvantage is that regenerating
the maps increases rendering time. In addition,
the maps exist only for the rendering and can’t be
edited or otherwise manipulated.
In the Material Editor, automatic reflections or
refractions reflect or refract the background of the
sample slot.
Assigning Cubic M aps
When you choose to load cubic maps from files,
you use the controls in the From File group. The
advantage to using From File is that the bitmap
files already exist and take less rendering time.
In addition, you can edit the bitmap images.
Thedisadvantageisthatit’smoredifficulttouse
bitmaps to render an animation because first you
need to create the animated bitmaps.
Impor tant: Assigned cubic maps must be square, and
eachofthesixmapsmustbethesamesize.
Yo u c a n a u t o m a t i c a l l y l o a d s i x b i t m a p s a t o n c e i f
thesixbitmapshavevalidcubic-mapfilenames.
Thefirstpartofallsixfilenamesmustbethe
same, and the last part is an underscore followed
byatwo-letterabbreviationofthemapposition,
asshowninthefollowingtable:
Last Par t of Cubic Map File
Name
Meaning
_UP Up
_DN Down
_LF
Left
_RT
Right
_FR Front
_BK
Back
For example, if you have six bitmaps on disk,
labeled view_up.bmp, view_fr.bmp, view_lf.bmp,
and so on, when you click one of the file buttons
and choose the bitmap for that position, a ll six
views are loaded.
Ifyouselectabitmapwhosenamedoesn’tfollow
the convention, or you select one with a valid
cubic-mapnamebutassignittothewrongbutton,
only that bitmap will be loaded.
Since all assigned bitmaps must be the same
size, when you assign a new bitmap to one of
the windows, the sample slot doesn’t update
automatically. This avoids generating an error
message each time you assign a bitmap. Once
you’ve assigned al l six maps and are sure they are
square and the same size, click the Reload button
to update all of the maps and redisplay the sample
slot.
YoucanalsousetheReloadbuttontoseeyour
changes after you’ve edited one of the cubic maps
by using a paint program.
Rendering Cubic Maps
ThecontrolsintheRenderCubicMapFilesgroup
let you generate the maps automa tically and save
them to disk. Use the To File button to specify the