9

UVW Map Modif ier 925
one axis, and a UVW Map modifier has a tiling
valueof3onthesameaxis,thentheresultisa
tiling value of 6.
Objects with No M a pping Coordina tes
If you render an object that doesn’t have mapping
coordinates or a UVW Map modifier, and the
object uses a material with 2D bitmaps or 3D
procedural maps that use explicit map channels,
then a Missing Map Coordinates (page 2–1623)
alert is displayed. The alert lists both the name of
the object and the UVW channels or Vertex Color
channels that are missing the coordinates. For
example: (UV W 2): Torus01.
Ma pping S election S ets or Gr ouped
Objects
You can apply one UVW Map modifier to a
selection of objects. One large mapping gizmo will
encompass the entire selection un less the Use Pivot
Points option is turned on in the modifiers rollout
before apply ing the UVW Map modifier. If the
Use Pivot Points option is u sed then each object is
encompassed with its ow n mapping gizmo.
If any of the objects in the selection has had its
pivot point shifted in the Hierarchy > Pivot panel,
and you use the Use Pivot Points option with the
UVW Map modifier, then the mapping gizmos are
centered to the pivot points rather than the object
center and the mapping may be tricky to position
the way you want.
Real-World M apping
The idea behind real-world mapping is to simplify
theuseoftexturemappedmaterialswhichare
scaled correctly with t he geometry in the scene.
This feature gives you the ability to create a
material and specif y the actua l width and height of
a2Dtexturemapinthematerialeditor.Whenyou
assign that material to an object in the scene, the
texture map appears in the scene with the correct
scaling.
There are two par ts to the equation in order for
real-world mapping to work. First, the correct
style of UV texture coordinates must be assigned
tothegeometry.Basically,thesizeoftheUVspace
needs to correspond to the size of the geometry.
Therefore, a new switch, c alled Real-World Map
Size, has been added to many of the dialogs
and rollouts where you c an generate texture
coordinates. Any dialog or rollout in which you
havetheoptiontoturnonGenerate Mapping
Coords,alsohasaswitchwhereyoucanturnon
Real-World Map Size.
Note: There are a few primitive objects that do not
have a Real-World Map Size switch. T hese are
Torus Knot, Hedra, Prism and RingWave.
The other p art of the equation is in the material
editor. When you create a material and use a 2D
texture map, you now see a new switch in the
Coordinates rollout called Use Real-World Scale.
When this switch is turned on, t he default, the
Width and Height spinners are enabled that let
you specify the horizontal/vertical offsets and size
of the texture map in current display units (page
3–848).
Note: Autodesk VIZ scenes with objects using
real-world mapping coordinates will display
differentlywhenopenedin3dsMax. Thisis
because real-world mapping coordinates is not the
default method of generating mapping coordinates
in 3ds Max.
Procedures
To apply the UVW Map modifier:
1.
Assign a mapped material to an object.
2. OntheModifypanel,chooseUVW
Map f rom the Modifier List.
3. Adjust the mapping parameters.