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1368 Chapter 16: Material Editor, Materials, and Maps
Lock button—
Locks the Environment map to
the Transparency Environment map. When on,
the Transparency Environment map controls
are disabled, and a map applied to the Raytrace
Environment applies to the Transparency
Environment as well. When off, the Transparency
Environment map controls are enabled, and the
Transparency Environment can have a different
map assigned to it. Default=on.
Changing this button’s setting here als o changes it
on the
Basic Parameters rollout (page 2–1355) ,and
the
Extended Parameters rollout (page 2–1360) .
Diffusion Mapping
The Diffusion map component lets you apply an
additional, second texture to modify the Diffuse
component. Typically, you will want to reduce the
Amount of this map to allow the main Diffuse
map to show through.
For example, you might have a clean, bright image
forabillboard.YouusethisimageastheDiffuse
map,andthenuseasecondmapasaDiffusion
map to apply soot and city grime.
Tip: An imating the Amount can change the
appearance of the material over time, letting
the Diffusion map either conceal or reveal the
underlying Diffuse map.
Note: Show Map In Viewport does not display the
Diffusion map.
Raytrace Dynamics Properties
Rollout
Material Editor > Type button > Material/Map Browser >
Raytrace material > Dyn amics Properties rollout
As with a standard m aterial, the Dynamics
Properties rollout for a
Raytrace material (page
2–1353)
lets you specify surface properties that
affect the animation of an object upon collision
w ith another object. If there are no collisions in
your s imulation, these settings have no effect.
Since the Dynamics Properties rollout is available
at the top level of any material (including
sub-materials), you can specify different surface
dynamic properties for each face in an object.
There are also controls in the Dynamics utility that
let you adjust the surface properties at the object
level, but only the Materials Editor lets you alter the
surface properties at the sub-object level, through
use of a
Multi/Sub-Object material (page 2–1403) .
As a default, the values in the Dynamics Properties
rollout provide a surface that’s similar to
Teflon-coatedhardenedsteel.
Interfa ce
B ounce Coeffi cient—Sets how far an object bounces
after hitting a surface. The higher the value, the
greater the bounce. A value of 1 represents a
"perfectly elastic collision," or a bounce in which
no kinetic energy is lost. D efault=1.0.
If you’ve seen the desktop toy with four ball
bearings swinging back and forth on strings and
hitting one another, you’ve seen an example t hat
comes very close to a b ounce coefficient of 1.
Generally, hardened steel or a super ball have a
bounce near 1, while lead has a bounce near 0.
Static Friction—Sets how difficult it is for the object
to start moving along a surface. The higher this
value, the more difficult. Default=0.0.
If something weigh s ten pounds and sits on Teflon
(a st atic fric tion of near 0), it takes almost no force
to make it move sideways. On the other hand, if it
sits on sandpaper, then the static frict ion might
be very hig h, on t he order of 0.5 to 0.8. A static