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Raytrace Dynamics Properties Rollout 1527
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 Transp arency
Environment map controls are enabled, and the
Transparency Environment can have a different
map assigned to it. Default=on.
Changing this button’s sett ing here also changes it
on the Basic Parameters rollout (page 2–1514),and
the Extended Parameters rollout (page 2–1519).
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: Animating the Amount can change the
appearance of the material over time, letting
the Diffusion map either conceal or reveal the
underlying Diffus e map.
Note: Show Map In Viewport does not display the
Diffusion map.
Raytrace Dynamics Properties
Rollout
Material Editor > Type b utton > M aterial/Map Browser >
Raytrace material > Dynamics Properties rollout
As w ith a standard m aterial, the Dynamics
Properties rollout for a Raytrace material (page
2–1512) 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 simulation, these settings have no effect.
Since the Dynamics Properties rollout is available
at the top level of any material (including
sub-materials), you c an specify different sur face
dynamic pro perties 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 proper ties at the sub-object level, through
use of a Multi/Sub-Object material (page 2–1594).
As a default, the values in the Dynamics Properties
rollout provide a surface that’s similar to
Teflon-coatedhardenedsteel.
Interfa ce
B ounce Coefficient—Sets how far an object bounces
after h itting a surface. The higher the value, the
greater the bounce. A va lue of 1 represents a
"perfectly elastic collision," or a bounce in which
no kinetic e nergy is lost. Default=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 that
comes ver y close to a bounce coefficient of 1.
Generally, hardened steel or a super ba ll 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 weighs ten pounds and sits on Teflon
(a static fr ic tion of near 0), it ta kes almost no force
to make it move sideways. On the other hand, if it
sits on sandpaper, then the st atic friction might
be very high, on the order of 0.5 to 0.8. A static