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1256 Chapter 9: Surface Modeling
Add To S et—
Adds an object to the Level of Detail
set.Youmustfirstattachtheobjectyouwantto
add to the group object. To add an object to the
set, use Align to center the object with the g roup
object. Select the object you want to add, and then
choose Attach from the Group menu, and then
click the group object. Finally, click the Add to Set
button, and then click the object you want added.
Remove from Set—Removes the object highlighted
in the list window from the current set. Note that
the object then becomes visible in the viewports,
butisstillpartofthegroup.Toremovetheobject
from the group, choose Group menu > Open,
select the object you want removed, and choose
Group menu > Detach. Select the group object
again, and choose Group menu > Close.
Image Output Size group
Width/Height—The Width and Height spinners in
this area are s et to the current rendering output
size each time you enter the Level of Detail utilit y.
Using the spinners, you can change this to any
resolution. If the percent of Target Image option is
selected, as you change the Target Image Size, the
thresholdvalueschangeaswell.
Reset to Current—Resets both spinners to the
current rendering output size.
List window—Lists all of the objects in t he group by
complexity, with the least complex at the top of the
list. The numbers at the left of each object name
are the threshold values that indicate at what size
theobjectwillbedisplayedintherenderedscene.
The numbers can be one of two types of units,
pixels, or percentage of the target image. You set
thetypeofunitintheThresholdUnitsgroup.
Display in Viewports—Displays in the viewport the
object highlighted in the list window. Only one
object in the group is displayed in the viewports at
any time. As a default, the least complex object is
displayed, but you can look at the other objects
by highlighting them in the list and selecting this
item. Double-clicking the object name in the list
performsthesamefunction.
Threshold Units group
The options in this group box let you choose
between two t ypes of threshold units. Switching
between these two options do es not alter the
effect; it alters the method by which you set the
thresholds.
Pixels—The thresholds are determined by
specifying the maximum pixel size of the image
(measured diagonally). Use when you want to set
the tra nsfer thresholds using absolute rather than
relative values.
%ofTargetImage—Sets the thresholds based on
thepercentageofthesizeoftheimage(measured
diagonally) relative to the size of the rendered
output.
Thresholds group
Min Size/Max Size—Sets the minimum size of the
object before it ’s replaced by the less complex
object, a nd the maximum size of the object before
it’sreplacedbythemorecomplexobject. The
values vary depending on the current type of
Threshold U nit. The default threshold values are
initialized so that the most complex object is 100
percentoftheimageoutputsize.Theremaining
thresholds are set using an algorithm based on a
ratio of the number of faces between each object.
It assumes that all faces are the same size, and then
picks thresholds so that the faces would remain a
constant size as displayed on the screen. Usually,
this will provide the type of smooth transition you
need, but you can customize the threshold values.
The threshold va lues are interrelated between
the objects, so altering the minimum size of one
object, for example, w i ll also alter the max imum
size of the next object.
Reset All—Resets all thresholds for all objects in
the l ist, using the previously described algorithm.