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Subdivide M odif ier 839
Subdivide Modifier
Make a selection. > Modify panel > Modifier List >
Subdivide
Make a selection. > Modifiers menu > Radiosity Modifiers
> Subdivide
The Subdivide modifier provides an algorithm
forcreatingmeshesusedforradiosity (page 3–51)
processing. Pro cessing radiosity requires meshes
that have elements shaped as close as possible to
equilateral triangles. The density of the mesh
also needs to be considered in determining the
resolution of the lighting details that need to b e
captured. The denser the mesh is, the finer the
lighting detail and accuracy will be. The trade-off
is a larger memory requirement and slower
rendering times. The Subdivide modifier works
on a whole object and does not work on selected
facesinamesh.
Subdivide modifier breaks flat surfaces into meshes.
Although it is primarily developed for increasing
the qua lity of radiosity solutions, the Subdivide
modifier can also be used by any application
that requires well-formed meshes. For example,
irregular mesh elements generated for Te r rain
(page 1–347) compound objects can be impr oved.
The modifier has world space and object space
variants. In the world space modifier the size limit
is on the mesh after it is transformed into world
spacecoordinates. Theobjectspacemodifier
limitsthesizeinobjectspacecoordinates.
Note: Typically, the Subdivide modi fier is applied
automatically to objects in the scene when
a radiosity solution is processed. Meshing
parameters can be set on a global basis in the
radiosity control panel (page 3–61) or for individual
objects in the Object P roperties dialog (page
1–117).
Tip: When you are satisfied with the subdivision
settings on one object, you can drag the modifier
to other objects to propagate it.
Interfa ce
Size—Controlsthesizeoftrianglesinthe
subdivided mesh. The length of the longest edge
ofanytrianglewillnotexceedthesquarerootof
2 times the size in the Subdivide modifier. The
square root of 2 factor is used, so that a square
whoseedgesarethesizewillnotbesubdivided.
Update group
The radio buttons in the U pdate group control
when the meshing is done.
Automatic—Updates immediately when changes
aremadetothecontrolsorthemesh.
Render—Updates only for rendering.