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1372 Chapter 16: Material Editor, Materials, and Maps
Raytracing Acceleration
Pa r a met er s D i a lo g
Rendering menu > R aytracer Settings > Render Scene
dialog > R aytracer panel > Raytracer G lobal Parameters
rollout > Global R aytrace E ngine O ptions group >
Acceleration Controls b utton
The controls in this dialog let you o v erride the
default acceleration values and sp ecify your own
requirements. Typically you don’t need to use
them, but if you are familiar w ith the requirements
of your scene, they can help you optimize rayt r ace
rendering for your specific needs and time
constraints.
Raytracing subdivides the scene, organizing it into
a tree for raytrace purposes. A node in this tree is
known as a "voxel." Voxel t rees are dynamic, and
you can’t explicitly specify the structure of the tree.
(If you set Max. Divisions to 2, the tree is a n octree,
which is possibly a more familiar data structure.)
Tip: If your scene is very unbalanced (for example,
ithasagiantplanetobjectandaclusterofsmall
spacecraft objects) keep the Balance sett ing low.
Inter face
Face Limit—Sets the maximum number of faces
allowed in a lattice voxel before it is subdivided.
Default=10.
Balance—Determines the sensitivity of the
subdivision algorithm. Increasing this value uses
more memory but can increase performance.
Default=4.0.
Max. Divisions—Sets the initial lattice dimension.
For example, 4 is a 4 x 4 x 4 lattice. Default=30.
Max. Depth—Sets the maximum number of lattice
subdivisions. Default=8.
Raytrace Exclude/Include Dialog
Rendering menu > Raytrace Global Include/Exclude
Material Editor > Raytrace material > Raytracer Controls
rollout > Local Exclude button
Material Editor > Raytrace map > Raytracer Parameters
rollout > Local Exclude button
Rendering menu > R aytracer Settings > Render Scene
dialog > Raytracer panel > Raytracer G lobal Parameters
rollout > Global Raytrace Engine Options group > Exclude
button
Main toolbar > Render Scene > Render Scene dialog >
Raytracer panel > Raytracer Global Parameters rollout >
Global Raytrace Engine Options group > Exclude bu tton
Upper left: Bottle excluded from both mirrors
Upper right: Bottle reflected by both mirrors
Lower middle: Bottle excluded from one mir ror
These dialogs let you specify which objects the
raytracer will and won’t see. This is a good
optimization when you are working with complex
scenes and a ll you really need is for an object to
reflect itself or s ome other, simpler elements in the
scene.
The global dialog affects
all Ray trace materials and
Raytrace maps in your scene. The local dialog
affects only the current material or map.