Autodesk 12812-051462-9011 User Guide 3 - Page 2722

Filtering (Antialiasing) Filtering is a technique of antialiasing the bitmaps in mapped materials by averaging pixels. The Pyramidal and Summed Area options provide two methods of pixel averaging. Only one can be active at a time. Both methods require approximately the same rendering time. Summed-area filtering generally yields superior results but requires much more memory. Pyramidal filtering requires the program to allocate memory equal to approximately 133% of the size of the bitmap. By comparison, summed-area filtering requires the program to allocate approximately 400% of the size of the bitmap. Use summed-area filtering only for smaller bitmaps, and avoid using any more such bitmaps in a scene than necessary. Pyramidal filtering is quite adequate for most purposes. However, because it applies filtering as a function of distance, irregular antialiasing might occur on detailed texture maps that are applied to a plane receding into the distance. The effect of pyramidal filtering on extreme perspectives such as this is even more noticeable in animations, where portions of the texture map appear to "swim." If this occurs, turn on summed-area filtering for the material. NOTE To control whether or not a background image is affected by the renderer's antialiasing filter, choose Customize > Preferences > Rendering on page 7768 and then turn on Filter Background in the Background Antialiasing group. Filtering (Character Animation) Filtering is the action of using selected data, rather than all data. In the Motion Mixer on page 3699, you use the trackgroup on page 8151 filter to select the biped parts that will be affected by motion clips and transitions on tracks within the trackgroup. See Filtering Mixer Tracks on page 3715. Filtering is also a motion-capture technique on page 4574. Motion-capture and marker data typically have keys at every frame. Filtering motion-capture data reduces the number of keys, making the job of altering or personalizing the motion data simpler. Other filtering options include footstep extraction, applying the skeletal structure stored in the motion-capture file to the biped, looping the data, importing a portion of the motion capture file, and selecting tracks to load. See Filtering Motion-Capture and Marker Data on page 4577. Glossary | 7977