2009

Update If you change a parameter in the particle system, the cached data
might become invalid. This setting determines whether Particle Flow should
update the cache automatically, or let you do it manually. Default=Always.
■ Always Changing any parameter under the Cache operator's purview
causes it automatically to update stored data from the start of the current
range (see next parameter) to the current frame.
■ Manually Updating occurs only when you click the Update button, or
clear the cache and then move to a different frame.
Range Sets the frame range within which the Cache operator operates.
Default=Active Segment.
■ Complete The software caches the entire animation.
■ Active Segment The software caches only frames in the active segment,
as defined by the Start Time and End Time settings on the Time
Configuration dialog. This is the frame range shown on the track bar. You
can also change the active segment by holding down Alt and Ctrl and
dragging the track bar with the left, middle, or right mouse button.
■ Custom The software caches only frames in the custom range, as defined
by the Cache operator's Start Time and End Time settings (see following).
NOTE If you cache only part of the animation, Particle Flow calculates particle
behavior in subsequent, non-cached frames using the cached data. For example,
if you cache frames 0 to 50, and then jump to frame 60, Particle flow will
calculate frame 51 based on the cached data, and frames 52 to 60 based on
each previous frame.
Start/End Time The first and last frames of the range considered for caching
when Range=Custom (see above). Default=0, 30.
NOTE The frame range time frame is in absolute time; that is, in terms of the
entire animation. If you use a Cache operator locally, and specify a frame range
during which no particles are present in the event, Particle Flow won't use the
cache.
Sampling Determines how often the Cache operator samples and caches the
animation. Default=Every Frame.
■ Every Frame The software caches animation data once per frame.
■ Integration Step The software caches animation data at each integration
step, using the Integration Step setting as specified in the Use At setting
2940 | Chapter 14 Space Warps and Particle Systems