Caching

Compositing
1

Just getting started so hoping this isn't too newbie of a question:

I've played around with both the cache node and Shift-playing to cache playback in the viewer. I just can't seem to get the hang of things. For example, when doing roto and scrubbing through playback, is there anyway to force the viewer to cache the sequence so that there isn't a second or two pause as each frame is loaded (working at HD). In fusion, when you work through a part of a shot, the frames are cached for real time playback of that portion you are working on -- obviously until you make a change that demands a rerender. With Shake, it seems like no matter what I do there is a 1 to 2 second pause as the program loads frames? Is this a hardware issue -- powerbook 1.5ghz 2gig ram -- or is it just a limitation in the program. How does everyone else do quick, smooth roto?

j

2

check your cache mode mode options under the render globals of your script. they should be set to regular.
also, check your startup.h file for something called diskCache.cacheMaxFileSize and diskCache.cacheSize, they might be set wrong.

3

I don't actually have a startup.h file in my startup directory. Can you send me the proper settings for diskCache.cacheMaxFileSize and diskCache.cacheSize -- I'll try making my own. Must be somewhere where Shake is told how much memory it can use, etc?

j

4

right the file goes in your HOME/nreal/include/startup/

shake scans this directory on startup and will load any custom settings from it.
its a plain text file, use text edit or VI, plain text files only mind, no rich text. Call it whatever you want as long as it has a .h extension, startup.h or memory.h, you can have multiple files if you want.
the three lines you'll be adding are:

cache.cacheMemory = 96;
diskCache.cacheMaxFileSize = 2048*2048*4*2;
diskCache.cacheSize = 512;
diskCache.cacheMemory = 500;

you want to up the disk cache size and memory parameters to suit, and yes they are case sensitive.

you can also edit these values in the nreal.h file in your Applications/Shake/Shake.app/Contents/Resources but be very carefull, you don't want to screw up this file. If you do, it's a re-install if you don't have a backup.

if you do get stuck, take a look under the "tunning the amount of RAM shake uses" section in the manual, that should sort you out.

5

Thanks so much. Will make a new file called memory.h and add the suggested lines. Will look at the manual about tuning RAM -- assuming that explains what these variables mean and the ramifications for increasing or descreasing a particular size -- I have 2 g ram and want to use as absolutely much as possible for caching.

BTW -- I've found that shift-playing to load as much of the sequence into ram works quite well. Also found that if you make a small change in the middle of the cached frames, you have to recache everything...

j