Create or import nCaches

User Guide > Dynamics and Effects > nDynamics > nCaching >

Note

nCloth caches only store information about the XYZ positions of an nCloth object’s vertices, not the translation, rotation, or scale of the nCloth’s Transform node.
nCloth caches are dependent on their nCloth’s Space Output (Local or World).
You can select the nParticle attributes you want to cache in the Caching section of the nParticleShape node Attribute Editor. See Caching.

You can create single or multiple nCaches for your Nucleus objects or fluid effects, each of which can be comprised of a single frame, multiple frames, or a range of frames. If you create more than one nCache for a Nucleus object or fluid effect, you can then blend its caches to create new simulations and effects. See Blend and set the weighting of nCaches from the Attribute Editor.

In addition to creating new nCaches, you can also import nCaches that you have previously created. Importing nCaches will not override or replace any existing cache data attached to your objects.

To create a new nCache

Select the Nucleus or fluid object(s) for which you want to create an nCache.
Depending on the type of object you are nCaching, do one of the following:
- For Nucleus objects (nCloth and nParticle objects), in the nDynamics menu set, select nCache > Create New Cache.
- For Fluid objects, in the Dynamics menu set, select Fluid nCache > Create New Cache.

(Optional) If an nCache file with the same name already exists in the directory specified in the Create nCache Options or Create Fluid Cache Options window, the Create Cache Warning message appears.

Do one of the following:

Click Rename to change the name of the cache you want to create. The Create nCache Options or Create Fluid Cache Options window appears. Type a new name for the new cache in the Cache Name field and click Create. See nCache > Create New Cache or Fluid nCache > Create New Cache.
Click Auto-rename to create a new nCache file. The new cache file is saved to a new folder on disk, the object’s current nCache file is detached from its cache node, and the new nCache file is attached to the object’s cache node.
Click Cancel to exit the Create New Cache operation.
Click Replace Existing to create a new nCache file. The object’s current nCache file on disk is replaced with the new nCache file, and the new nCache file is attached to the object’s cache node.

Your objects’ simulations are cached using the Create nCache Options or Create Fluid Cache Options window’s current settings. See nCache > Create New Cache or Fluid nCache > Create New Cache.

Single or multiple .mc cache files and an .xml description file are generated and stored in the directory you specified in the Create nCache Options or Fluid Cache Options window. cacheFile nodes (named nObjectShape#Cache# by default) are also added to your objects, and any existing nCache nodes are disabled so that you can see only the new caches playback.

NoteWhen an nCache exceeds the 2GB cache size limit, it is automatically split and the resulting cache segments are blended.

If you selected a single object, the following files are created:

File Distribution	# of nCache files created	# of XML description files created	# of nCache nodes created
One File	1	1	1
One File Per Frame	Multiple, 1 for each frame	1	1

If you selected multiple nCloth objects, the following files are created:

File Distribution	# of nCache files created	# of XML description files created	# of nCache nodes created
One File	1	1	Multiple, one for each object
One File Per Frame	Multiple, one for each frame	1	Multiple, one for each object
One File and One File per Geometry	Multiple, one for each object	Multiple, one for each object	Multiple, one for each object
One File Per Frame and One File per Geometry	Multiple, one for each frame, for each object	Multiple, one for each object	Multiple, one for each object

TipWhen caching a number of Nucleus objects that are part of a single Maya Nucleus system, disable the system’s Maya Nucleus solver to avoid playback slow downs.

To import an nCache

Select the object for which you want to import an existing nCache from disk.
Depending on the type of object for which you are importing an nCache, do one of the following:
- For Nucleus objects, in the nDynamics menu set, select nCache > Attach Existing Cache File.
- For fluid objects, in the Dynamics menu set, select Fluid nCache > Attach Existing Cache File.
The Import file browser window appears. See either nCache > Attach Existing Cache File or Fluid nCache > Attach Existing Cache File.
Navigate to the nCache file(s) you want to use for your object and do one of the following:
- For a single nCache file, select either the .mc cache file or the .xml description file for the One File cache you want to import to the current object.
- For multiple nCache files, select the .xml description file for the One File Per Frame cache files you want to import to the current object.
  NoteThe nCache you want to import must have been generated from the same topology as the selected object.
Click Import.
A new cacheFile node is created for the imported nCache and it is automatically attached to the selected object’s cacheBlend node. This allows you to combine the imported cache with any of the selected object’s existing nCaches.