Saves the geometry to disk with the last control settings.

Use a TOP network to cook and save the cache files to disk in a separate background process. This allows you to keep working on other parts of Houdini. The cached frames will show up as they are completed by the other process.

Stops all background caching processes, if any exist.

When this is Frame Range the node writes a cache file for every frame (see Start/End/Inc below). If you don’t want pre-generate all frames at once, or if you know you only need to regenerate a single changed frame, you can set this to Single Frame. This makes the node write out a cache file only for the current frame (or the frame you set in Override Frame).

When Evaluate As is Single Frame and the checkbox to the left is on, cache this explicit frame number instead of the current frame from the timeline.

Specifies the range of frames to render (start frame, end frame, and increment). All values may be floating point values. The range is inclusive.

These parameters determine the values of the local variables for the output driver.

When Evaluate As is Frame Range, this is the number of fractional sub-frames to divide each frame into. Caching sub-frames increases the quality of motion blur rendering for cached animated geometry. If you set Substeps greater than 1 and you've set File Path to Explicit, make sure your explicit path expression can handle fractional frames, by using $T (floating point time in seconds) or $FF (fractional frame number) instead of $F (whole frame number).

This parameter overrides the TOP scheduler for this node.

This node can apply some transformations to the layer stack before writing out files. These transformations do not affect the final composed stage, only the number of layer files generated.

When this is on, the node writes out each frame’s data to disk before cooking the LOP Network to generate the next frame of data. When this is off (the default), the node cooks the data for all frames into memory and writes out the animated files all at once. Turning on this option ensures that only a single frame worth of data is in RAM at any one time, allowing arbitrarily large USD files to be created. But saving each frame can be slightly slower, and the generated files may be larger because of the way USD files append new data to an existing file. See saving animation above.

When this option is on, this ROP can also generate separate USD files for each frame. To do this, embed the local variable for the current frame number in the Output File path (and other layer save paths) so each frame will write out files with unique names. For example:

$HIP/usd/scene_$F4.usd

See expression in filenames for more information.

When this is on (the default), the node errors if it would otherwise write an anonymous in-memory layer (that is, a layer with no file path metadata) to disk.

You will usually only turn this off if you are using Save Style ▸ Separate Layers (Preserve All Sublayers and References) to write out every layer separate for debugging purposes.

Enable this option to prevent layers authored above Layer Break nodes from being written to disk by this ROP. This allows a Layer Break node to dictate which portions of the LOP Network are to be saved. Disabling this option allows this behavior to be overridden, forcing the full stage authored by the LOP network to be written to disk. This may be used for debugging purposes, or to write a complete scene to disk for rendering.

This is automatically added by default. This processor changes absolute file paths to relative paths in layer files. This allows you to use paths such as $HIP/usd/foo.usd for loading, but have them written out as paths relative to the source file. This is recommended practice so you probably do not want to remove this processor.

The folder where all of the output files are stored.

Causes any Save Path parameter that are relative paths to be treated as if they are relative to the output file. This makes it easy to ensure all files generated by a LOP network are saved into a common root directory. Changing the save location of the output file will implicitly change the save location of all other files.

This processor includes a Search Path parameter. Each asset path is compared against the directories listed in this path. If the asset is inside one of the search paths, the asset will be referenced with a search path rather than a full path or relative path.

Normally, if you change the extension of the output file, it only affects that “top-level” output file. All other external files are written to their embedded save paths, with their embedded extension. This processor changes the extension on all paths to match the extension of the output file. This means if you change the output file to use .usda (the textual format), when this processor is active, all external USD files will also switch to .usda.

Lets you specify context options that only apply while writing out files from this node. Set the number of context options to define/override, or use the plus and minus buttons to add or remove options.

You could have two separate USD render nodes with different context options, so they would write out different USD from the same LOP network depending on uses of @contextoption references in expressions. This could be useful for wedging, or to cause the LOP network to configure the stage in ways that are not good for interactively, but should be written to disk.

For each option, the name of the option. You can reference this option in an expression using @‹name›.

For each option, the type of data stored in the option, either a floating point number of a string.

For each option, the value of the option (while this node writes out USD).

Whether the node will automatically turn on Load from Disk when you click Save to Disk or Save to Disk in Background.

When File Path is Constructed and this is on, when you click Save to Disk or Save to Disk in Background the node automatically converts the expression in Base Name to a literal string. This prevents the cache from breaking if you duplicate or rename the scene file or node.

When writing out cache files, automatically create any intermediate directories in the file path that don’t exist.

A percentage complete value is printed out as files are written. This is in the style expected by Pixar’s Alfred render queue.

When saving more than one frame, save in a background thread. This can make saving faster for large file sizes, but may use more memory since it will retain the output geometry until the save completes.

If saving the geometry to disk fails due to a disk writing error, Houdini will usually error the output node immediately. This is desirable for most cases where a failure to save means an illegal path, which is not recoverable. However, sometimes files fail to save due to network issues. If the number of save retries is non-zero, Houdini will re-attempt to save this number of times. Each time will be accompanied with an output to the console of the failure to save and a five second wait in the hopes that the network will clear up.

Uses the settings in a particular take while rendering. Choose Current to use the current take when rendering.

This is what the node should do (in Load from Disk mode) when the node can’t find (or cleanly load) a cache file. Report Error sets an error on the node, preventing the rest of the network from cooking. This makes it obvious when a problem happens. No Geometry (the default) sets a warning on the node rather than an error, and outputs empty geometry. This can be useful if your network has a way of dealing with missing cache frames, or if they're not important.

If loading the geometry from disk fails due to a disk writing error, Houdini will usually error the output node immediately. This is desirable for most cases where a failure to load means an illegal path, which is not recoverable. However, sometimes files fail to load due to network issues. If the number of Load Retries is non-zero, Houdini will re-attempt to load this number of times. Each time will be accompanied with an output to the console of the failure to load and a five second wait in the hopes that the network will clear up.

Attempt to predict the next frame that will be needed and load it in the background. This lets computation be overlapped with file IO.

If you are blending multiple frames, the Cache Frames needs to be large enough for only the net-new frame to be loaded each cook. Otherwise the simple predictive model of the prefetcher will be confused and stop working.

Run this script before any rendering.

Run this script before each frame.

Run this script after each frame.

Run this script after all rendering.

Contains an expression that generates the “version” part of the path, including a v prefix. Do not edit this expression.

Contains an expression that generates the parent directory path for cache files. Do not edit this expression.

Contains an expression that generates the filename for cache files. Do not edit this expression.

Contains an expression that generates the descriptive text displayed next to this node (below the name and badges) in the network editor. This is set to output the cache filename pattern. Do not edit this expression.

Contains an expression that generates the resolved, full path of the cache file for the current frame. Do not edit this expression.