Houdini 18.0 Nodes TOP nodes

Filter by Range TOP node

Filter upstream work items that fall within a specified frame or attribute range

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This node is a specialized version of the Filter by Expression. It can be used to filter out work items that are inside or outside of a specified range. You can choose whether the work items should be matched using their frame value, index or a custom numeric attribute value.

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If the Set Range Attribute parameter is enabled, the node will write the range values to a float attribute on each work item. This attribute is useful when you're using this node to select a subset of frames from a ROP Fetch, which also adds a range attribute to work items. Other downstream ROP Fetch nodes that are operating in batch mode expect to use that range attribute in order when creating batches.


Work Item Generation

Whether this node generates static or dynamic work items. You should generally leave this set to "Automatic" unless you know the node’s work items can be computed statically, or that they need to be generated dynamically.


This node always creates dynamic work items: it waits until the upstream work items are known, and generates new work items from the upstream work items.


This node always creates static work items: it creates the number of work items it thinks it needs based on the parameters (and any upstream static items) before the network runs.


If the input is static (a static processor, or a partitioner with only static inputs, or a mapper), this node generates static work items, otherwise it generates dynamic work items.



Determines whether the node should keep work items that fall within the Filter Range or if it should discard work items in the range.

Filter Using

Determines which work item attribute to compare against the Filter Range.


The node uses the work item’s frame value to determine if it’s included in the range


The node uses the work item’s index value to determine if it’s included in the range

Custom Attribute

The node uses a custom attribute, which you specify using the Custom Attribute parameter. This attribute must be numeric (either a float or integer) to work correctly, since the Filter Range is specified numerically.

Custom Attribute

When Filter Using is set to Custom Attribute, you can use this parameter to indicate the name of the attribute to use when checking if the work item falls within the Filter Range.

Filter Range

The start and end value for the range. These values are inclusive, so if the range goes from 1 to 10 a work item with a frame value of 10 will be inside the range.


Set Range Attribute

When this parameter is enabled, the node will write the Filter Range into an attribute on the work items. This is useful when using this node to select a subset of work items produced by a ROP Fetch node, which also writes a range attribute onto its work items. Other ROP Fetch nodes operating in batch mode use that attribute to generate batches, so if you plan to use the filtered items with a ROP Fetch you should enable this parameter.

This functionality is currently only available when Filter Using is set to Keep Items in Filter Range.

Include Output Files

When this toggle is enabled the output file lists on the filtered work items are preserved.

See also

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