Houdini 18.0 Nodes TOP nodes

Error TOP node

Create warnings or errors when a condition is met

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This node passes input work items through unchanged, and can optionally report a node warning, node error or work item error. If this node is inside a subnet or digital asset, the error messages will also be displayed on that asset. You can use this node to report errors or warnings to the user of an asset, for example to indicate that a parameter value is invalid.

Errors are reported when their Report Error When expression evaluates to 1, otherwise the error is not reported. The expression can refer to workitem attributes.

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If Error Type is set to Work Item Error, this attribute is created and set to the Error Message value for all work items that have an error.



If Error Type is set to Work Item Error, this attribute is created and set to 1 for all work items that have an error.


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.

Evaluate Errors During

This parameter controls when the node evluates the error conditions and produces messages.

Number of Errors

The number of error conditions to evaluate.

Error Type

The type of message to produce. This can either be a node error, a node warning or a work item error.

Node errors will cause the node to stop evaluating. If you want to provide the user with information without stopping graph evaluation, you should set Error Type to Node Warning instead.

Error Message

The error message to report.

Report Error When

If this expression evaluates to a non-zero value the node will report the error/warning message.

See also

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