Houdini 17.5 Nodes TOP nodes

Generic Generator TOP node

Generates work items with no attributes that run a command line.

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You can use this to generate work items with a command line generated by an expression. It can also sometimes be useful when starting a network to simply generate a certain number of work items that don’t do anything (leave the command line blank), so you can add attributes to them and use them to drive downstream nodes.

If you want more advanced functionality, use a Python Processor instead.

This node will generate Item Count work items when it has no inputs, otherwise it will generate Item Count work items for each upstream work item.

Parameters

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.

Dynamic

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.

Static

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.

Automatic

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.

Sequential

Makes each generated work item will depend on the previous one, so they run in sequence instead of simultaneously.

Item Count

The number of outgoing work items to generate for each incoming work item. If there are no incoming work items, the node generates this number of outgoing work items.

Index

By default, the node gives the generated work items sequential index attributes starting at 0. If you want to generate custom index values from an expression, turn this on and enter the expression in the text field.

Frame

By default, the generated work items inherit the frame attribute from the corresponding incoming work item. If you want to generate custom frame values from an expression, turn this on and enter the expression in the text field.

Priority

By default work items will be assigned a priority of 0. If you want to set a custom priority, turn this on and enter a number or expression in the text field. Items with high priority values run before items with low priority values.

Delay Time

Turn this on to have each work item wait for a certain number of seconds instead of running the command line (when this is on, the Command parameter is disabled). This is sometimes useful for simulating a slow workload to see how it affects the rest of the network, for example to check whether nodes correctly wait for results before proceeding.

Command

The command line (executable and arguments) to run when the work item runs. If this field is empty the work item will not be scheduled, and will be instantly marked done once all of its dependencies finish.

Examples

example_top_genericgenerator Example for Generic Generator TOP node

This example demonstrates how to use generic generators to both prototype setups and to run custom command line executables.

The following examples include this node.

example_top_attributecopy Example for Attribute Copy TOP node

This example demonstrates how to copy attributes from one workitem to another.

example_top_attributecreate Example for Attribute Create TOP node

This example demonstrates how to create attributes for workitems of TOP nodes.

example_top_attributedelete Example for Attribute Delete TOP node

This example demonstrates how to delete attributes for workitems of TOP nodes.

example_top_attributefromstring Example for Attribute from String TOP node

This example demonstrates how to create attributes for workitems from a piece of string attribute coming from upstream.

example_top_csvoutput Example for CSV Output TOP node

This example demonstrates how to create a csv file from pdg work item’s attributes.

example_top_errorhandler Example for Error Handler TOP node

This example demonstrates how to use the Error Handler node in PDG / TOPs.

example_top_feedbackend Example for Block End Feedback TOP node

This example demonstrates how to create a feedback loop.

example_top_filterbyexpression Example for Filter By Expression TOP node

This example demonstrates how to filter upstream workitems so that the remaining set can be further processed or debugged.

example_top_forloopwithfeedback

This example demonstrates how to use the for loop with feedback construct in PDG/TOPs.

example_top_genericgenerator Example for Generic Generator TOP node

This example demonstrates how to use generic generators to both prototype setups and to run custom command line executables.

example_top_makedir Example for Make Directory TOP node

This example demonstrates how to use Make Dir to create directories on the system.

example_top_mapall Example for Map All TOP node

This example demonstrates how to use the Map All node to establish dependencies from everything downstream to everything upstream.

example_top_mapbyindex Example for Map by Index TOP node

This example demonstrates how to use the Map by Index node to establish dependencies from downstream to upstream based on workitem index.

example_top_mapbyrange Example for Map by Range TOP node

This example demonstrates how to use the Map by Range node to establish dependencies from downstream to upstream based on workitem index.

example_top_merge Example for Merge TOP node

This example demonstrates how to use the merge node in PDG/TOPs.

example_top_null Example for Null TOP node

This example demonstrates the usage of null nodes.

example_top_partitionall

This example demonstrates how to use the partition all node in PDG/TOPs.

example_top_partitionbyattribute Example for Partition by Attribute TOP node

This example demonstrates how to use the partition by attribute node in PDG/TOPs.

example_top_partitionbycombination Example for Partition by Combination TOP node

This example demonstrates how to use the partition by combination node in PDG/TOPs.

example_top_partitionbycomparison Example for Partition by Comparison TOP node

This example demonstrates how to use the partition by combination node in PDG/TOPs.

example_top_partitionbyexpression Example for Partition by Expression TOP node

This example demonstrates how to use the partition by expression node in PDG/TOPs.

example_top_partitionbyframe Example for Partition by Frame TOP node

This example demonstrates how to use the partition by frame node in PDG/TOPs.

example_top_partitionbyindex Example for Partition by Index TOP node

This example demonstrates how to use the partition by index node in PDG/TOPs.

example_top_partitionbynode Example for Partition by Node TOP node

This example demonstrates how to use the partition by node in PDG/TOPs.

example_top_partitionbyrange Example for Partition by Range TOP node

This example demonstrates the multiple partition options provided by the partition by range node.

example_top_perforce Example for Perforce TOP node

This example demonstrates how to perform multiple perforce operations.

example_top_pythonmapper Example for Python Mapper TOP node

This example demonstrates how to use the Python Mapper node in PDG/TOPs.

example_top_pythonpartitioner Example for Python Partitioner TOP node

This example demonstrates how to use the Python Partitioner node in PDG/TOPs.

example_top_pythonprocessor Example for Python Processor TOP node

This example demonstrates how to use the python processor in PDG/TOPs.

example_top_pythonscript Example for Python Script TOP node

This example demonstrates how to use the Python Script node in PDG/TOPs.

example_top_sort Example for Sort TOP node

This example demonstrates how to use the sort node in PDG/TOPs.

example_top_split Example for Split TOP node

This example demonstrates how to use the split node in PDG/TOPs.

example_top_switch Example for Switch TOP node

This example demonstrates how to use the switch node in PDG/TOPs.

example_top_topfetch Example for TOP Fetch TOP node

This example demonstrates how to use Top Fetch to fetch results from other top networks.

example_top_topfetchinput Example for TOP Fetch Input TOP node

This example demonstrates how to use Top Fetch to fetch results from other top networks (using Top Fetch Input).

example_top_workitemexpand Example for Work Item Expand TOP node

This example demonstrates how to use the workitem expand node in PDG/TOPs.

See also

TOP nodes