Houdini 19.5 How to use the help

Creating custom examples

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This page explains how to create your own node example files and integrate them with the documentation when you are running a custom help server.

How to

To create an example file:

  1. Encapsulate your example inside an object level asset, and save it to an HDA file. The HDA file should only contain one object-level asset.


    Include and reference any support files (.bgeo, .pic, etc.) needed by your example as sections in the HDA file.

  2. Create a .txt file containing a description of the example, using wiki formating. Give it the same name as the .hda file except for the extension. For example, MyNodeExample.hda and MyNodeExample.txt.

  3. Place the files somewhere in the Houdini path in:


    For example:


Wiki properties

In the text file describing the example, you can use page properties to control how the server finds the example.

  • If the text (.txt) file is not named the same as the example (.hda) file for some reason, you can use a page property to point to the example file:

    #examplefile: example.hda

    The path can be absolute (start with a /) or relative to the text file.

  • If you put an example file in HOUDINIPATH/Help/examples/nodes/nodetype/nodename/, the serve automatically associates the example with that node type.

    If you want to associate an example with more than one node type, or put it somewhere else for some reason, you can manually specify a space-separated list of node paths to associate the example with:

    #examplefor: /nodes/sop/MyAsset /nodes/dop/HerAsset


You can use loader markup to create buttons in help pages to load example files.


The Copy SOP can be used for more than copying geometry. In this example, the Copy SOP is used to transfer color attributes from the template geometry (or point) to the copied geometry.

A polygonal sphere with color infomation is used as the source geometry. A point with a color attribute (Cd) is extracted from the sphere and used as a template by the Copy SOP. Then the Copy SOP transfers the color infomation to a copied polygonal circle.

Individual loader

A load_example block will display a loader for a single Houdini node example.

:load_example: Copy Attributes example
    #examplefile: /examples/nodes/sop/copy/CopyAttributes.otl
    #examplefor: /nodes/sop/copy
  • You can omit the #examplefor property.

  • If you specify a #path: property pointing to the example’s description (.txt) page, you can omit the title, #examplefile, and #examplefor. The help system will fill them in from the referenced page.

        #path: /examples/nodes/sop/copy/CopyAttributes
  • Add an #include: yes property to automatically include the contents of the page referenced in #path to the loader:

        #path: /examples/nodes/sop/copy/CopyAttributes
        #include: yes

    This is the same as:

        #path: /examples/nodes/sop/copy/CopyAttributes
        :include /examples/nodes/sop/copy/CopyAttributes:

    The help system automatically strips the title and summary when it includes in a load_example block.

Example list

A list_examples block is like a search list block but displays the results as example loaders.

    #query: path:/examples/nodes/sop/*
    #groupedby: examplefor

How to use the help


Documenting nodes

Running a central help server