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This function outlines the process for adding a geo node to the object network and formatting some of its display settings. The same process can be applied to nodes in other networks and can be a utility for the 123.py and 456.py startup files to automate its creation upon loading Houdini.

Reference: https://www.sidefx.com/docs/houdini/network/organize.html#bulk-changes

Using the available options noted in the list Node Shapes, the following snippet can be used to set a node's shape.

Network Box Comment

Network boxes have a field at the top of each where a string can be input to serve as a title; this is noted as the network box's 'Comment'. Multiple network boxes can have the same 'Comment' without issue.

Network Box Name

However, at the same time, each network box has a unique identifier as noted by its 'Name'. With Python, the createNetworkBox() method includes an argument to specify the unique name for each network box.

The value applied to this 'Name' is not visible from the network view, but can be called with Python using the following:

which then returns the following:

Get and set default colors for Houdini sticky notes, text, and network boxes. Default Houdini color codes are outlined in the following list: Default Node Colors.

References:

The Group SOP can use this script to set the group name to the name of the node, which mitigates the need to set the group name parameter within the SOP and the SOP name itself. Ultimately, this aligns the name of the node with the group name and can help with keeping group names organized.

This script is intended to add custom parameters and folder organization to nodes for relaying parametric data to other nodes in the network, such as a control panel for an HDA.

Method for setting parameter values with specified data type or expressions.

Clarification of the available operations that can be applied to a menu parameter.

Python Module code requires the HDA naming to be specified as PythonModule.

Reference: https://www.sidefx.com/docs/houdini/hom/hou/HDAModule.html

The script above returns the following output based on the type of matcher.

Query By Name

Composite Query: By Name & Type

Python snippet for use in Houdini to rename a primitive attribute string value.

Callbacks are triggered by user-specified parameter value changes or via the parm.pressButton() function. For instance, the following links the color parameter select with the node color using a Python script callback.

In the case of an HDA created inside of a GEO node, the following function is created within the Python Module event handler:

Meanwhile, the following call to the function above is made in the On Created event handler within the same HDA:

The output notes how each of the event handlers recognizes the corresponding node when the function is called from the On Created event. It reflects the HDA as the node while the Python Module recognizes the parent node, geo, as the node.

kwargs global dictionary variable.

Utilizing kwargs to get node and parameter information can be coordinated with the node's Python Module and individual callback scripts for each parameter.

Output when the string parameter is triggered:

Output when the integer vector parameter is triggered:

Output when each of the multiparm instances are triggered:

Reference: https://www.sidefx.com/docs/houdini16.0/hom/tool_script#arguments

Using the hou.ui module, the following are some opportunities to provide user feedback in the form of a dialog box with interactive buttons.

Custom Confirmation

Add a string parameter to the selected node and enable the following options:

The following collects all of the above and collects them into a script to add the Python panel to selected nodes.

Upon starting up Houdini, the 123.py startup script file is configured in Python to automate the creation of several nodes and specific settings in the obj, mat, and out networks. This includes the configuration of relevant parameter settings, all with the intent of being able to quickly start a project file consistently and with a basic project management structure.

Edit UI preferences for a Network Editor pane in a Houdini desktop/session via Python. Available preferences are noted in the following list Editor Preferences.

This enables the realtime playback toggle on Houdini playbar. It can be integrated within the startup script to have it enabled when Houdini is opened.

Resources

These images capture some of the aspects that the workspace automation script addresses, namely the creation, formatting, and placement of nodes in the applicable networks: obj (Fig. 1), mat (Fig. 2), and out (Fig. 3). Other setup operations include configuring light and camera placements in the scene, material setups within each of the RS Material Builder nodes, and Redshift ROP node settings.

Setup PyCharm to be the external editor for Houdini by specifying it in the Houdini Environment file as follows:

Accessing Windows > External Python Source Editor will open a Python file in PyCharm titled __python_source_editor.py that can be used to input Python for use in the current Houdini session.

hython.exe location: $HFS/bin

In PyCharm, add the following paths to the Interpreter's Paths collection:

Note that the file may be capped by PyCharm's file size limit, but if encountered, can be resolved with this resolution.

To autocomplete the Houdini library, set the following path as a Resource in the Project Structure:

Classes appended with _swigregister are included in the list simply because the hou module is constructed with swig.

hou.session is stored in the .hip file

Available under the Windows menu

Functions defined here are stored in the hou.session module

Reference the following section for an example of applying Python States in HDAs.

Function defined in PythonModule (Edit Operator Type Properties > Scripts > Event Handler > Python Module) can be accessed in Python using hdaModule()

hou.node("/obj/hda_node").hdaModule().functionName()

External .py files can be added to HDA in this Scripts section via Add File.

Guide for installing additional libraries:

Source: https://wordpress.discretization.de/houdini/home/advanced-2/installing-and-using-scipy-in-houdini/

Viewport Color Schemes Location:

List of schemes:

Ref: https://www.sidefx.com/docs/houdini/hom/hou/viewportColorScheme.html

The following RGB values are for the default node colors available in the Color Palette for use in the Network View. The palette can be accessed with the C keyboard shortcut. These RGB values can be used with hou.Color(), as shown above in Create & Format Node.

This is used access the available list of node shapes under the Shape Palette for use in the Network View. The shapes can be accessed by way of the Z keyboard shortcut.

List of available UI preferences for a Network Editor pane in a Houdini desktop/session.

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