Make Your Own Tools

The core nodes are made to be combined. A recipe you build, a few Grow steps in a Repeat block with a Switch between alternatives, is already a reusable piece. Wrap it in a Houdini Digital Asset and it becomes your own tool, one you can reuse across scenes and hand to other artists.

The shipped nodes are built this way. Grow is not atomic; it is split, switch and repeat given an artist-facing interface. You can do the same: name your tool for the organ or behaviour it models, and expose only the parameters that matter. Simulation covers the grammar these recipes are built from.

To make your tool behave like the shipped nodes, give it the same kinds of parameters with Mapping Template (experimental) and Effector Template. Both are hidden from the Tab menu in 0.7.3 and are not on the toolbar. To place them, open Windows > Hscript Textport and run:

opunhide Sop natsura::mapping_template::1.0
opunhide Sop natsura::effector_template::1.0

They then show in the Tab menu until you restart Houdini. Put them inside your HDA; Target HDA points at the node they sit in by default.

Mapping Template adds mappable parameters to your HDA. List the parameters under Mappable Parameters and click Promote to Target. They get the same map button as the shipped nodes. Effector Template adds an effector stack the same way, so artists can add effectors to your tool. On both, New Maps Read From sets whether a map made from these parameters starts reading Self or Parent; decorations use Parent.

Both templates contain example code. VEX covers writing your own effectors and maps to go with them.

Status

A full walkthrough, covering what to promote, how to keep the tool compiling, and the conventions for a Natsura tool, is still to come.