Over the years there has been more than a few changes with the features in Houdini, and how things are done. Most recently with the release of Houdini 15, there were some changes to controlling the PolyExtrude node.
Using the new Polyextrude and using attributes to control the extrude amount.
No longer can you directly use variables to control the extrusion amount of the extrude node, but there is another way. Here, Rohan Dalvi shows that you can easily generate attributes, and then use those attributes to control the extruded values from Houdini 15’s PolyExtrude function.
Houdini 15 has moved aways from using local variables for things, to using attributes instead. Rohan believes that this is where Side Effects will be headed as the preferred method for working, rather than using local variables.
