Greetings,

I am transitioning to Houdini Indie from C4D Studio, and have a couple of questions regarding information between nodes. This is based on a problem I ran into with the Polyextrude node:

- I have a line running through a wire sim.
- Using the reimported sim geo, I can sweep along the line using the Sweep node successfully.
- Using the exact same info, attempting a polyextrude in “use external curve” mode will not work. It seems to ignore the line?

My conclusion this far is that the Polyextrude node expects a curve, not a line (which AFAIK is just a list of points). I have attempted to construct a curve using the point info, but it does not seem to help.

So, questions:
1. In the above case, what should I be doing to get Polyextrude to accept the incoming data as the desired curve?

2. In general, how can I tell what kind of input a node port expects, and what is being output from a node? I feel as if I am sometimes blind now as I do not really know what to pipe into certain nodes.

Many thanks in advance!

You may want to drop down a Convert node right after your line but before it connects into the PolyExtrude. The convert node allows you to switch geometry type from one type to another. Check the help card for PolyExtrude and make sure you are giving it the correct input.

If all you have are points, drop down an Add node and use the second TAB to connect the points to form a line.

Thank you for the reply!
I managed to figure it out, and part of my problem was me momentarily ignoring the obvious: The polyextrude node obviously does extrude from the face, whereas the sweep will give base the geometry on the curve position and cross section. Apologies for that.

But regarding the second question:
Is there a way in the UI to tell what input a node is expecting? In the case of the help card for the polyextrude, it merely states “a curve”, which is quite broad.
Can one safely assume that the correct input is being provided if there is no error associated with the node?

In short, I would like to be able to debug my network if it does not behave as I expect it to.

Many thanks in advance!