I'm learning command-line rendering through Python, but I can't get RopNode to work. When I use hou.RopNode.render() I get “unbound method render() must be called with RopNode instance as first argument (got nothing instead)”. When I try to add “mantra1” in the parentheses (the file I want to render is the one open) I get the same error except “got str instance instead” in the parentheses. For all my Googling I haven't found any examples of how to successfully use this. What am I missing?

The node classes don't have constructors. You need to get an instance from a node directly.

something like this:

That gives me “AttributeError: ‘NoneType’ object has no attribute ‘render’”.

JMR
That gives me “AttributeError: ‘NoneType’ object has no attribute ‘render’”.

Then the path given to hou.node() doesn't exist. node() takes a path to a node. Try dragging the node you want to render to the console. The dropped item will contain the actual path.

That means the node the path references doesn't exist, or it's not a ROP node. Make sure the path to your ROP is correct.

Progress. Now the message I get is:
<bound method RopNode.render of <hou.RopNode of type ifd at /out/mantra1>>

I am using Houdini NC on a Mac, if that makes a difference.

Thanks!