Hey there,
It’s Robin from CFD Engine & I’ve got a possible ParaView pipeline proxy for you this week (& by proxy I mean alternative, but that doesn’t start with “P”) 😉
I hadn’t appreciated that some people struggle with (or just don’t like) building pipelines in ParaView. Defining a scene by stringing together (in a specific order) a bunch of (sometimes oddly-named) filters & sources just isn’t for everyone.
It’s not better or worse, it’s just different. But if you’re not in ParaView all that often, then I can imagine that it could feel a bit alien.
Well, if you thought the traditional pipeline was different, you may want to look away now 🙈 There’s a new plugin that offers an alternative way to manage your pipeline – checkout ParaView’s new node editor.
Node Editor?
Some call it a node editor, some call it a network editor, whatever you call it, it’s essentially a super-powered, flow chart view of your pipeline.
But let’s show, not tell…
Here’s a terrible plot of some streamlines released from a grid upstream of our favourite CFD motorBike and the pipeline used to produce it (click for the bigger version):
And here’s the same pipeline in the new node-based editor (click for bigger version):
Each source (or filter) is represented by a node showing its settings, whilst the lines show how they’re interconnected to produce that incredible final image.
The two views (the traditional pipeline & the nodes) are equivalent, but the nodes are arguably more intuitive & definitely more informative.
In it’s current state, the node editor is best suited to tweaking & visualising your pipeline. You can alter connections, change settings, turn things on & off etc, but I’d still probably build the pipeline in the conventional way.
As the tool evolves that might not be necessary, you might be able to do away with the pipeline view altogether & just use nodes.
Many popular visual effects & video editing tools like Unity, Blender & DaVinci Resolve lean heavily on their node-based editors. Similarly, Grasshopper brings a node-based workflow to parametric/algorithmic geometry creation.
Perhaps this is where we’ll end up with ParaView?
Bothered?
Whilst ParaView’s node-editor is not quite there yet, it’s already pretty useful. In particular, I think it offers a great way to document complex pipelines.
An image, like the one above, tells you almost everything you need to know to re-create the scene, all in one image. A collection of these images describing your standard post-pro techniques, posted on an internal wiki, would be a great reference for any team.
Similarly, they could also be a useful teaching resource, an intuitive way to demonstrate how filters & sources can be combined to produce a given output.
You could do both of the above with state files or Python scripts, but this seems like a visually appealing & instructive alternative.
Have a go
If you want to take it for a spin, you’ll need to grab a recent nightly build from the ParaView website.
Once installed, go to Manage Plugins in the Tools menu, find the Node Editor in the list & load it in.
This will pop up the “graph paper” view where your nodes will be displayed (I think it works better if you undock this view & make the canvas larger, especially for more complex pipelines).
It has a few kinks that need working out, for example zooming in & out can make the nodes look a bit off. But overall there’s enough here to play with, to give you a taste of what’s to come & to see whether it might be useful for you.
Check out the announcement blog post for more info & the plugin readme for some tips on how to drive it.
What do you reckon?
I’m already thinking about how I could use this to share ParaView tips – do you think it could be useful in your ParaView workflow?
Let me know, I’m keen to hear your thoughts.
Similarly, let me know if there’s something about ParaView you find tricky, it might make a good subject for a future email 🙏
Until next week, stay safe,
