Who here is professionally using Phi Freeform Modeler?

EvanReese

I still love the idea of an Onshape-integrated freeform tool, and I respect that Phi is trying something new and not just doing a me-too Sub-D tool. I'm semi-keeping up with their updates and it seems like they've come a long way since I beta tested way back when (at the time it was interesting, but I couldn't picture where I'd prefer it to standard surfacing tools). I'm still curious to hear an account from someone who has actually integrated it into their workflow. Does anyone have an experience they'd like to share with the class? Pros, cons, tips, anecdotes, etc.

S1mon

I tried Phi out a while back, and I continue to follow it, and found a few issues:

1. The surfacing quality was not where I would want it to be. Yes, you could very quickly create swoopy surfaces, and there are some unique tools, but overall is it something that would compete with Rhino, Alias, ISDX, CATIA, NX or ICEM - no. It might be good for form finding, but it's not a Class-A surfacing tool as far as I could tell. The latest update promotes that they've updated the underlying math to improve the curve quality, but the demo still clearly shows that they are G2 not G3. If there are better ways to keep things G3, they need much better demos - I see the curvature plot below, and I'm done - I would not touch this.
2. The smoothing technology is interesting, but it often does things which I would never want. 
3. The yearly cost is not that different from a seat of Rhino - which is orders of magnitude more powerful, although it's not integrated or cloud based. But then Phi is only so integrated. It's contained within the Onshape document, but it still uses the concept of saving and auto backups - not microversions.
4. While I see a certain amount of development as evidenced by the releases, it seems like it's so niche that I question if it will be around in the future. Their YouTube page has 65 subscribers. Not thousands, sixty-five. Rhino has 24.2k, Shapr3D has 141k, and Nick Kallen who's developing Plasticity - which is almost out of beta - has 4.26k. Phi needs a lot more users and/or much much better demos.

S1mon

Further examples:

Phi concept car demo: https://www.youtube.com/watch?v=EC06ZiqODMA



Here's a Plasticity beta user doing car modeling:
https://www.youtube.com/watch?v=lNMbxNc5BOk



Plasticity has G3 Blend curves, and can do freeform 3D control point editing of curves, but the surfacing tools still have very basic controls. The surfacing shown here is definitely not Class-A, but seeing the workflow is impressive (I believe this person is in the gaming industry, not CAID). I'm sure much better work could be done in Phi than shown above, but the demos are dreadfully basic. Who would ever show automotive design CAD not in perspective?

Personally, if I really needed to do high end surfacing that I couldn't manage to do directly in Onshape, I would likely get a seat of Rhino. Rhino is also a bit of a Swiss army knife that has a tool for everything, even if it's not perfect. Sometimes you need something to flatten a 3D surface, or make some crazy pattern.

I already paid for Plasticity because it's so inexpensive, and the trajectory of development has been impressive, but until it gets to a 2.0 release I probably won't do much more than play with it. Plasticity 2.0 should bring things like lofts that update when you change the driving curves, and possibly editing of the CVs in the middles of surfaces. Right now it doesn't even have curvature combs, so I can only do so much real work with it (it does have zebras and nice HDRI shaders, but no curvature combs!). It is based on Parasolid, so there are opportunities to edit/create things that I know will translate back and forth to Onshape perfectly.

Nick_Holzem

Following. I've poked around with Phi in the past. Would love to see Phi be more useful.

MichaelPascoe

Phi by itself works really well, but not with Onshape. I've tested multiple times, even after recent updates, on simple and complex models and have been in contact with their team. It is unable to convert Onshape models of any complexity except almost primitive shapes. This challenge must have proved to be too difficult for them, they seemed to have moved on.

S1mon

@MichaelPascoe
Wow. Somehow I had missed that little detail. That would be a show-stopper for most professional users.

I wish that Plasticity would be tied into Onshape. Since it's Parasolid based, there are no issues with geometry passing back and forth, but all history and parametric stuff is lost. 

stephanos_androutsellis_theotokis

Hi all,

I'm one of the Phi developers and I read the above comments, which make sense to me, but I'd like to give a little more perspective. Firstly thank you for checking out Phi, regardless of the impression it left on you, it's always good to see experienced designers getting involved.

So regarding importing models from Onshape into Phi, here's the deal. Phi is a completely different surface modeler, it has its own representation, maths, etc.  As a result, it's not possible to always get any model from some other solid modeler and exactly replicate it into Phi. If you think about it, the same is true for sub-D, for example, for just the same reason: You can't get any model and re-create it precisely based on sub-D maths. The way it works and the requirements are very different.

Having said that, we are indeed integrated within the Onshape platform, and we appreciate that a user would expect to be able to send their work back-and-forth between Onshape and Phi. Good news is that anything you create in Phi can be exactly converted into an Onshape Part Studio, with the press of a button. But the opposite, as I wrote above and as Michael also noted, is not possible in the general case.

For simple cases it may be possible. For this reason, we have implemented an import functionality, which tries to bring in the Onshape model and convert it into Phi. In case it fails to convert the whole body, the next best thing is to convert some of the faces. Still, sometimes the faces that ARE converted may look different, as we try to recreate them based on our own maths. To make the above more predictable and help users prepare their Onshape designs before importing them to Phi, we provide an explanation of the issues that may inhibit its conversion, along with possible workarounds . You can find them in the import interface, under the toggle where you ask Phi to try and convert the model (see image below).

Since I mentioned the maths, Phi uses our own, much improved and extended version of n-sided surface patch mathematics. I’d also like to give a very superficial insight: what Phi does is it takes the loop of edges around any face, plus some other constraints (tangencies etc), and it tries to fit a surface onto these edges as smoothly as it can, a bit like stretching an elastic fibre over a wire net. So given a loop of edges, the result is, by its nature, not always the same as the face that you may be trying to import.

But there's some help on the way. If Phi fails to convert a model, it will bring it in as a reference (it will look transparent blue). This way, the original body will be displayed unchanged, and you can use it as a guide for your design work. You can attach your Phi vertices, edges or faces onto the reference, you can project faces onto it, and you can selectively convert some of the faces into Phi faces. Is this perfect? No, but it's the best we could do for now as we keep working on it.

There's a tutorial explaining all of this, and our next weekly webinar (they've been paused for the summer) is incidentally on exactly this topic of importing from Onshape, so a few days before it goes live I will add one more comment here for anyone interested to join.

There are some older comments above regarding curve and surface quality, I just want to assure you that we're working hard to constantly provide improvements. Already the edges are much more stable and robust (see for example below the curvature combs for a model similar to the decanter above), and we  aim to have more improvements coming in the future, including major ones. When this happens we'll let everyone know.

Again thank you for checking out Phi, we're always happy to interact with users, answer questions and discuss anything, including complaints.

Stephanos