Direct Editing, SolidWorks, Instant3D and Move Face
There is a good discussion going on about Direct Editing technology between Paul Hamilton, Deelip, Ken Wong, Ralph Grabowski, and CEOs of Think3, Alibre, a founder of Spaceclaim, and a lot of other folks on a number of different blogs. I think now that Spaceclaim has been around for a while, and Synchronous Technology has had the opportunity to make the rounds, the discussion has a bit of a baseline this time. Some of the pedants are not involved this time, so I think it is a more rational conversation. It’s a good conversation, and it covers a lot of ground, so I don’t want to rehash it all for you. I think it was spurred by the nearly simultaneous press releases about Autodesk Fusion and SynchTech2.
There is still a bit of misinformation, though. Some people are using the words SolidWorks, Instant3D and Direct Editing all in the same sentence, and these people aren’t SolidWorks users.
It’s interesting to me the people who have NOT shown up for this discussion. SolidWorks allows its users to be their voice in web discussions. How interesting. The user group guy who claims the title “SolidWorks Evangelist” doesn’t seem to believe in the web. The SolidWorks people who believe in the web aren’t users. The users who believe in the web and participate in these discussions get excommunicated by corporate. I’m not sure if any word other than stupid really characterizes SolidWorks lack of participation in discussions of this sort, and the web in general. Look at the army of (paid) bloggers Autodesk has fielded. SW has web people on staff, but they are web community developers or web marketers, they don’t really have any web technical personalities. Go here to see how many web technical personalities Autodesk has.
I’ve talked with some SW people about direct editing topics, and the only way I can characterize their side of the issue was that they don’t feel any sense of urgency. Now maybe I was talking to the wrong guy (I wasn’t), but I don’t think SolidWorks is not going to go out and turn the software on its ear just because Solid Edge and NX did. I don’t think they will build a new product just because of Fusion (how many failed modelers is Autodesk responsible for?) I think SW will just enhance some of the tools they have, and it will be maybe 3 enhancements of the typical 150 that come every new release. 2010 beta is literally days away, so we will see shortly what the immediate future holds.
Anyway, back on topic. First of all, Instant3D is NOT direct editing. Instant3D is an interface gimmick, using parametric methods on a purely history based model. The fact that it looks like direct editing is entirely coincidental.
When you use Instant3D to change a part, you are NOT making direct edit type of edit, you are making a parametric, history based edit. Granted, you are skipping some of the less desireable aspects of history based edits like having to unbuild and rebuild the model, but I assure you, that is still happening behind the scenes. The fact that the interface looks like a direct modeling interface and that it has fooled even some bright people into saying this compares to Direct Editing is probably good news for the spin marketing group. They will get the credit for doing direct editing without doing the work.
Instant3D does not add features to the tree because it is just editing features that are there. It does require rebuilding the model, including features that come after the feature that is edited with Instant3D. This is the main difference between Instant3D and Direct Editing, especially in light of SynchTech’s claim to be 100x faster in certain types of changes (due to the lack of rebuilds). Where direct editing actually has an advantage, you shouldn’t take it away from them.
The Move Face feature in SW does create a feature in the tree. I’ve said a lot of times, along with some other respected users, that Move Face is a cheap and dirty tool. It is not on any best practice lists except when dealing with imported geometry. But sometimes it can get you out of a modeling bind. Having this tool available is a definite benefit to users. Move Face would be a direct editing tool if it did not create a history-based feature in the tree. So again, almost direct edit, but not quite. It has the direct edit advantage that it doesn’t matter how the face was created, you can just move it, but it doesn’t have the direct edit advantage that there is no tree to rebuild.
Interestingly, you can combine Move Face with Instant3D, but look at what happens. It starts measuring the Move Face feature at the end of the initial extrusion. It is just allowing you to drag the face offset distance. Again, it’s a bad idea to mix this with regular parametric modeling if you don’t have to because of stuff like this.
Part of the discussion was about is it “Direct Edit” or “Direct Modeling”, and someone made the argument that rather than giving us a new way (old way really) to edit stuff, why not just a new way to create stuff? Somewhere in there, I think someone got boolean modelers confused with direct editors. Well, I believe in the addage that says “create something once, edit it a dozen times”. And that’s really true, not just because of flaws in CAD tools that don’t allow us to create what we think, but because of flaws in our design and business processes that seem to always require something different, regardless of where we start from. I think tools for editing are great. That’s what I need most.
Anyway, if there is one use for Instant3D I like best, its the use with fillets.
You can grab the blue ball on a fillet and drag its size. That, if nothing else, is brilliant. I’ve always dreamed of a macro
that would maximize fillet size, and this is the thing that comes the closest.
Fillets are really one of the whole direct editing schemes biggest
downsides. There are some inherently history based things that fillets do, but I haven’t seen any of the direct editors handle these yet. The image above shows how the FilletXpert in SW can create fillet intersection/overlap options.
I have to admit I was impressed with how SynchTech handled shells, basically as a wall thickness. This has advantages and disadvantages over the history based method. The big advantage was that it enabled you to shell selectively, where doing that is a huge difficulty in history based systems. Still, I don’t think that it is a limitation of the technology, just a limitation of the current implementation in SolidWorks of the Shell feature. I’m confident SW could make Shell to shell selectively if they wanted to.
What does it all boil down to? I think there are some people who believe that these direct edit only products (Spaceclaim, Fusion, CoCreate, Solid Edge wST) are going to take over CAD. The rest of us seem to believe that the future will look more like the present, but with more direct editing options in our history based parametric modelers. The critics say that Alibre and SolidWorks are left out in the cold right now because they are the only ones now waving direct edit banners. According to some, SolidWorks is being hampered by Catia’s reluctance to share the direct editing tools in V6. That may or may not be true, I don’t have any idea. I thought Jeff Ray was brought on to make SolidWorks a lot closer to the DS parent. If they wanted to keep SW at arms length, they should have kept McEleney.
I would like to see changes to history modelers that are much smarter than the current generation, where it treats the geometry like dumb (direct edit) data until a change is made that requires a rebuild. I think that some smart folks put their noggins together, there is a solution that combines the best of history with the best of direct. SynchTech certainly isn’t it with its toggle approach (a part is either history or ST, not both). I think SolidThinking has some very interesting solutions which I wish some of the mainstream people would comment on, or dissect a little bit.
Matt-
Very informative post.
99% of my designs are machined parts, usually with a tolerance of +/- .005″. So when editing my parts, I mostly add or subject a known amount, like “make this shaft .025″ longer”. So, I just don’t use Instant 3D nor Move Face. I don’t trust the displayed ruler, I want to type in my dimensional edits.
Devon
That’s “add or subtract a known amount” coffee hasn’t kicked in yet.
Devon
Great post Matty! I talked with SpaceClaim’s founders at COFES and downloaded a trial and I must say that conceptual modeling is extremely fast. I think the approach is intuitive and model changes are snappy. I agree that I3D is not Direct Editing but do think it is a much easier way to change a history based model without having to feature hunt. SolidWorks does need to look at integrating this technology into the product soon, not because the competition is doing it but because it could be a huge enhancement for the user. I think back to V.2003 when we finally got multi-body support. Like you said, beta is around the corner so I hope that some of this is addressed. The more I use DE, the more I want it.
Matt,
Great, useful post as always. You point out a good detail with feature order and rounding. And we had anticipated this user concern. With ST2 (just announced – due out in Summer) you can right click any round and say “reorder rounds” and get the alternate answer. Of course since this is synchronous, there is no history tree in play here, so neither does it take an expensive regeneration, nor does it add an extra feature to the tree. I couldn’t put my hands on the demo video link easily, so I just made a quickie and posted it here:
http://screencast.com/t/wiCH6njry0S
Note that, as in the second example shown, there are various “overflow” cases for order of operation that need to be handled as well and are handled in ST2 as shown.
One of the more interesting aspects of your discussion is the notion that there need not just be history-free and history-based. There should be a blending of technologies, taking the best of both worlds and this of course is the idea of Synchronous Technology. I think we have a much better example of this “blending” in ST2 with the implementation of Sketch-based procedural features. You may recall that a procedural feature is a true editable feature, but without replay of unrelated features. Of course in ST, we only had “Hole” which frankly did not demonstrate the concept completely enough.
With sketch-based procedural features in ST2, you get the best of both worlds. You edit the SHAPE using a sketch, but you edit the LOCATION using 3D PMI. To me the best example for this is a bead in sheet metal. A bead is a complex formed feature that is defined by its centerline and some geometric parameters. It would be hell to try to edit it “directly” by interacting with the faces. It is MUCH easier to edit it via its original sketch. And that is the way it works in ST2 – features which “make sense” (dimple, bead, drawn cutout, helix, etc.) are edited using their original sketches, but the edit is computed locally, without any feature tree regeneration. And of course you can position them with the steering wheel or with 3D PMI dimensions that drive their location. I’m sure there will be more sheet metal demos, where this shines, hitting the streets soon.
Dan, that was a very interesting comment. The term “reorder fillet” kind of implies there is an underlying order or history hidden from the user. It is also interesting to see that ST is developing into a kind of hybrid direct editing/edit by sketch parametric modeller.
This is interesting because surely this is the precursor to editing surfaces via curves? Of course the difference there is that a major surface edit affects a lot of things and not just a localised feature like a bead.
Are we seeing CAD companies recognising that there is not one way, but in fact what is needed is a combination of ST type technology and history?
excellent man
“The rest of us seem to believe that the future will look more like the present, but with more direct editing options in our history based parametric modelers.”
It’s amazing how hype and even excitement about tech can overshadow the reality. I like the idea of 3D becoming easier, but DE isn’t always the answer. It’ll change, more options, but as we’ve seen with 2D users, it’s a long cycle to switch over from a way of doing things.
It’s going to be interesting to see the changes over the next few years with Win7 and the whole cloud stuff going on. Glad you brought all this up man.
btw, I couldn’t see the images in Google Reader. ??
Hi Matt,
you know that advertising (video demonstration) are traps for larks.
I’m a NX user and ex SolidWorks user for 8 years.
I currently use SolidWorks for my personal projects.
As you rightly wrote, there are 3 types of editing (dynamic editing, contextual with history and contextual without history).
The dynamics editing in SolidWorks is covered by the Instant3D that I find very interesting.
Direct editing with history, which is very low in SolidWorks, I find it very useful in imported projects and in those situations that lead to change an error in the reconstruction of the model or changes in the FEM.
Direct editing without history is a flop, is useless.
If I modify an imported model, there is no trace after a few days and I don’t remember the change that I did, same thing if he does one of my colleague, worse yet after six months.
SpaceClaim has the same philosophy of ST, or vice versa …. but I saw the video that if you mistakes to remove fillets for FEM analysis, after you hold it so, unless UNDO.
The Fusion will be a DM with history.
Only Siemens and SC have this abomination.
SE and NX users (designers) do not use the ST, a maximum of DM with history.
Deelip Menezes as you said he is not a designer.
“…It starts measuring the Move Face feature at the end of the initial extrusion….”, sorry Matt, but on my SW2009 SP3.0 doesn’t happen.
Instant3D start to the value set in the move face.
Can you verify ?
@dan_staples1
Dan, I agree with Kevin that you’re kind of conceding history based design when you use a word like “order”. I don’t know how you get past the idea of fillet order. The only thing I can see as a non-history based fillet intersection is the setback fillet that Ben Eadie shows at the end of this video: http://ia300241.us.archive.org/3/items/IcosahedronCont/IcosahedronSurfaces.m4v
I’m sure you guys have already done this, but I’m now kind of grappling with the question of what the relation of history-based features are to the brep model. In the end, brep is brep, but what’s the difference between what we have come to know as an “intelligent” model and what we have come to know as a “dumb” solid?
In the end, isn’t the brep always dumb? Parasolid data itself is static, isn’t it? Is the only criteria for “intelligence” a brep that is rebuilt at every change? Surely the software can use info about changes more intelligently than that.
Another direct edit problem is that when a face is consumed, you can’t get it back. I see this as maybe the the killer sticking point that you guys just can’t get past.
If you have sketch based procedural features, fillet reordering and the ability to get back consumed faces, then I’m not sure what is left, aside from the ability to explicitly reorder features.
If the history based people are able to figure out how to make rebuilds more selective, then I think they have negated your benefits without succumbing to your shortcomings. In the end, what is the difference between selective rebuild and direct edit? They both have to change the brep. Selective rebuild does keep track of all faces created by all features along the way, so they can recover consumed faces,,,
Why doesn’t SolidWorks field someone like you? I really like the fact that you pipe in to these conversations!
ps – any chance I can get my hands on some of that ST2 pre-release?
I suspect the industry has not yet converged on direct modeling terminology. At SpaceClaim, we consider “direct modeling” to be a way of interacting with the model regardless of the underlying technology. If there’s a handle you can pull on to reshape a solid, it’s direct modeling. Direct modeling comes in different forms, such as constraint-based (ST), feature-based (Instant3D), and pure (SpaceClaim, CoCreate, KeyCreator), but they all deliver different benefits depending on customers design process and expertise.
-Blake (a founder of SpaceClaim)
cubalibre00,
It’s true that SpaceClaim has a undo and redo capability similar to Word, AutoCAD, and other desktop applications. That solves part of the problem, but we also have the ability to handle the changes over a long period of time and communicating those changes intelligently.
There’s a button in SpaceClaim called Save As New Version, that saves a document with an incremented version so your old copy doesn’t get overwritten. For example, design.scdoc becomes design.2.scdoc. When you realize later that you’ve messed something up, you can open up the old version copy the geometry you want, and paste it into the new design. Just like you would in Word. Usually, there’s a little slice and dice involved to merge the geometry into a solid, but that is a straightforward SpaceClaim activity.
If you want to see the changes you’ve made, SpaceClaim has a 3D markup feature that shows you changed faces and can show how dimensional values changed.
The benefit of this approach is that you can model however you want whenever you want, without ever having to second guess yourself. If you just make a little mistake, undo. Realized you made a mistake a week ago? Copy from an old version. It’s pretty freeing, especially in the concept phase and when repurposing designs for CAM and CAE.
Especially cool: you can copy and paste throughout undo history. For example, let’s say you added some material that ended up filling in a hole. You can copy what you made, undo back, paste it in, and merge everything together so the hole still exists. Alternatively, you can undo back, copy the hole, redo forward, and paste in the hole. It’s fun and powerful.
-Blake (a founder of SpaceClaim)
@bcourter
In all honesty, that sounds powerful, but its also at least as complicated as keeping track of history. Undo, redo is just a history you can’t see, right? And then copying from an old version is more history you can’t see. Anyway, plenty of other software can copy and paste from old versions, but its a clunky solution.
I’m wanting to see a big improvement in some of this, but it’s just a new way of saying the same old stuff.
@matt
On the question of using the term “reorder rounds” — I’ll be honest, I am not totally a fan of it. I kind of prefer “give me the other answer”. Even though we’ve gotten used to using reorder to achieve this, to a designer/engineer, he either wants the triangle patch or the torus answer. The fact that he has to reorder to get one or the other is a manufacturing, not a design concept. So yes, the use of the term “reorder” is a bit of nod to existing (history-based) way of thinking.
On the “dumb brep” thing I truly think its a misnomer when you think about the way synchronous technology works. To me, the brep is incredibly smart. It has all sorts of knowledge embedded in it — stuff is tangent, concentric, parallel, symmetric, horizontal/vertical and more. And its not that there are stored constraints representing this — it simply “IS” that way. All that information is IN the brep model. It just takes synchronous technolgy and Live Rules to mine it of the brep in an intelligent and expedient way and then enforce the intelligence on edit.
@kevinquigley
Kevin,
As I mentioned to Matt, “reorder” is just term for user comfort. There is no actual order for features in synchronous. They are all peers in a collection, not a linear dependency tree.
On your point about “maybe there should be a merger of ST and history” I think some clarifiction is due. A lot of people (incorrectly) believe that Synchronous is just a history-free system — that we went from being history-based to being history-free. This is not accurate. In fact, we think there are good things about history based and good things about history free and that synchronous is a merger of these worlds. I wrote a piece on this a few months back that might explain where we are coming from. See here:
http://siemens.pmhclients.com/index.php/the-three-pronged-fork-in-the-road/
Dan, as you wrote :But why should you, as the user, have to choose”.
I respond to you that I must choose.
In SE, or I work in ST or I work in the classic mode. I can’t go from ST to classic, but from classic to ST, yes.
On NX I can do it, but I lose everything (holes and fillets are kept for your comfort) I created in the classic mode.
Designer can’t choose the approach, but is the CAD that choose for us.
As I said to Blake (a founder of SpaceClaim), we designer need to track our changes, because our project evolve and because if we work on a multi-user environment it’s very difficult understand what happen to the project.
I’m NX6 user and I use DM with history mode, never ST.
I tested ST, day by day, I can not find the utility…
On imported file I use DM and on complex file I use DM at the end of the history feature and the recalculated process is very very fast.
You have done a lot of publicity, but nobody SE / NX users use ST technology….ST is a flop as CoCreate CAD and SpaceClaim.
@cubalibre00
I don’t mean to sound rude, but it sounds to me like you need to get a PDM system. Revisions, changes, history… all of that is tracked and documented. So, you can use the ST technology to make the quick and fast changes, and have copies of each and every revision that was made. If you need to make a change based off a much older version, you can simply call up that revision, make the change, and save it as the new, latest revision.
If you simply can’t afford or use a PDM system, then yes, history-based modeling with a feature tree is a perfect way to keep history and track changes.
@Bruce Buck
Hi Bruce, I’m NX6 user and we use TeamCenter as PDM.
I don’t know what do you do, if you are a designer or a consultant and how much is big the company where you work, but when I speak about keep track of a project is because if you don’t know, usually a project evolve every day for many months.
When I project I modify my file, I add, I delete, I change, etc..the same my co-workers on the same project or different project.
ST technology don’t help me….you have to try….
Hi Matt, when you say “In the end, what is the difference between selective rebuild and direct edit?” my answer is : the feature
description, that is a hole is a hole and not a face move. Also you can have relations between features and these can be either solved simultaneously (the ST approach) or sequentially.
Also a comment on Dan’s words : “To me, the brep is incredibly smart. It has all sorts of knowledge embedded in it — stuff is tangent, concentric, parallel, symmetric, horizontal/vertical and more”. My question is: what are the constraints that are due to be kept and what are not ? You cannot seriously dig an entire Brep and decide which parallelism is good and which is not. The answer os ST, as far as I have
understood, is semi-automatism. I wonder if it is not more clear to let
the user tell it. It does not seems to me so smart a Brep…
Roberto Ciarloni
CTO think3
@matt
It’s no more complicated that keeping backup copies of a Word document around when you make major changes. With modelers like SpaceClaim, you just have a lump of solid, just like with word processors, you just have a lump of text. I suspect most engineers understand the concept of undo and redo and wouldn’t be too confused about copying some good stuff, undoing back to before it existed, and pasting it back.
Of course, for detailed design, it’s important to document design intent with feature and constraints. In the early phases, however, when you’re aggressively exploring design possibilities, direct modeling can be extremely liberating.
@cubalibre00
I think there are some misunderstandings about “keeping track of changes” and “history”.
History keeps track of design intent when you create geometry and features. I.e.: creation of a sweep and its parameters, hole and its parameters, and so on.
History does not remember following changes to the parameters, does not remember feature reordering or deleting. Just keeps the last version.
If you want to keep tracks of such changes, you need to save the copies of your model at the several steps of its evolution, using a PDM or not.
So, I don’t see how using NX you can have the trace of the changes you or your colleuges made to the model, apart from adding features.
Alberto (a developer of the history engine in think3)
@albertosavelli
Alberto, you speak well English, but I use Google Translate and often it’s hard to me transfer my Italian thought in English.
In this discussion we talk about, direct editing.
Direct editing is used usually on imported parts, in very complex modelled parts or in FEM situation.
In those cases I use history mode to keep track of the design intent and the changing.