I don`t want to copy Solidworks, Freecad etc… I only think it should be easy to follow which lines/curves are constrained with which option.
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Constraints… A bug sold as a feature!
“Our software is so powerful, it will move your geometry around if you aren’t careful. So we want you to constrain the bejeesus out of it, so we don’t have to bother with geometry stability in the UI.”
That’s what I hear whenever constraints come up. Crap software, sold as ‘powerful’. The same Jack tells me that his software only deals with ‘solids’ - as if anything digital can be at the same time solid.
Seriously! Constraints are not something I will ever use. The geometry ought to be constrained in the software, behind the scenes, never to enter the UI.
Have you every used a 3D modeler with constraints? Inventor, Solidworks, etc…?
It is quite a powerful tool when used correctly.
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on your side!
edit:
now I see that exactly this line was quoted already several times. may be a sign of how strongly some users feel about this.
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Of course I have used SW for several years, not that it matters to the discussion.
My experience is that in practice, that one hole that only has one constraint, invariably shifts slightly, not aligning with its hole pattern.
Constraints work well for those personality types that love process, procedure, overdefinition, and one single ‘true path’.
Your caveat “when used correctly” tells the whole story.
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I couldn’t agree more.
Then again, I am sure there are perfectly reasonable use cases where setting up correct constraints is worth the effort.
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Software without a Rhino-style command line feel non-linear and disconnected.
I wish Blender had a command line. Such an essential feature, it practically guides you through the options of each command.
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This applies to a lot of things, not just constraints.
E.g. knives are safe to use when used properly, if not used properly one could kill him/her/themselves in the worst case.
I’ve used Solidworks too and was always annoyed on how it insisted I should use constraints (i.e. kept “complaining” the object was not fully defined even when it was technically speaking not needed to add additional constraints than the minimum I used).
My experience is that most people who dislike constraints either didn’t use them properly (e.g. overconstrained things or used the wrong constraints for the task needed or used them incorrectly) or simply didn’t understand them well enough to use them properly and know when they should (not) be used.
Your example of the hole having only one constraint is a typical one of not properly using constraints. And also typical for blaming the tool and not the user.
Not to say that tools can’t be junk, but junk results can’t always be blamed on the tool either.
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Woah Art, Let’s not jump to conclusions here. The same hole-shifting problem happens to veteran SW enthusiasts, as well as those of us that use the software under protest.
I am here to tell You - that any cad software that moves geometry around just because I don’t specifically tell it not to is Junk! And not worth my time fooling with!
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@denbutler My point was that if there is only one constraint to that hole and it still moves then usually it means the constraints weren’t used properly, whether the wrong constraints, not enough or too many or whatever. Also I said “most people…” i.e. it doesn’t apply to everyone.
9 out of 10 times when there are issues with constraints it are using the wrong ones, too many or not enough or someone not (yet) understanding how to use (or not use) them properly. That being said, even I get it wrong with constraints occasionally if something doesn’t behave as expected with more complex setups and then have to adjust them.
If it was properly constrained and then still moves the way it shouldn’t, then something is defintely wrong somewhere that needs to be fixed.
That I agree with, if there is no logical cause for geometry to move around then it is a serious problem, maybe even junk as you state it.
Otoh there are bugs in every CAD program so I prefer to work with the programmers to sort them out. If they don’t care to work on those bugs then I’ll move elsewhere if possible.
Flamingo plugin is becoming obsolete. Rhino Nature plugin is better choice. It makes good trees, shrubs and grass. Its price is ~$180 to ~$250. Its website is here: http://rhinonature.com
Twinmotion, Enscape and Lumion programs also make good trees, shrubs, and grass, but are more expensive than Rhino Nature. (I described them in this thread.)
Vue is stand-alone plant and scenery generator. Its price is $199 to $750 per year. Its website is here: VUE: Overview
Xfrog is a plant generator. Stand-alone version costs $190. Plugin for C4D or Maya costs $250. Its website is here: http://xfrog.com/
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I prefer to look at constraints as ways to integrate design intent into the model. You have to be considered in how constraints are applied and how they affect the resulting geometry. Rhino currently lacks some of this ability to include design intent (excluding GH etc) so offering constraints as an option is a good development in my opinion.
Design Intent is integral to the model - to every model. You can’t make a model without intent, and it comes through loud and clear. I believe what you are seeking is the tree - the way to step back through the design to see the steps. Is that correct?
No, I’m not talking about the feature tree. More sketch constraints and variables.
Yes, you need intent to model something. I’m referring to building intent into the model, so that the model or parts of it behave a particular (intended) way when edited. Using constraints in SW/Creo etc is one way of doing that. There may be similar ways to control geometry in Rhino using the new constraints maybe also with history.
Ah, here is the miscommunication problem.
I assume that all sketches, construction planes, history, etc. will be purged from the finished product - a model, and only a model, all intent captured.
You assume a quick edit, or a snapshot into my workflow, so you can copy, or have it copied and edited overseas.
Nope, That information costs you extra!
Sure - in the finished product. I was talking about during the development process.
Yeah nah, I’m not that interested in your workflow but thanks for the offer.
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This is the key for me - “development”
We do a lot of plastic part design (housings for consumer products, medical devices etc.) and having a model properly constrained allows for fundamental changes (wall thickness, the location of some other component affecting geometry etc.) to propagate through the model without much work. The initial work of constraining the model allows for subsequent changes and iterations to occur with relative ease. It’s exactly the reason I don’t use Rhino as a primary design tool, because I rely heavily on geometric constraints to allow design flexibility and the ability to make changes that my model responds to without breaking.
(I don’t really understand the debate here. If constraints don’t suit your workflow, cool. But to assert they shouldn’t suit anyone’s workflow is absurd)
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Can you please use another post to discuss if constraints are good or bad for you?
If someone wants to seek for Good CAD programs this debate will not help.
I would also give my opining on Direct vs Constrains Modeling, but not here.
Feel free to delete my post too.
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We’d love to have your input on constraints here:
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