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Snosrap
12-04-2007, 10:04 PM
With the likes of Inventor, Solidworks and other solids based 3D CAD packages, what are the advantages or disadvantages of using these tools over polygonal modelers such as LW, 3D StudioMax, Maya etc.? Currently we are using LW to conceptualize and render furniture designs and our engineers are using Inventor to engineer approved designs for manufacture. Couldn't our design department just use Inventor/Solidworks to conceptualize? I'd love to hear anyone's comments regarding this.

Thanks
Snosrap

jin choung
12-05-2007, 12:00 AM
solids are about self enclosed volumes... so it makes sense to use such modeling paradigms if you need to go out to stl or cam or something where "solidity" is a factor.

also, all tools to manipulate solids are designed to maintain such "solidity" and the integrity of the solid. there also is probably an emphasis of precision of measurements and such.

so along with some beveling and chamfering tools, most modeling operations are variations of booleaning one shape from another. right? you're pretty much limited to that.

can impose limitations on the ease of creating lots of different kinds of forms.
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but because of the requirement to maintain "solidity' you lose the flexibility that comes from being able to manipulate arbitrary surfaces without any strictures of "enclosed, convex shapes".

so you can do free form shapes a lot more easily and if being a "water tight solid" matters for manufacturing processes, this becomes factored in at the end where attention is paid by the modeler to make sure it is.

so instead of being limited to basically boolean operations, you have all kinds of mesh manipulation open to you.

basically, you have more tools, more options and it is EASIER and FASTER to pull off many kinds of complicated forms.
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not that you couldn't do pretty much anything in solids. and for certain objects, you MIGHT want to do it in solids.

it may for example streamline your production pipeline.

but like polys is to nurbs, sometimes ease of use trumps precision - especially when extreme precision is not necessary as in most entertainment purposes.

jin

Sande
12-05-2007, 02:41 AM
Like Jin said, precision is one factor to consider. Because shapes done with solids are based on mathematical formulas your objects maintain their shape and curves no matter how close you need to go - for example a ball is a perfect ball and you don't see any jagged polygons no matter how close you zoom.

gerry_g
12-05-2007, 12:57 PM
You do a sweep along a spline in LW what happens, it twists off axis the further it goes, so you double sweep it but there's no proper spline offset tool so your screwed in some instances, and what you end up with what you end up with. Do a sweep in a cad orientated prog, even a single sweep and it will maintain fidelity to the spline, and when you are done you will be able to toggle between various options as to how it swept the path, and when you drop the tool it's construction history will still be live, both the spline and the profile will remain editable, even after saving and up until such time as you decide to kill its history........ and this is before we start talking abut snapping, LW's weak point.

THREEL
12-06-2007, 11:24 AM
With the likes of Inventor, Solidworks and other solids based 3D CAD packages, what are the advantages or disadvantages of using these tools over polygonal modelers such as LW, 3D StudioMax, Maya etc.? Currently we are using LW to conceptualize and render furniture designs and our engineers are using Inventor to engineer approved designs for manufacture. Couldn't our design department just use Inventor/Solidworks to conceptualize? I'd love to hear anyone's comments regarding this.

Thanks
Snosrap

Don't talk yourself out of a job, Tim. :) If your company changes to one of those solid based programs, they might decide your job is no longer necessary. :eek: You know how they like to "streamline" their work force.

BTW--I'm pretty sure NSCC uses packages like AutoCAD & Solidworks for CAD work, and 3D StudioMAX for their computer animation coursework. I remember talking to them about :lwicon:. They said that they decided to go with 3DSM, because it coinsided with AutoCAD. They, also, discussed it with several outside sources.

I remember when I went there, Northwest Tech at the time 8/, they said that they would probably never need 3-D. Wow, I wonder what ever became of that mindset, and boy, how times have changed.

Well, anyway, that's my 2 cents worth.

Happy Biking!

AL

nub
12-14-2007, 09:22 PM
Well Timmer, you know my opinion on the subject :) .
I've thought for years that the engineers should have gone to Solidworks instead of Inventor especially because of the ties with SmarTeam. The argument against it was the amount of training time that had already been invested in AutoCad/Inventor. Never mind that the per seat cost of Solidworks was considerably lower than Inventor and they offered to come in and do some introductory training for free.

The hard part is attempting to integrate LW into the CAD workflow of the engineers.

NSCC does use 3DS MAX for the modeling/animation course, but I have it on pretty good authority that the instructor makes his best effort to keep the class as generic as possible by attempting to focus on concept and technique rather than what button to push. On the CAD side, they use AutoCad and Solidworks.

Snosrap
12-14-2007, 09:51 PM
Hey Nubby, hows the new job going? Great to see you jump in on this. We had 3 demos of Solidworks and they basically blew it as far as design goes with their BS and crappy rendering. Mr. Trosh is still somewhat considering it, but he didn't get a very enthusiastic response from his people.

Hope to see around these parts more. I'm usually hanging around here somewhere.

Cheers
Snosrap

nub
12-17-2007, 07:23 AM
The job's going pretty well, I think. It's a different world, though. I'm a in a bit over my head, but have been able to figure stuff out so far. I'm hoping to introduce some of the video/modeling/animation/product vis stuff to the engineers and marketing groups sometime next year.

I'm suprised that the SolidWorks demos didn't go over well. It must be a different group that came in than what I had talked to what...like 4 years ago. Wow, time flies.

Anyhow, if you want to get a decent, unbiased, hands on viewpoint, call SMC. They have a license and have been using it for some of their design work.

I don't think that SolidWorks would take the place of LightWave. You guys have gotten too good at quick product visualization for customers. But, I can see it saving the company some cold hard cash from a licensing standpoint. Rember that change is good. Otherwise you would have all been running 3DS MAX :bowdown: . HA!

Hang in there and take care!