Re: Import 3d Iges data

objects that modeled using polyface meshes (what

>many nowdays call wireframe

??

Reply to
Cliff
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Sorry for the delayed response, I've been out of town. I have no idea where my "version 5" reference came from... typo? It was on version 2003 that we attempted to import a simple 1" square cube which was created as polyface mesh object in AutoCAD. To describe the object a bit more, if you explode the object in AutoCAD, it is made of

3D faces.

If I recall correctly, the only option for me at the time was to export the mesh object from AutoCAD as a IGES file, then import that to SW. However, the results were not a cube, but rather 6 separate surfaces in SW. It seemed that in the translation the surfaces of the cube would not end up as perfectly parallel because of rounding errors.

I just researched some of the old messages on the subject. Polytrans is one option, and we have an older version... perhaps the new version is better at it now. One vendor posted back in 2003, saying, "Capvidia is developing a new add-in for SolidWorks to create parametric models from STL/Mesh or point clouds. We hope to release it this fall." Perhaps FeatureWorks is the current equivalent to this software. But I am not in need of parametrics... just a dumb object.

Other people posting at that time were also having difficulty getting usable meshes to translate into Solidworks. It seems the process has always been there, but may not work as smoothly as we would like. I guess all that is left to do is to try it on the new version and hope the process has improved.

Joe Dunfee

Reply to
Smiley

Joe, Just don't use meshes or STL-like files .... It's a really dumb idea. Think of the entity count & database just to begin with. STL files & meshes are created for certain specific purposes for certain applications from parent surfaces. The parent surfaces & geometry are always better representations of themselves .

Reply to
Cliff

Joe,

That's because polymesh objects are very imprecise "approximations". Solidworks, and all the others, are "exact" modelers.

I'm very skeptical about the usefulness of data produced in such a way. Like I said in my previous post, "there is no underlying mathematical data describing the shape". Any system capable of doing that would require allot of intervention from the user. The relative accuracy of the objects would be very poor at best. Of course, if you only need objects for display, this shouldn't matter.

Nope, Featureworks is designed to work with real surface data (mostly analytic).

Not in 2004, non planar features still display as faceted, even when imported as a graphics object.

There seems to be alot of folks that would like to use polymesh objects for things like rendered scenes and such. I can't blame them, there's an awfull lot of available models out there. There really is no reason why Solidworks "can't" allow you to import a mesh as a graphics object/objects, and apply "smoothing" functions to it. This is what polymesh modelers do. The mesh isn't really smooth, it's all done with the shading functions. Ironcad has been able to do this at least from version 2.

However, attempting to use polymesh files as a basis for a manufactured design is not only a waste of time, it's just plain dumb.

Regards

Mark

Reply to
MM

It all depends on what you are depicting and your usage. In my case, I've have instances where I want a representation of a theatrical spotlight to get a feel for how much space it has to move around and just to show that the object is there. I've also inserted meshes of things like people, air conditioning condensers, and forklifts into AutoCAD drawings for similar reasons.

A mesh is also capable of precisely representing a faceted object. The square tubing (and things like U-Channel) I mentioned at an earlier post can be well represented, even if the 1/32" radius on the corner is not depicted. This is a case where AutoCAD's difficulty in editing ACIS solids tends to force users to use meshes for weldments using these kinds of structural steel. Such drawings seem to be forever quarantined from the solid modelers which can't import them.

Sorry to be argumentative (I do value your replies), but for me, importing mesh objects is something I would have a lot of use for.

Joe Dunfee

Reply to
Smiley

I agree, "display objects" being the keyword here.

"Precise faceted object" is an oxymoron. Solidworks uses double precision 64 bit math, and very advanced mathematics to calculate surfaces and boundaries. That's precise.

Like I said, Ironcad has been able to import and display smooth mesh objects forever. Solidworks "could" do it if they wanted to. Being able edit them would be a bit of a stretch.

No problem,, but I think your kinda stuck in the "Autocad does it like this" mode. SW doesn't do "anything" like Autocad, and never will. 3D models are not "drawings".

You'll need to lose the Autocad mindset if you ever want to be productive (and happy) using modern tools.

Regards

Mark

Reply to
MM

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