Talk:Solid modeling

Merge
Those short articles: all try to explain some (I guess very basic?) capabilities of solid modeling (or even narrower, of CAD); they fail to achieve this, as far as I am concerned, so maybe it would help to include them in the proper context here, per WP:NOT#DICT. Some very simple, very concrete ("brick") examples would help to make them comprehensible for a layman. --Kubanczyk 21:58, 25 October 2007 (UTC)
 * Parametric feature based modeler
 * Change state
 * Transmigration operation
 * Euler boolean operation

Parametric feature based modeler is already included in some sense in the solid modeling article. Euler boolean operation is related only to the boundary representation and can be merged to that article. --Onna 09:20, 11 November 2007 (UTC)Onna

I have no idea what the Euler boolean operation article is talking about. Generally, boolean operations are useful because they provide an intuitive way to make holes in an object, ie, change its genus_(mathematics). Regular boolean operations don't result in MC Escher like objects, unless they're implemented wrong. The article should be taken down or rewritten so at least someone familiar with the concepts they're talking about can understand it. Jan 10 2008 Gilbert

I don’t believe Change state should be merged at all, it’s not just a Solid modelling concept, any computer based action is based on state. TBH, that article needs more work on it’s own or deletion -- johndrinkwater (talk) 19:54, 20 March 2008 (UTC)

I agree that parametric feature-based solid modelers are a special case of solid modeling, as are boundary representation and constructive solid geometry techniques. They should all be merged into one article. Transmigration, change state, and Euler Boolean operations have meanings outside the contest of solid modeling and should remain their own subjects.--Cyon Steve (talk) 19:08, 26 June 2009 (UTC)

The animated gifs on this page are horribly distracting. 24.39.42.3 (talk) —Preceding undated comment added 02:11, 11 April 2010 (UTC).

Overly bold edits
Schwarrx. Your wholesale replacement of the entire article with content of your liking (via this series of 67 back-to-back edits), is a bit too WP:BOLD and does not seem to be at all in keeping with the collaborative-writing spirit of Wikipedia. Your contributions have been instead added as a new section to this article. I suggest you take your time to discuss things further with other editors, who also labored greatly to contribute content to this article and shouldn’t see their efforts entirely expunged from existence. Greg L (talk) 22:32, 24 April 2010 (UTC)

Greg L. I had saved the existing material and was going to try and incorporate it at appropriate spots, but I had many issues with the way the material was presented in the first place. Solid modeling is not CAD but is concerned with providing mathematical foundations for CAD, which was completely missed previously. Before I made any edits there was a lot of hand-waving going on about specific terminology. For example, there is no such thing as Euler boundary representation, sweeps are not the same thing as sketch based modeling, voxelization is not the same as regular sampling that is needed for accurate integration and FEA, and the history of solid modeling provided is treated as the history of CAD which is a separate topic, etc. All of this is not a matter of opinion, but is based off several well cited research papers which I have included in the references. Moreover, the earlier edits seemed to reference just "LaCourse, Donald (1995)" which is not even a standard reference and in fact has poor reviews on Amazon.com. I was attempting to make the exposition precise, unbiased, and consistent with solid modeling research, as I think the article should be written this way and was not done so earlier. Also, earlier comments on this page ask that animated gifs be removed (they are very distracting) and also ask for accurate descriptions (esp Euler boundary representation, which you have added again). I understand that a lot of work may have been put into creating this page, but I think it is important to be consistent with what is going on in a mature research discipline. Schwarrx


 * Try to remember that Wikipedia is directed to a general-interest readership. You clearly have a Ph.D.-level grasp of this material. However, material such as Any X ⊂ ℝ3 can be turned into a closed regular set… and According to the continuum point set model of solidity, all the points of any X ⊂ ℝ3 can be classified according to their neighborhoods with respect to X as interior, exterior, or boundary points. Assuming ℝ3 is endowed with the typical  Euclidean metric, a neighborhood of a point p ∈X takes the form of an  open ball… is far beyond the aptitude of most visitors to this article and will be grasped by only a subset of our readership. It strikes me that other editors have added material they find to be germane and topical to this subject. Though you might feel otherwise, and would like to have a heavy emphasis on solid modeling’s mathematical underpinnings, it is clear that many Wikipedians here see a wider treatment of the subject. Accordingly, I suggest you direct more of your efforts on correcting errors in the non-mathematical portions of the article rather than delete the non-mathematical portions. A side note: it is far too easy to simply regurgitate arcane technical and mathematical verbiage onto Wikipedia’s pages; the trickier part is starting off a mathematical treatment with an encapsulated explanation geared to a general-interest readership at 12th-grade difficulty level. The best of our writers seem to be able to pull this off. I wonder what you can do in this regard. If you are an educator, then your university’s servers may be a more suitable venue for this type of material to be presented to your students. If you are a college grad with a mathematics degree, you have your work cut out for you in making your contributions more accessible. I suggest you start out your efforts here by re-ordering the organization so the arcane mathematical underpinnings goes last in the article, which is the classic method of all technical writing whereby one starts out using simple-talk and have the article grow increasingly complex the further one reads. Greg L (talk) 17:48, 25 April 2010 (UTC)  P.S. I started out the re-ordering of the content (from easy to complex) with a basic edit. I trust you can improve on it from hereon. If you actually manage to add a plain-speak lead-in to your math section that is geared to the 12th-grade, non-math major and you find it does a good job explaining whatever in the world that section says, drop me a note on my talk page; I’d like to see what it means. Greg L (talk) 17:56, 25 April 2010 (UTC)

Greg L. You did not give me a chance to finish what I had to say in the first place (about other topics in solid modeling) and are criticizing the section titled 'Theoretical foundations' for being too mathematical, which is rather silly. If you are unable to parse the text, you should go over the links and try to understand what they mean because what you call regurgitating arcane verbiage is actually well established language, as postulated by the people who invented solid modeling. I would rather spend time understanding correct and established material as opposed to someone's incorrect and dubious view of the field in the name of a simpler presentation. I am sorry, but clearly you do not read mathematical pages on wikipedia which are written in precise language, and not for people who have a 12th grade grasp of the subject. An interested reader is expected to follow up on links and educate themselves, otherwise the quality of articles will suffer, as it has for this page. If you strongly believe in your technical views, we can have a debate and maybe even reach consensus but if you are going to resort to ad-hominem attacks and insist on a deliberately pedestrian and miselading presentation, then you should not be responsible for any edits on this page. I will however agree that presenting applications ahead of theoretical foundations makes text more accessible to a wider audience, but that requires careful writing and not just a list of techniques written in an incomplete and incorrect manner. So before you criticize my exposition, please take an objective look at what you are advocating. And yes, I have published a few research papers in solid modeling.

With respect to your question about testing neighborhoods of points - the idea of neighborhood testing against a set is to draw an infinitesimal ball around every point in space and see if the points in the ball consist solely of points inside the set (implying interior points), solely of points outside the set (implying exterior points), or points from both the interior and exterior of the set (implying a boundary point). This way, every point in space can be classified as belonging to a solid or not, and gives a precise way of guaranteeing solidity of a set.


 * I waited 15 hours after you posted to reply. On Wikipedia, that is more than enough. Accordingly, I can’t possibly help it you think I “did not give” you “a chance to finish” what you had to say. Moreover, I used no “ad-hominem attacks” against you. I simply wrote that the material is far beyond most reader’s comprehension and readers can’t possibly be expected to become conversant in advanced math concepts by clicking on links. I further wrote that you may feel that Solid modeling is not CAD but is concerned with providing mathematical foundations for CAD, but clearly, many editors feel that the subject of solid modeling is properly broader than that. Wikipedia is ruled by consensus. I can’t see that you are abiding by consensus when you replace an entire article with your own content dealing strictly with the arcane mathematical underpinnings of the subject. Your contribution belongs in this article precisely as that : a “contribution”. I suggest you exert greater effort in abiding by the rules of Wikipedia and its collaborative-writing environment. And finally, (with regard to “ad hominem attacks”): Quoting you: if you are going to .... insist on a deliberately pedestrian and miselading presentation, then you should not be responsible for any edits on this page. You should know that on Wikipedia, you won’t get anywhere with that sort of attitude and may well be blocked. Please respect the fact that this article has existed since 2004; other editors have other ideas too. I just reverted some I.P. editor, who, apparently not impressed by your arguments (or finding your contributions unsuitable) deleted the whole bit you added. And, as I sense might be starting to dawn on you, other editors have ideas for the scope of its content that vary from yours. If you find some factual errors, please feel free to correct them. If you see assertions that need support, please cite them. But please don’t presume to come here and delete what has been stable for years and pronounce what you believe to be the proper scope of Solid modeling and how it is no more than a treatise on the mathematical underpinnings. Greg L (talk) 20:09, 25 April 2010 (UTC)

Greg L If I have to correct factual errors, I have to rewrite pretty much the entire page, which takes some time. The page may have been stable since 2004 because no one has taken the time to correct/rewrite what has been presented. In fact there is a comment earlier on this page that The article should be taken down or rewritten so at least someone familiar with the concepts they're talking about can understand it. Jan 10 2008 Gilbert I understand that this is a collaborative effort but you are assuming authority over the field and over what should be said about it yourself. I do not see anyone else arguing strongly and so I doubt the meaning of the word 'consensus' as you use it. You can say that you were simply trying to explain to me that my exposition was too dense but saying things like 'it is far too easy to simply regurgitate arcane technical and mathematical verbiage' is unnecessary and irrelevant because although you may not value precision and accuracy, other readers of Wikipedia do. Moreover, I added an overview section that should clearly indicate what I think is the scope of solid modeling techniques and it has been written in a general and accessible way. Schwarrx


 * The nature of your writings on this talk page appear to be the product of an experienced Wikipedian who’s been around the block a few times. Interestingly, your edit history suggests the contrary. This, combined with what is a brand new use for a previously unused account and the fact that you didn’t bother to create a user page suggests that you may have edited under different identities before. Am I incorrect in drawing this conclusion? If not, would you care to disclose what those other identities might have been? As for how you are doing now on this article, I have no problems. Greg L (talk) 21:27, 25 April 2010 (UTC)

Greg L If you must know, this is the first page I am editing. Up to this point, I have not felt such a strong need to edit any particular page. I am working on remaining sections. Let me know if there are other controversies.


 * I doubt there will be any further controversies if you continue in the same general vein. I think the article is in the capable hands of a knowledgeable and good shepherd. At least one editor, (∆ here), feels the article—in its present incarnation—is an “interesting topic.” Greg L (talk) 22:22, 25 April 2010 (UTC)

Hopefully no one got frustrated away from editing wikipedia ever again, you both appear to be knowledgeable experts and it would be a great loss for the community if any of you two not continue to improve this already great article. I, for one, believe that wikipedia should not limit itself to vulgarisation, all knowledge, however complicated and intimidating it is, has a place on this encyclopedia, the tricky part is to find where it belongs and how to present it. To that extent, I suggest that the mathematics outlined in this article be moved to their own page or reformated in a point form. Not being versed in this field, I will defer to an expert for this task. I did not read the entirety of your discussion, so I am sorry if this was suggested already.Tinss (talk) 18:08, 4 June 2010 (UTC)

Cleanup and conslidation
I did some cleanup and consolidation on the "Computer-aided design" section. I deleted the "entertainment" subsection altogether because it did not have any obvious relevance to solid modeling and cited no sources. I tagged other sections and subsections that are in need of sources. Most of the statements in the "Computer-aided design" section are vague and unverifiable, but I'm leaving them in for now to see if anyone comes up with references. If not, much of the text in this section should be deleted.

This article could use some clarification of "parametric" modeling, since it is mentioned in several places in the article. I don't know enough to do this. Oanjao (talk) 21:09, 20 January 2012 (UTC)

File:Jack-in-cube solid model, light background.gif to appear as POTD soon
Hello! This is a note to let the editors of this article know that File:Jack-in-cube solid model, light background.gif will be appearing as picture of the day on June 9, 2012. You can view and edit the POTD blurb at Template:POTD/2012-06-09. If this article needs any attention or maintenance, it would be preferable if that could be done before its appearance on the Main Page so Wikipedia doesn't look bad. :) Thanks! — howcheng  {chat} 21:28, 8 June 2012 (UTC)

Empty circles in the illustration
In the figure "Regularization of a 2-d set by taking the closure of its interior" there are several empty circles. There is no explanation but I assume these indicate exclusions, i.e. points which are NOT member of the set although their neighbourhood is (I am not an expert so this might be a wrong understanding). However, a closure of the interior should not contain any such points, because with them excluded it's not a closed set any more - its complement is the "open outer world" plus the previously excluded points, which is not open. Am I right? Lebeda Karel (talk) 10:24, 26 May 2015 (UTC)