i am glad to see some real active players on this list.. i wonder has anyone tried to use Bricad to subdivide a large parcel of land into lots and create the landscape for zoning presentations.
-------------------------------------------- On Mon, 12/26/16, brlcad-users-requ...@lists.sourceforge.net <brlcad-users-requ...@lists.sourceforge.net> wrote: Subject: brlcad-users Digest, Vol 56, Issue 1 To: brlcad-users@lists.sourceforge.net Date: Monday, December 26, 2016, 6:57 PM Send brlcad-users mailing list submissions to brlcad-users@lists.sourceforge.net To subscribe or unsubscribe via the World Wide Web, visit https://lists.sourceforge.net/lists/listinfo/brlcad-users or, via email, send a message with subject or body 'help' to brlcad-users-requ...@lists.sourceforge.net You can reach the person managing the list at brlcad-users-ow...@lists.sourceforge.net When replying, please edit your Subject line so it is more specific than "Re: Contents of brlcad-users digest..." Today's Topics: 1. Re: Hello and Mged command-line vs GUI. (Alexander Wallace) 2. MGED TCL acting differently command-line vs GUI (Nathan McCorkle) 3. Re: Computational Stability -- subatomic through the galactic and get "all the details, all the time." (Nathan McCorkle) 4. Re: Computational Stability -- subatomic through the galactic and get "all the details, all the time." (Nathan McCorkle) ---------------------------------------------------------------------- Message: 1 Date: Tue, 1 Nov 2016 09:32:56 -0600 From: Alexander Wallace <alexander.o.wall...@gmail.com> Subject: Re: [brlcad-users] Hello and Mged command-line vs GUI. To: BRL-CAD Users Mailing List <brlcad-users@lists.sourceforge.net> Message-ID: <9eb49d41-5de4-4cad-a942-226010f74...@gmail.com> Content-Type: text/plain; charset="utf-8" Interesting, thanks for that info. Running on linux and being free is important to me. Sketchup looks nice though. Thanks! > On Nov 1, 2016, at 8:30 AM, Bob Anderson <bob.ander...@survice.com> wrote: > > If you are doing machining, it is quite cumbersome to add fillets and chamfers to BRL-CAD regions. In our models we ignore them and in some cases remove them to reduce complexity. Sketchup does these quite well. There are a lot of add-ons for Sketchup that people have generated using Ruby code for woodworking and machining that would make this very easy to do. There is also a Sketchup dtabase of existing models that you can download. I mentioned that I used Sketchup to model my house, but I downloaded sink basins and toilets so I would not have to reinvent the wheel. > > I don?t want to discourage you from using BRL-CAD, because it has some really nice features, but its usability really does depend on your intended use. > > Robert Anderson > ? <> > From: Alexander Wallace [mailto:alexander.o.wall...@gmail.com] > Sent: Tuesday, November 1, 2016 9:50 AM > To: BRL-CAD Users Mailing List <brlcad-users@lists.sourceforge.net> > Subject: Re: [brlcad-users] Hello and Mged command-line vs GUI. > > Hello Robert, > > First thanks a lot for answering, makes me feel good to see active users of a product I pick up for learning :) > > What you write makes sense. > > It took me a while to find out that there was a ?sed? command, almost by chance, but then googling for it made me find https://brlcad.org/wiki/Changing_the_properties_of_primitive_objects <https://brlcad.org/wiki/Changing_the_properties_of_primitive_objects>, and so on. I was able to use it yesterday to select a solid and scale it and move it. This was good. > > The approach you point out sounds interesting as well! I shall play with it. > > Thanks for sharing the ability to script things using the source command. I had seen an example of someone piping commands to populate a database but I didn?t know about the ?source?? Information seems good on some subjects and hard to find in others. Some of the ?help? texts on commands are very cryptic and isolated (commands sometimes need to be used in combination but the help does not tell you that, such as ?sed -> sca -> accept?), but it is what it is and I?m sure it will get easier for me with time. Luckily there is a list like this and people like you to help us newbies! > > Is there a reverse of source where the steps to produce a database be output to a file? > > On your question: I?m not a profesional designer, but a hobby fabricator/inventor and from time to time it makes sense to put some ideas in CAD before doing it on the metal. I have never picked up a tool deeply, have only superficially used a few, and I would love to pick up one that I can develop better skills for? > > I love how PovRay scene building works, but it can?t easily be used for CAD as far as I?ve seen and don?t seem to have some advanced tools for design checking like materials and geometry checking that (i?ve no idea how to use) BRL-CAD has.. > > Anyways, thanks a lot for your answer, it was illuminating! > > I?m sure I?ll come back with more questions once I start building some parts I need to make? > > Take care! > > > On Nov 1, 2016, at 7:11 AM, Bob Anderson <bob.ander...@survice.com <mailto:bob.ander...@survice.com>> wrote: > > Hello Alexander, > > I?ve been using BRL-CAD now for 19 years and can tell you that it is very good at some things and very poor at other things. One thing it does not do very well it continuous curved surfaces. I usually build those in something more parametric like solidworks, save them as an STL file, and then import to BRL-CAD. So if you are looking to model the body panels of a Lamborghini Veyron, BRL-CAD is not your tool. > > That said, everything in the GUI can be done from the command line, however I found using a combination of command and mouse is the most efficient. The easiest way to start is by typing a ? at the command line and pressing enter. This provides a list of all the commands that are available. Some have obvious names while others you just learn by doing. There were some tutorials in the past when the GUI was not as robust as it is now that I used to learn to build individual solids that may still exist somewhere. > > Solid editing is a fairly simple thing. The sed command will put you in solid edit mode from the command window. Add the solid name as an argument and you can begin editing. If no argument is used, you must use the mouse to scroll through all the solids in that are currently in view. If the pointer is at the very bottom of the graphics window it will select the first solid that was brought up, if at the top of the window it will select the last solid. Everything in between can be selected in the order that they were brought into view. Select the desired solid using the center mouse button. This is tedious if there are a lot of things on the screen, and if a particular solid appears more than once you will get a ?multiply referenced? error when using sed which forces the use of the mouse to select the solid. > > Once a solid is selected, you can expand the menu on the left side of the screen If you see no window, press F7 to toggle it on. Each of the options in this menu can be selected at the command line using the Press command followed by the full menu option name. If there are spaces you will need quotes around the name. I prefer to just grab the mouse and click the option and then come back to the command window to enter the values. For example, if I wanted to change radius A of a sphere to 1 inch, after selecting the sphere to edit, I would select with the mouse ?Edit A? from the menu and the come back and type ?p 1?. Really the only time I use the Press command is to press the accept button to accept any changes I made or if I am doing some scripting. BRL-CAD allows commands to be placed in a text file and then be sourced in using the source command. This sometimes requires the selection of a menu option where ?Press? becomes important. > > I hope I didn?t overload you, and you can certainly ask questions if you get stuck. May I ask what you intend to use BRL-CAD for? Another option that may be easy to learn, although requiring more mouse use than keyboard is google sketchup. There?s a free version that I used to model my entire house and it was perfect for that. > > Enjoy! > > Robet Anderson > > From: Alexander Wallace [mailto:alexander.o.wall...@gmail.com <mailto:alexander.o.wall...@gmail.com>] > Sent: Monday, October 31, 2016 7:19 PM > To: brlcad-users@lists.sourceforge.net <mailto:brlcad-users@lists.sourceforge.net> > Subject: [brlcad-users] Hello and Mged command-line vs GUI. > > Hello All, > > Hope you're doing great. > > I've been recently trying to choose an opensource CAD software to pick an learn sort of deeply (as much as required) and I'm a big fan of they keyboard more than the mouse. > > BRL-CAD definitely looks powerful to do what I need and a lot more, but have a few questions, perhaps a little bit of concern. > > I've been going through the tutorials and at some point they start combining the use of the GUI with the command line in a way that makes me wonder if the command line lacks means to do things that are done in the GUI, I then have to spend a good amount of time to find out the commands to do what is being shown with the GUI and it is sometimes hard to find. > > For example, entering Edit Mode for a Shape. I spend maybe an hour and found the equivalent (sed) by almost pure chance. > > I would like to do most if not all the editing using the command line in MGED but I'm finding it very hard to find examples/documentation on how to use commands not covered in the tutorials. > > For instance, can someone point me to a doc, or help me understand how to do a full Edit cycle with sed? I mean, once I type sed and the shape's name, how to use the commands (like translate, scale, etc) to modify the desired attributes and then apply the changes? > > The biggest concern right now: Will I be able to find documentation, examples, help, for BRL-CAD? I am almost certain it has all the power I could ever want, but will I be able to figure out what I need? I can certainly look at the code but it will take me ages that way probably. > > Thanks to all for keeping such a great project alive. I hope I can find the answers I need as I would very much lie to embrace it. > > Thanks! > ------------------------------------------------------------------------------ > Developer Access Program for Intel Xeon Phi Processors > Access to Intel Xeon Phi processor-based developer platforms. > With one year of Intel Parallel Studio XE. > Training and support from Colfax. > Order your platform today. > http://sdm.link/xeonphi_______________________________________________ <http://sdm.link/xeonphi_______________________________________________> > BRL-CAD Users mailing list > brlcad-users@lists.sourceforge.net <mailto:brlcad-users@lists.sourceforge.net> > https://lists.sourceforge.net/lists/listinfo/brlcad-users <https://lists.sourceforge.net/lists/listinfo/brlcad-users> > > ------------------------------------------------------------------------------ > Developer Access Program for Intel Xeon Phi Processors > Access to Intel Xeon Phi processor-based developer platforms. > With one year of Intel Parallel Studio XE. > Training and support from Colfax. > Order your platform today. > http://sdm.link/xeonphi_______________________________________________ <http://sdm.link/xeonphi_______________________________________________> > BRL-CAD Users mailing list > brlcad-users@lists.sourceforge.net <mailto:brlcad-users@lists.sourceforge.net> > https://lists.sourceforge.net/lists/listinfo/brlcad-users <https://lists.sourceforge.net/lists/listinfo/brlcad-users> -------------- next part -------------- An HTML attachment was scrubbed... -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 842 bytes Desc: Message signed with OpenPGP using GPGMail ------------------------------ Message: 2 Date: Mon, 26 Dec 2016 16:31:37 -0800 From: Nathan McCorkle <nmz...@gmail.com> Subject: [brlcad-users] MGED TCL acting differently command-line vs GUI To: brlcad-users@lists.sourceforge.net Message-ID: <CA+82U9Lzb50h-wyVxpLMcwDFuttT1Bhw=DZ1Q4T+kXNR=th...@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 I have a BRLCAD TCL generator I wrote in Python, which generated some TCL for MGED... but it seems when I run the script on mged from the command-prompt, it looks bad... but when I run it from the MGED GUI (open a new database, then open the script in a text editor and select-all, copy, then paste into MGED and press enter) it looks fine. This is really weird. I even just now tried instead of passing the script like this (mged newg.g < my_script.tcl) to (mged -a attach -c) then (opendb newg.g) and then feeding the text. But that still gives a weird output. Here are two images of the output, first the weird, then the expected: http://imgur.com/a/NogyN Here's the TCL: http://pastebin.com/ZyLTRU57 Could it be something about not having a carriage return??? or mixing between using a decimal and not using a decimal? This is really stumping and annoying :/ Maybe I should try upgrading to 7.26 -- -Nathan ------------------------------ Message: 3 Date: Mon, 26 Dec 2016 16:44:56 -0800 From: Nathan McCorkle <nmz...@gmail.com> Subject: Re: [brlcad-users] Computational Stability -- subatomic through the galactic and get "all the details, all the time." To: BRL-CAD Users Mailing List <brlcad-users@lists.sourceforge.net> Message-ID: <CA+82U9KUkC0dciLpDJzpZ87HqfrDxd_myuYS==s5msghs1l...@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 Thanks for the replies, I read them a while ago but didn't get a chance to reply until now, as I hadn't been very active with BRLCAD for a while. See replies below, in-line: On Mon, Aug 29, 2016 at 6:08 AM, Christopher Sean Morrison <brl...@mac.com> wrote: >> Sounds like hyperbole to me. > > There certainly is a bit there, and the statement should be caveated as being ?within the limits of floating point". That said, it should be possible to accurately model through those scales but it doesn?t mean it will by default ? tolerances have to be adjusted and some features become unavailable below certain thresholds without recompilation. Hmm, Ok, it would be nice if that clarification could be made up front. I feel like I've heard of some numerically-intense programs having the ability to automatically scale to however many bits/decimal places needed... but I guess it isn't here (or maybe storing/transferring numbers of arbitrary size, i.e. as strings, is different than operating on those numbers, i.e. addition). I think I might have started running into the "unavailable" features, where I could see features in wireframe, but when I raytraced they'd be black... and only did the features raytrace correctly when I changed the units to something larger (i.e. maybe I was on 'um', and switched to 'mm' to get things to look better) > >>> In the freenode #brlcad IRC chatroom, recently the user 'brlcad' >>> mentioned to me not to use a dimension of less than 0.005 mm, for >>> reasons of 'computational stability' or some similar verbiage. >>> >>> I am working on MEMS devices which have nanoscale through macroscale >>> features... 5 microns is HUGE for some of the things I will be doing. >> >> I would trust user brlcad's advice here, but am a bit surprised. In precision >> machining .0001 of an inch or .001 millimeter are used as a 'general' level of >> precision and can easily become more precise. I would have hoped brlcad could >> handle nanoscale without issue! > > BRL-CAD's distance tolerance is adjustable and is 0.0005 by default, which is normally applied as a millimeter distance or default calculation tolerance. > > That?s 500 nm, so I would expect needing to adjust that down to at least 0.0000005 to get effective nm modeling (tol abs 0.0000005). That is nominally below single-precision floating point, so that begs for 64-bit too. Can you link to a doc, or tell me what config file/param or compile flag/param needs adjusted? I'd guess my BRLCAD package that Ubuntu installed was 64-bit, simply because I have the 64-bit kernel running... but I really hadn't considered that. I'm grabbing the 7.26.0.2 AMD64 .deb file now from SourceForge. > > That all said, another practical approach that would probably work even better would be to simply scale everything up by a factor. Modeling with a factor of 1000000 would make the default mm == nm. If I wanted to make something 1m long, I?d specify 1e^9 instead of 1000. If I wanted something a half-nm, it?d be 0.5, etc. Doing this would avoid needing to adjust tolerances. I think that should work for what I want to do now... but I think in the future I may need to revisit this, as I also want to try taking these models into physical simulation... but depending on how I export the data to such a tool, I might also have the option on the simulation side to change the units to whatever I want. > > Cheers! > Sean Thanks! -Nathan ------------------------------ Message: 4 Date: Mon, 26 Dec 2016 16:57:00 -0800 From: Nathan McCorkle <nmz...@gmail.com> Subject: Re: [brlcad-users] Computational Stability -- subatomic through the galactic and get "all the details, all the time." To: BRL-CAD Users Mailing List <brlcad-users@lists.sourceforge.net> Message-ID: <CA+82U9Lg1PcnJuWwSE8d+p=2va4j2ealfdqkw4sr_-_i0vj...@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 On Mon, Aug 29, 2016 at 6:33 AM, Christopher Sean Morrison <brl...@mac.com> wrote: > >> I am working on MEMS devices which have nanoscale through macroscale >> features... 5 microns is HUGE for some of the things I will be doing. > > What are you going to be doing with these models? That is to say, once you have your model, are you planning on feeding it to a 3D printer, export it to some other software, create rendered visualizations, perform some sort of analysis? I want to generate rasters of the model, which will be converted to either a bitmap for a nano-CNC milling machine (Focused Ion Beam), or g-code for a laser-engraver to do direct-write photolithography. I've also got lofty goals of feeding such models into physical simulators, this has been my general plan once I had a reasonable model: http://en.wikiversity.org/wiki/CAD_to_FEniCS_example http://fenicsproject.org/documentation/dolfin/1.0.1/python/demo/pde/navier-stokes/python/documentation.html >> I had been assuming that 'subatomic through galactic' statement was >> good reason to avoid commercial softwares (as well as all other >> open-source CAD tools) > > You can see an example of the larger end of the scale with the ?ringworld? demo (only available in source compilations) used for visualization. It creates a model approx 3.06e11 meters wide. I?ve modeled atomic structures myself before for 3D printing demos. Cool, will check it out. I've so far made a small model with some nanometer up to millimeter features and things seemed to go pretty well, even upon exporting to STL (after tweaking the output quality a bit). My issue there was actually my Python TCL generation, being two nested X,Y for-loops for creating millions of cylinders (nanopores). I scaled down my model for sake of ease and time, but I think I'll tackle that issue by making a small group of holes, then [learning how to] duplicate them, translating, grouping all new cylinders again, repeat this copy-paste operation tiling sort of operation until done. > >> Have I been duped/mislead/ignorant? Should I move on to other tools, >> or can someone explain what the user 'brlcad' was warning me of? Was >> this a false alarm, should I be worried? > > Pushing to those limits is certainly possible, sometimes will require creative adjustments, but whether it?s adequate will greatly depend on what you intend to do with the model once you have it. > > For what it?s worth, I don?t know of any other CAD system that lets you go that small outside of software specialized for exactly that purpose, but maybe something exists. Yeah this is pretty much why I've not learned any other CAD system, aside from KiCAD (specialized for electrical circuit boards). I even asked an AutoCAD developer when I met him at a local event once about this sort of dynamic range, and the tool wouldn't even accept such small numbers. I think he also gave the 'just use bigger units' workaround as an offer... but I pretty much brushed it off because I knew BRLCAD seemed to offer what I wanted. Thanks for your reply! -Nathan ------------------------------ ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot ------------------------------ _______________________________________________ brlcad-users mailing list brlcad-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/brlcad-users End of brlcad-users Digest, Vol 56, Issue 1 ******************************************* ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ BRL-CAD Users mailing list brlcad-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/brlcad-users
