CAD Development : 7560


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Re: MPD spec —Steve Bliss

(...) Jacob, Do you mind if I copy (and update) the information on your MPD page to www.ldraw.org/reference/specs? Steve (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Jacob Sparre Andersen

(...) Not at all. It seems like a very sensible thing to do. I presume that the update will include the "NOFILE" meta-command (if we ever got around to agree on it). Please announce it, when the copy is ready, so I can change my web pages to point (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Steve Bliss

(...) I don't know if we ever agreed on it; I don't remember the discussion of it at all. But I included it in the page. (...) Oyez, oyez! Please read the new Multi-Part DAT (MPD) Language Extension specification at (URL). All comments, suggestions, (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Tore Eriksson

Great! One question: I think I've seen some MPD files with the extension .dat and named exactly the same as its main model sub-file. IMHO, it's a risky thing to do. It's very easy to overwrite the main file with if the mpd is named the same. (It (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Jacob Sparre Andersen

(...) I would even call it a bad thing to do. But then I have a habit of putting "FILE" meta-command in all my files, so maybe I should stop criticising and try to fix my own bad habits first. > It's very easy to overwrite the main file with if the (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Travis Cobbs

(...) One addition that might be useful for people using the spec is to explicitly state that other than the first file being the main one, there is no implicit order to the remaining files. This is implied by the existing spec, but not actually (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Steve Bliss

(...) Good point. Should probably also add the following... - There shouldn't be multiple files with the same name. - paths are allowed, so are explicit drive references. But the capability should be use with restraint, since it can easily make it (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Tore Eriksson

(...) MPD Workshop cannot handle a reference to a non-existing directory, or rather, it does not create a folder if necessary. For example: (URL) line: 0 FILE s\41342s01.dat assumes that there already exists the folder 's\' in the target directory, (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Steve Bliss

(...) Hmm. I don't remember if there was a lot of discussion about putting paths on the 0 FILE line. So I won't say for absolute sure that the program should allow them. I'd say any software that *thinks* it needs a directory, and crashes when it's (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Don Heyse

(...) FWIW both the ldlite and l3 parsers in ldglite are OK with paths in an MPD file. Just make sure the path in the 0 FILE line matches the path on the type 1 line that pulls in the subfile. If they don't match it reports that it can't find the (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Tore Eriksson

(...) I don't know how ldglite and other parsers work, but I guess they don't create files with paths and all, but rather objects somewhere in RAM, with 'filenames' just as a property. But if you call the procedure SaveToFile(Path+FileName) to save (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Steve Bliss

(...) Right. Any "MPD splitter" program should include code to check that filenames and paths are valid, and either report missing paths, or create them, or ask the user before creating them, or provide options (ie, command line parameters) to (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Paths, explicit drive references, and the case of file names (Was: MPD spec) —Jacob Sparre Andersen

(...) I am not sure about explicit drive references. Actually, I think we should limit it to _relative_ paths. We should also decide on a preferred - or maybe even fixed - directory name delimiter. I suppose that it should be "\", even though Unix (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: Paths, explicit drive references, and the case of file names (Was: MPD spec) —Steve Bliss

(...) I'd prefer we say that local/absolute references are allowed, but provide guidelines to show that relative paths are usually better - easier to manage, easier to share, etc. (...) Yes, yes, and I'm guessing yes. (...) I think you are correct - (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: Paths, explicit drive references, and the case of file names (Was: MPD spec) —Dan Boger

(...) why not just say any of the following (':', '/' and '\') can be used as a delimiter, and it doesn't matter which you use - it's up to the program to translate any of those to the correct one for the OS? (...) defenitly! :) Dan (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: Paths, explicit drive references, and the case of file names (Was: MPD spec) —Jacob Sparre Andersen

(...) :-( I have fixed my MPD splitter. The updated version will show up on: (URL) tonight (or early tomorrow). Play well, Jacob (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: Paths, explicit drive references, and the case of file names (Was: MPD spec) —Travis Cobbs

(...) I tend to disagree. Given that the whole point of MPD files is to allow LDraw files to be more portable across multiple machines, I think absolute paths should be disallowed. It doesn't make sense to me to allow absolute paths in a file format (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: Paths, explicit drive references, and the case of file names —Jacob Sparre Andersen

(...) Okay. I have made that an option with the latest edition of my MPD splitter: (URL) Here is my list of how software can handle this, in order from least (...) Except for the option of prompting before creating a directory, I have implemented (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: Paths, explicit drive references, and the case of file names —Steve Bliss

(...) Wow! That was fast! :) Steve (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: Paths, explicit drive references, and the case of file names —Jacob Sparre Andersen

(...) I would rather say that I had been lucky with the design of the program. I don't think I had to change much to make it work as you requested, but you can compare this and the previous version of the source code. Play well, Jacob (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Don Heyse

(...) Err, the entry for MPD in the glossary: (URL) here: (URL) is a bad link. Could you update the glossary to point to the new spec? Don (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Jacob Sparre Andersen

(...) Done. Play well, Jacob (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Ross Crawford

(...) Another thing I realised the other day is that in Australia, the opposite of clockwise is generally anti-clockwise rather than counter-clockwise, so the BFC CERTIFY should really be CW or ACW, but it's a bit late to worry about it now! ROSCO (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Steve Bliss

(...) Auggh! Hey, it's not too late -- there is no official BFC spec. Yet. :> Steve (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Roland Melkert

I was wondering, didn't see it discussed in the text, is it permitted / custom to have ldraw files in a mpd file reference other mpd files? If so is the first part in the file used or is there some naming convention pointing to the correctsubpart (...) (22 years ago, 5-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Jeremy H. Sproat

(...) This is a very good question, and is even more important with the migration to a single filename suffix (.LDR). What happens when your type-1 line refers to a LDR that happens to be a multi-part dat? Cheers, - jsproat (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Travis Cobbs

(...) I don't know about the other parsers, but as far as LDView is concerned an LDraw file is an LDraw file is an LDraw file. It makes no distinctions between ldr files, dat files, and mpd files. If it sees a 0 FILE command, it starts its MPD (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Ross Crawford

(...) I have ldr files with up to 4 levels of nested sub files, and LDview, L3Lab, and MLCad all appear to render them fine. ROSCO (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Jacob Sparre Andersen

(...) MPD files should not be named ".ldr" (or ".dat")! Jacob (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Travis Cobbs

(...) I wasn't here for the .ldr extension discussions, so this may well have already been covered, but why not ".ldr"? It seems to me that any tool with built-in support for the .ldr extension should also support the MPD format. And the MPD format (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Jacob Sparre Andersen

(...) Because we ought to differentiate between files that can be processed directly by LDraw, and those which have to be filtered through another tool (a MPD splitter) before LDraw can render them. If we decide to scrap LDraw compatibility, this is (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Steve Bliss

(...) These are good points. Perhaps we should define the spec with two levels: "strict MPD" and "expanded MPD". Strict MPD would require everything necessary to render files with ldraw: - All names on FILE statements follow the DOS filenaming (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev) !

Re: MPD spec —Jacob Sparre Andersen

(...) [...] That looks like the right solution. Play well, Jacob (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Tore Eriksson

(...) Or perhaps MPD and LD2. We have discussed the time for a new, not LDraw compatible standard years ago. I don't like the idea of an "almost LDraw compatible" standard. Isn't it better to go all the way with maybe type 6, 7, 8... commands than (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Tim Courtney

(...) Good point. I like the idea of a clearly defined new version of the file format. This would be a good point also to rename multi-part files in the second version to something relating to .LDR - perhaps .MPL could make the distinction? -Tim (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Steve Bliss

(...) I can appreciate your concern. For now, let me develop a document that treats the two specs as variations. If you're unhappy with my results, we could easily rework it into two totally separate standards. BUT, IMO, a new standard that breaks (...) (22 years ago, 7-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Don Heyse

(...) I'd like to weigh in on this issue. I like using the .ldr extension for everything. I also like being able to refer to another MPD file (with the .ldr extension) from within an MPD file. I also like being able to call the the first subfile the (...) (22 years ago, 8-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Steve Bliss

(...) Good question. Different programs have more (or less) success at handling this. L3Lab seems to have no trouble with it. LDLite usually does ok, but not always (unfortunately, I don't have an example). (...) There's no special syntax, the (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Tore Eriksson

(...) I think so, too. I see MPD files almost like ZIP files. I know that there are differences, like inside WinZip you can generally only view standalone files without unzipping them first. (The reason I reignited this thread was I wanted to make (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)

Re: MPD spec —Jacob Sparre Andersen

(...) Me too. And originally, you actually had to split a MPD file before you could view the contents. I would prefer that we stick to this way of treating MPD files as if they are splitted/unpacked before their content is processed. (...) That is (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Steve Bliss

(...) I disagree with this. Or, if we keep this approach for MPD, I'll want another standard language extension for embedding "macros" in LDraw files. I tend to view (and use) FILEs in MPD files as "subroutines", and I'd prefer they were designed to (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Jacob Sparre Andersen

(...) Have you considered that that means that MPD files will no longer be able to be rendered by LDraw? (or have I overlooked something?) (...) Yes, but it is a single-level subroutine system like in C. (I complain about it in C, but that is (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Steve Bliss

(...) No, I hadn't. I was taking the view that MPD files are not compatible with LDraw, and I was not too concerned with making them 'more compatible'. See my other recent message for a suggested way to standardize both "LDraw-ready" and "never (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev.org.ldraw, lugnet.cad.dev)

Re: MPD spec —Roland Melkert

I think I am going to load referenced subparts only and use the first one of recursive mpd files, ignoring the rest for now for LD4DModeler's MPD support. Roland. (...) (22 years ago, 8-Aug-02, to lugnet.cad.dev, lugnet.cad.dev.org.ldraw)