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Steve: (...) I think it is ready, but I will print out a copy, and check it tonight. Play well, Jacob ---...--- -- E-mail: sparre@cats.nbi.dk -- -- Web...: <URL:(URL) -- ---...--- (25 years ago, 5-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) As I said it is not ready iet. The questions (options) that where up in the air, are still there, no one as discussed them, after this spec file was created. I don't have much time now, but here are several problems. Examples: check the (...) (25 years ago, 5-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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Steve: I have a small linguistic correction, but except for that, I consider the document finished: There will be a few requirements placed on the design of rendering programs, in order to achieve correct renderings. Any program should may violate (...) (25 years ago, 6-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) Agreed, it's logical. Should is too strong ! not like must, but strong anyway. (...) of course, but all files start on one root, if that is no BFC certified, than no acceleration. (...) but a certified part can have sub parts not certified ! (...) (25 years ago, 8-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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[ Still discussing (URL) ] Rui: (...) Yes, but generally it is no big deal to certify a model file - and there is the suggested option for the renderers mentioned further down for the lazy. (...) Yes, but we aren't all that stupid. We will of cause (...) (25 years ago, 9-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) Yes, and 'may' is more more correct than 'should', since the "Rendering Engine Requirements" section really is included just to provide a framework for the language extensions. The document specifies the input, and we have a general (...) (25 years ago, 9-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) You'll pardon me if I use an abbreviated notation, and skip the " characters. (...) It's hard to argue with that. Steve (25 years ago, 9-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) Yes. WINDING UNKNOWN allows a DAT author to specify what is happening in the file more precisely than CLIPPING OFF. Adding WINDING DOUBLE-SIDED would allow even more author-precision, but there is no practical difference between DOUBLE-SIDED (...) (25 years ago, 9-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) As Jacob said, this is why the specification suggests that rendering programs allow the user to select the option of defaulting CLIPPING to on or off. (...) Huh? In that case, the uncertified primitive is not back-face-culled, but the (...) (25 years ago, 9-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) I'll make these changes. I think all your points have been discussed in follow-up messages, so I'll make my responses (if there are any) to those later messages. Steve (25 years ago, 9-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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Steve Bliss wrote... (...) the (...) allow (...) OFF (...) they (...) reference (...) CLIPPING (...) Good point! (...) Or you could write: 0 CERTIFY BFC | 0 CERTIFY NOBFC 0 WINDING CW | 0 WINDING CCW | 0 WINDING UNKNOWN (I don't think "0 WINDING" (...) (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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Steve: (...) Yes. (...) The argument against should be that it complicates the rendering significantly, but I don't think it does. Play well, Jacob ---...--- -- E-mail: sparre@cats.nbi.dk -- -- Web...: <URL:(URL) -- ---...--- (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand [DAT]
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(...) Strange sentence, CLIPPING is OFF by default, you can change that by including a CLIPPING ON. And this was not what was beeing discussed. See below. (...) Look at this two trees root root C N / \ / \ C N C N /| |\ /| |\ C N C N C N C N 1 2 3 4 (...) (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) ---...--- (...) Don't take this so personally, it's not worth it. I am only trying to contribute to a worthy cause (LEGO). Everyone can have different opinions. I don't need to jump on the other guys traught. Anyway, I apologise if I have (...) (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) In our case, it makes sense to make a single trip to the store for ingredients (primitives). Once we've got the ingredients on-hand, we can start baking the cakes. Steve No, this didn't really add to the discussion. I just liked the analogy. (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand [DAT]
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On Wed, 10 Nov 1999 00:44:17 GMT, "Lars C. Hassing" <lch@ccieurope.com> wrote: Still discussing (URL) (...) Yes, but the 0 CERTIFY ( BFC | NOBFC ) format is more common. And it emphasizes that is one statement with various parameters. And it's less (...) (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) I don't think I understand you here. Do you mean that it is strange to let the user and/or programmer of the rendering program set the initial CLIPPING value? [clipped nice rendering-process tree] (...) It's not too complicated. A rendering (...) (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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Steve Bliss wrote... (...) But it *does* imply CLIPPING ON. Otherwise clipping would be off. Remember, CLIPPING ON cannot turn clipping on if turned off in a superfile. If you render the part alone (just to view the single part) the CERTIFY should (...) (25 years ago, 10-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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[ Still discussing (URL) ] Steve: (...) [...] (...) "INVERTNEXT" is good. It makes the effect much more clear. (...) It gets much too messy when you mix the states of a parameter and the setting of that parameter. CERTIFY BFC does imply CLIPPING ON, (...) (25 years ago, 11-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) OK, I'll change this in the document. Changes from the last few days will be uploaded to GeoCities in the next hour or so. Steve (25 years ago, 12-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) Did you mean you=Steve or you=anyone? (...) I agree, the sequence should be illegal. My point was, does CERTIFY BFC change the value of the internal local_clipping variable, or not? My intention was that it does not. From a practical (...) (25 years ago, 12-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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[ Still discussing (URL) ] Steve: (...) You=anyone (kind of - English is a very imprecise language - "on" in French, "man" in Danish, ...) (...) That depends on how the program is written. You could imagine that the variable "local_clipping" isn't (...) (25 years ago, 13-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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Steve Bliss wrote ... (...) I think your pseudo-code delivers a fine evidence why the CERTIFY is unnecessary ;-) /Lars (25 years ago, 13-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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Oops! Forget a few important details in the psuedo-code! (...) The last line above should be: (AccumClip and LocalClip and (Winding != UNKNOWN) and Certified), (...) And the line above should be: If AccumClip and LocalClip And Certified Then (...) (25 years ago, 15-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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Steve Bliss wrote in message ... (...) No, WINDING is local! It does not affect subfiles, this is the very reason why we have invented the CLIPPING command. /Lars (25 years ago, 15-Nov-99, to lugnet.cad.dev)
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| | Re: Line in the Sand
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(...) Argh. You are correct, sir. Serves me right, trying to post quickly. Here's a correction: (...) Steve (25 years ago, 15-Nov-99, to lugnet.cad.dev)
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