 | | Re: LDraw coordinate system driving me crazy
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(...) It is still a right-handed system. The handedness is unchanged by rotation (in ldraws case 180*x from standard). Tim (18 years ago, 19-Nov-06, to lugnet.cad.dev)
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| | Re: LDraw coordinate system driving me crazy
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As I understand it, LDraw has negative y in the up direction, which is neither right nor left handed, but something else entirely. I don't know that it has a name. James (18 years ago, 19-Nov-06, to lugnet.cad.dev)
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| | Re: LDraw coordinate system driving me crazy
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(...) I've always understood it is: X positive is right X negative is left Y Positive is bottom Y Negative is top z Positive is back z negative is front In fact you can show this by adding a brick in MLCad and moving it around, watching how the X, Y (...) (18 years ago, 19-Nov-06, to lugnet.cad.dev)
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| | LDraw coordinate system driving me crazy
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Hello all, I'm having difficulties with the ldraw coordinate system. As fas I understood it it's Right handed, just like OpenGL. So X positive is right X negative is left Y Positive is top Y Negative is bottom z Positive is front z negative is back (...) (18 years ago, 19-Nov-06, to lugnet.cad.dev)
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| | Re: Question to parts authors about BFC CERTIFY
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In lugnet.cad.dev, Travis Cobbs wrote: > So, my question is this: should I remove this warning from LDView for commands > that contain options in addition to CERTIFY and CW/CCW? I definitely think that > it's appropriate to warn when multiple (...) (18 years ago, 12-Oct-06, to lugnet.cad.dat.parts, lugnet.cad.dev)
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| | Question to parts authors about BFC CERTIFY [DAT]
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As many parts authors are aware, LDView produces a warning if it finds more than one instance of the CERTIFY option among the BFC commands in one file. For example, the following will produce a warning on the second BFC command: 0 BFC CERTIFY CCW 1 (...) (18 years ago, 12-Oct-06, to lugnet.cad.dat.parts, lugnet.cad.dev)
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| | Re: Part 3650a
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Here's a resurrection of an OLD thread... :-) I've recently begun to store all my TECHNIC sets, which range from about 1988 to present, all have been stored MISB (well, OK, they've been stored in the original box after I opened, inventoried by bag, (...) (18 years ago, 8-Oct-06, to lugnet.cad.dev)
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| | Re: Bug in LDGlite?
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(...) My first guess would be the -z-6000 arg. I think this places the near clipping plane way back behind the camera. What you want to do is put it in front of the camera, as far out as you can without clipping the model, so you squeeze the space (...) (18 years ago, 5-Oct-06, to lugnet.cad.dev)
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| | Bug in LDGlite?
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hi, any ideas what's wrong with this batch file: set LDGLITE_EXE="C:\Prog...ad\LDGLite 1.1.8\ldglite" for %%a in ("MOTM_*.dat","MOTM_...OTM_*.mpd" ) do %LDGLITE_EXE% %%a -fh -v10240,7680 -s2 -z-6000 -Z6000 -i1 -q -cg25,45,0 -mS%%~na1.png for %%a in (...) (18 years ago, 4-Oct-06, to lugnet.cad, lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) I found that performance went down somewhat when I copied and pre-translated all the studs too. I could be creating a memory cache penalty. Anyway it is only one matrix multiply per stud (stud is already flattened in itself), which goes onto (...) (18 years ago, 9-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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The thread seems to be splitting from the original point, It is a fact that OpenGL generally places a depth of 16 on any transforms. If an LDRAW model in MPD format was presented to OpenGL as a raw data block I suspect that OpenGL would easily hit (...) (18 years ago, 8-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) Actually on modern cards strips are always slower than optmized lists. You can always try adding degenerate triangles to stitch strips together to save the cost of multiple render calls (too bad PC cards don't support a primitive reset index). (...) (18 years ago, 8-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) Well, typically the multiplies that occur for different studs have the same rotation and scaling aspects, the only thing different is the position. So instead of repeating the multiplication on the original matrix, if the top left 3x3 values (...) (18 years ago, 7-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) Okay... 15% speedup is substantial... that means that it's better to pre-transform the subfiles when generating the operations for the current file. I won't worry about the maximum depth any more then. (...) How does a renderer know which (...) (18 years ago, 7-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) Same here for LDView. LDView always flattens part geometry, and this seems to improve performance enough to be noticed. LDView does use a display list for each part, and a nested display list for each nesting level above that (as long as you (...) (18 years ago, 7-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) MPD files don't add that many extra levels... usually only 2, isn't it? Further, the only stacking that generally needs to occur at the mpd level is modification of the modelview matrix, which opengl guarantees a minimum of 32. It's only in (...) (18 years ago, 7-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) I tested the performance of, and saw a decent gain from flattening part geometry. (Perhaps 15% in BrickDraw3D for QuickDraw3D or OpenGL.) What this means is that when a part is prepared into a drawing list, it is not a list of calls to (...) (18 years ago, 7-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) As far as building instructions go, LPub only provides for unique background color/backdrop for up to four levels. This is about as much as I've ever seen in LEGO building instructions. The renderers take care of nesting within individual part (...) (18 years ago, 7-Sep-06, to lugnet.cad.dev)
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| | Re: Maximum depth of ldraw models?
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(...) Hmm. I use MPD models a lot, there can be several levels of nesting within a single .mpd file, and I have been known to refer to .mpd files from other .mpd files. I'm not sure how deep my nesting of model files goes, but I'd be a little (...) (18 years ago, 6-Sep-06, to lugnet.cad.dev)
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| | Maximum depth of ldraw models?
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I notice that no maximum depth is given by the standard. How potentially non-compliant would a renderer be if it fails because parts in a model are too deeply nested (a maximum of as little as 16 on some OpenGL implementations). I notice that no (...) (18 years ago, 6-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) Well, one that I have gives a warning message that says it can't handle color 24 and substitutes 16 for such lines. But I wasn't sure if that was correct behaviour. Another one that I've played with quietly accepts such lines, but appears to (...) (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) Actually, that grep doesn't return anything. '^[ \t]*1 24' does return hits from three files, though. Every single place in the library that this is used, it's used in a reference to one of the edge primitives. The edge primitives use color 24 (...) (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) In the case of some kind of direct color, I guess the rendering program is free to do whatever it wants. The simplest action would be to default to black (either LDraw 0, or RGB #000000). I'd be interested to hear what actual rendering (...) (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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Okay... that makes sense. But what if the contrast color for the current file's main color is just an RGB value rather than a color index? What should the subfile's contrast color be set to in that case? Thank you for your help, by the way. >> Mark (...) (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) The contrast color within the subfile would be defined in the normal way - use the main color for the subfile, and look up the contrast color from the color table. The fact that the originating linetype 1 used color code 24 shouldn't matter by (...) (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) Right... but what should the contrast color be defined as within the subfile? The same? >> Mark (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) Not exactly -- just use the current contrast color as the main color for the subfile. Whenever a subfile is rendered, it should already be looking up the local contrast color based on the local main color. Steve (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) Does that mean that it would be appropriate for a renderer to just swap the main and contrast colors when it encounters such a line, or what? I just want know what a renderer is supposed to do. (...) Well, doing grep '^1 24 ' on the parts (...) (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) It will be the constrast color for the constrast color. Which may be the same as the main color -- but it may not. Also, some viewers (like L3Lab) may balk at rendering a file which uses color 24 in a line type 1. Steve (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) OK, I was partly right. There actually is a standard defined for colour extensions, you can view it here (URL) it only applies to colours defined either in ldconfig.ldr, or in the part files or model files themselves. And it is still up to the (...) (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: What does a subpart with color=24 mean?
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(...) Hi Mark, I'm pretty sure there is no standard for that, and it depends on which renderer you use. ROSCO (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | What does a subpart with color=24 mean?
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How is the contrast color defined for line type 1, when color=24? >> Mark (18 years ago, 5-Sep-06, to lugnet.cad.dev)
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| | Re: Proposal for MLCad.ini Enhancements
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(...) hi allen, many thx for the .ini file fixes you sent me via mail. I'll load them up asap. the rest is michael's territory as I'm only the maintainer of the data. bye, w. (18 years ago, 19-Aug-06, to lugnet.cad.dev)
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| | Proposal for MLCad.ini Enhancements
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In the course of writing a minifigure generator for my Bricksmith program, I've really come to appreciate how nifty it is to have something like the MLCad.ini file to work with. I've very grateful to the people who designed and maintain it. However, (...) (18 years ago, 18-Aug-06, to lugnet.cad.dev, FTX)
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| | Re: 48 directory and non filename only line 1 part file names
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(...) Yes, basically. It wouldn't make any sense to add the parts\s directory, because those files are segments of parts -- they aren't complete objects in any sense. They are only intended to be used by part files, which should refer to them (...) (18 years ago, 31-Jul-06, to lugnet.cad.dev)
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| | Re: 48 directory and non filename only line 1 part file names
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(...) <snip> (...) Is it correct to assume because of this, the 48 and s dirs must not be added to the part search directories list? Roland (18 years ago, 31-Jul-06, to lugnet.cad.dev)
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| | Re: 48 directory and non filename only line 1 part file names
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(...) I've decided to drop the whole option for now, so the 48 dir is only used if parts reference to it by 48/xxx.dat . Roland (18 years ago, 31-Jul-06, to lugnet.cad.dev)
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| | Re: 48 directory and non filename only line 1 part file names
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(...) <snip> As might be expected, Steve's replies were correct (as far as I know, anyway ;-). (...) While it's true that this isn't all that useful, it can still be done, even though some parts reference primitives from the 48\ directory directly. (...) (18 years ago, 30-Jul-06, to lugnet.cad.dev)
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| | Re: 48 directory and non filename only line 1 part file names
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(...) Not exactly. The files in the ldraw\p\48 directory are all based on a 48-faceted approximation of a circle. The regular primitives in ldraw\p are all based on 16-facets. Just because a file is in one directory does not mean a corresponding (...) (18 years ago, 30-Jul-06, to lugnet.cad.dev)
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| | 48 directory and non filename only line 1 part file names
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Hello all, Still working on the LDraw loader. The 48 directory in ldraw\p, as far I understand it, is a 'alternative' source for primitives, not? Jet I see some (unofficial) files using type 1 lines with the 48\ attached to the part name reference (...) (18 years ago, 29-Jul-06, to lugnet.cad.dev)
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