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(...) I'll send you the whole file (its not complete yet), but the values for the tri are A (0.989107, -1, 0) B (0.997785, -0.98677, 0.06652) C (0.997785, -1, 0.06652) William (20 years ago, 8-Jan-05, to lugnet.cad.dev)
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| | RE: *** SPAM *** Re: Very small triangle and a quad that thinks its a tri
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(...) Only at 5dp (ie -det/-dist of 0.00001), but then as the values are only to 5dp this is not surprising! The co-linear vertices are reported for any -det/dist values from 1 to 0.00001 William (20 years ago, 8-Jan-05, to lugnet.cad.dev)
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| | Re: Very small triangle and a quad that thinks its a tri
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(...) I think so too. William, could you please e-mail me the actual coordinates of A, B, etc., and perhaps the whole file. (...) Good question! (...) The colinearity test currently has a hardcoded threshold of 0.01. The colinearity test is carried (...) (20 years ago, 8-Jan-05, to lugnet.cad.dev)
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| | Re: Very small triangle and a quad that thinks its a tri
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(...) I'm guessing this is a limitation of the accuracy of the l3p -check, so probably ignorable. Does the -dist option affect this test too, or just the coplanar quad test? Maybe there could be another option in l3p to adjust the accuracy of the (...) (20 years ago, 8-Jan-05, to lugnet.cad.dev)
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| | Very small triangle and a quad that thinks its a tri
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Whilst working out the non-right-angled cylinder intersection sub-parts for the Boat Rigging pieces I have run into two related problems 1) I have a triangle A-B-C that is so tiny that L3P reports it as co-linear and L3Lab doesn't render it (it (...) (20 years ago, 7-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) Hi Lars. Hey, I've got an idea. Stop adding new features (for a little while) and just release it. ;^) Pretty please with extra sugar? (...) Nifty solution, but what if someone looks down the hose and sees it's all blocked up with spheres so (...) (20 years ago, 7-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) (snip) (...) I'll add 4-4cyls.dat, so that shouldn't hold you back. Also, in the coming version you can add primitives yourself. (...) Another way to achieve no overlap is the method I used in 30093.dat "Plant See Grass": I simply placed (...) (20 years ago, 7-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) OK, here's my VERY LAST word on the subject: Transforming both 4-4cyls S0-S1 and vector S1-S2: Rotate about Y by beta until S0-S1 lies in the YZ plane Rotate about X by gamma until S0-S1 coincides with +Z Rotate about Z by delta until S1-S2 (...) (20 years ago, 7-Jan-05, to lugnet.cad.dev, FTX)
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| | Re: Mathematical assistance please
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(...) Ooooops, I see now I was totally barking up the wrong tree, you need to WORK OUT the alpha angle, sorry. But transforming the co-ordinate system should still work. ROSCO (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) Or maybe another way to look at it (got this from old lecture notes): Goal: rotate about arbitrary vector A by alpha Idea: we know how to rotate about X,Y,Z So, rotate about Y by beta until A lies in the YZ plane Then rotate about X by gamma (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) Could you transform the co-ordinate system so that one of it's axes is along the centre-line of the 4-4cyls (in the plane S0-S1-S2), rotate it about that axis so that the longest sise is in the plane, then transform the co-ord system back? (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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In lugnet.cad.dev, Ross Crawford wrote: <snip> (...) know how to come up with the rotation angle needed to twist the 4-4cyls.dat into the right position. One reason to push forward on my original solution is because the same knowledge can be used to (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) Hi Roscoe, Thanks for the help. If you extend the cylinders so that the outside edges touch, you will be able to see the overlap.... at small angles, this works because the overlap is small, but at larger angles, the overlap is noticable. I (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) It's hard work, but this page might help (URL) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) Hi Philo, Good to hear from you. My mistake.... I am using 4-4cyls.dat. rotating them to align them with the S0-S1-S2 plane is what I don't know how to do. Thanks, Kevin (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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(...) Why not just work out the longest side of the cylinder you need, and extend the hose segments by that much on each end? That would reduce the file size even more. BTW, if you do decide to go with your solution, and come up with a result, you (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Mathematical assistance please
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Hello Kevin, (...) What about using 4-4cyls primitives placed to the end of hose segments? Scale their length to (hose diameter)*tan(angle/2). See example for a 30° angle: (URL) and (URL) know, this is not a full solution, you need to rotate the (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Changing camera location in LPub
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Oh, of course! ROTSTEP! Thanks Kevin. --Ryan (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Mathematical assistance please
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Hi, I'm a much better arithmetician than mathemetician and have hit a wall with LSynth. In an attempt to reduce file size, I've written an algorithm that merges hose segments together (based on an angle error limit). This dramatically reduces file (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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| | Re: Changing camera location in LPub
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(...) Thanks! When rendering single images (entire model), the camera globe coordinates affect the rendered results. When rendering building instructions, MLCAD's ROTSTEP meta command controls camera location (or model rotation. Who can tell the (...) (20 years ago, 6-Jan-05, to lugnet.cad.dev)
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