 | | rotation matrices [DAT]
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Hello, Does anyone have more information about those 9 numbers that make up the rotation matrix for a part in the dat file? I would also like some information about edgelines. especially those found in axlehol8.dat since i'm using those measurements (...) (24 years ago, 16-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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(...) Could you be more specific? (...) Like what? Again, could you be more specific. (...) There's no general limit. (...) That looks very nice. It's not too surprising you're getting a big file. Have you checked your file for duplicate or (...) (24 years ago, 17-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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(...) Well, I copied the coordinates of one side of the axlehol8 dat. This gives me a plane that is perpendicular to the Y-axis. I then had to position this plane on points of the curves and perpendicular to that curve. To get the direction I (...) (24 years ago, 17-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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"koen" <koen.jordens@studen...ven.ac.be> wrote in message news:G2JIF8.L7o@lugnet.com... (...) They are the upper-left 3x3 matrix of a standard 4x4 transformation matrix used in 3D graphics. I'm not going to give a lesson on 3D transformations, but (...) (24 years ago, 18-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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(...) I'm pretty sure that should be: A D G 0 B E H 0 C F I 0 X Y Z 1 So multiplying (used fixed-pitch font for proper viewing): (x y z 1) (A D G 0) (B E H 0) (C F I 0) (X Y Z 1) gives (Ax + By + Cx + X Dx + Ey + Cz + Y Gx + Hy + Iz + Z 1) (...) (...) (24 years ago, 18-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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(...) I briefly scanned the page you mentioned, it looks like it should be OK for LDraw. Paul Gyugyi uses a general rotation method for LDLite's ROTATE meta-statement, and I've implemented an equivalent in LDAO's LDL2DAT translator. But I don't know (...) (24 years ago, 18-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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(...) What approach would you take? (24 years ago, 18-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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I have put the entire curve online at (URL) 200 Kb I think it's pretty nice except for the strange twists in it. Koen (24 years ago, 18-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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(...) One (or more) of the three I mentioned. I'd be thinking more about angles, and building the segments, then putting the segments into place. Probably more of a manual process than an automatic one. Steve (24 years ago, 19-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices [DAT]
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(...) Are you really sure? cause I looked at this file from Fredrik Glockner as an example about the studs to ad in the beginning and end of my curve and it says: 1 16 -90 40 0 0 5 0 -1 0 0 0 0 1 STUD3A.DAT 1 16 20 0 -90 0 0 1 1 0 0 0 5 0 (...) (24 years ago, 19-Oct-00, to lugnet.cad.dat.parts)
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| | Re: rotation matrices
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(...) No, the STUD3A has the correct diameter, 8LDU. The problem is the inside of the cross axle holes on the angle connectors. You'll note that a real life LEGO cross axle hole has a rounded internal cross section, which means that you can stick a (...) (24 years ago, 20-Oct-00, to lugnet.cad.dat.parts)
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