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digital19
08-30-2006, 06:32 PM
Hi,

I was looking through Kenneth Huff's Siggraph presentation. Though he used maya, I think the same principles would work in Cinema4d.

From the website:
http://www.itgoesboing.com/Presentations/SIGGRAPH2002/process/process-2002-07-19.html


The basic curve for the knot form is based on data I download from the Knot Server at the Knot Plot web site (http://www.pims.math.ca/knotplot/) (www.pims.math.ca/knotplot/KnotServer (http://www.pims.math.ca/knotplot/KnotServer/)). The Knot Server provides a sequence of three-dimensional coordinates representing a given knot. In the case of the 98 knot, the sequence was:

4.027354 -0.973963 -0.733554
3.542408 -1.555169 -1.754737
[...snip...]
5.224526 0.644712 0.772574
4.595191 -0.275349 0.169248

To convert this sequence of numbers (91 coordinates in all) into a curve in Maya, I used a text editor to change the list into a MEL command:

curve -degree 3 -name "knotCurve_9_8"
-point 4.027354 -0.973963 -0.733554
-point 3.542408 -1.555169 -1.754737
[...snip...]
-point 5.224526 0.644712 0.772574
-point 4.595191 -0.275349 0.169248 ;

I modified the resulting curve in Maya in order to increase the overall three-dimensional volume and the intra-curve spaces, thereby maximizing the size of the tube cross section which can be used.

http://www.itgoesboing.com/Presentations/SIGGRAPH2002/process/illustrations/2002-07-19/screenGrab_1.jpeg

After a simple extrusion, using a circular profile, the resulting knot form can been seen here.


Could I do this in Cinema 4d? I would prefer to use this method over the 'export to .dxf' option since that always seems to bring in clunky and large objects.

Thanks!
JamesMK
08-30-2006, 06:58 PM
You could do this using the ASCII import in Cinema's structure manager. You'll need to append a numbered point order in column 1 of the data, and a small header, then you can make it into a linear spline.

Rather than me explaining this in detail, make a random linear spline, then use the 'Export ASCII data' command in the structure manager, and check out the resulting .txt file yourself.

HTH


.
FrankBerg
08-30-2006, 07:53 PM
Hi,

you might want to take a look at Jurgen meyer's website (http://www.3d-meier.de/tut8/Seite0.html)

Good Luck, Frank.
digital19
08-30-2006, 09:05 PM
Nice!

I'll try the method above when I get home.

Thanks also for Jurgen Meier's website. There are some interesting things there.
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