Full Version: Cutting template for frustum

Show messages:  1-18  19-24

Please check and read the description in the posted theads.

Have a nice day
Karsten

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Thanks Michael,
So that is why Karstens sweep worked for the wine bottle lable, while I could not do it using unwrap/Planar/Flow.

After applying Planar to the ConeUnwrap, the flat surface has Iso's going at an angle, which is no good for FLOW.
But the ConeUnwrap can be used, for the Sweep. First trim off the two straight sides. and use the straight side to do a sweep, with the two arcs as rails,
(which I think is equivalent to Karsten's sweep). (Then use FLOW. I have yet to try it.)
(I spent an hour doing it wrong this morning:-)

- Brian

(The bucket frustum has only one (outer surface) seam, I think.)

EDIT:
FLOW works well!
Select the two outer edges of the roundish cutouts on the cone/frustum, as Objects to Flow.
Select the surface of the frustum near Base circle, near seam, as Base surface.
Select flat swept surface of unwrap, near longer arc, near left straight edge, as Target surface.

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Hello Brian,

that's it, what I tried to explain in this post: http://moi3d.com/forum/index.php?webtag=MOI&msg=8745.4. Maybe it was a to short description. Useful is also to check the uv structure of the cone and unwrapped surface with the iscocuve command. Switch from both to u and have a look to both faces. Also helpful can be to place an object e.g. a normal line or a sphere to the outside of the cone before flow curves to the unwrapped surface. It gives you later an orientation information. For simple geometry not necessary, but the day will come that you can't decide if the result is correct (complicated cutouts/asymetrics).

Have a nice day and thanks to Michael for the details
Karsten

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Thank you ALL for your help. Your support is really invaluable :)

Happy New Year!
Gunter

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Thank you Karsten.

My understanding of Isocurves, UV, and NURBS is improving, but more study is needed :-)

- Brian

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Hello Brian,

there is no deeper understanding needed. If you want, start with the simplest form of a curve - a line with start and end point (P0,P1). You can describe every point of the curve by a parameter u in this form: Pm(u)=(1-u)*P0+u*P1 with 1-u;u as weight/blending functions. The sum of both is always 1.

Now take a second line with P2,P3
Pn(u)=(1-u)*P2+u*P3

Now create a line between the curves with a parameter v:

PS(u,v)=(1-v)*Pm(u)+v*Pn(u)

This describes a ruled surface, better a point on it.
If one parameter is constant and the other is variable, you describe a iso curve. If you use more points and want to use Bezier have a look to Bernstein polynoms ---- 1-u;u are basic ones. If you want to use other e.g. spline you have to use different ones.

Have a nice day
Karsten
p.s.: No magic, nothing mystic - very simple vector math, but some of the guys try to give it a special flavour with mystic math symbols!

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Show messages:  1-18  19-24