Where is the glitch?




http://moiscript.weebly.com/uploads/3/9/3/8/3938813/conics.3dm the file format 3dm

Hi Frenchy,
If you use a cylinder to do the boolean cut that is depicted with the cone, then that lower edge is a conic created that can be exactly duplicated with the conic tool. But the other edges are not constructed properly by the intersection of the cylinders in the other planes..

If you cut the surface with a cone, then there is no conic there.

Is this what you meant?

So if you use a cylinder as the cutting object, you will find conics




If you use a cone as the cutting object, there will be no conic

Yeah usually the definition of a conic section is a curve formed by the intersection of a cone and a plane, with different angles of the plane making different types of conic curves.

If you are intersecting things other than a cone and a plane then you may not generate a conic section curve as output, although they still might be generated if you have things arranged in particular ways.

Does that all answer your question Pilou?

- Michael

Nice model.
Google search came up with "Intersection of quadrics"
There is a QI program and 4 research papers. http://hal.inria.fr/docs/00/18/60/89/PDF/JSC1.pdf
(Google each of the 4 research paper titles to find them.)

The little "parabolic" looking curve is not an ellipse, not a conic, and is not planar... it is a "second order curve...."

Thanks, that is more clear now! :)

Ah Bemfarmer,
You are the man!



My conic = 0.4653, 0.4652, 0.4333 My curve = 0.4652, 0.4653, .4332

The "non-planar" was the givaway!

It Was a mistake, though it lead me to my solution! I wonder how many of these have created solutions in the past!!!

Thanks for chiming in. :)

You have made my last hairs losted! :)
A conic curve is always "flat" :)

Frenchy,

a conic curve is derived from running a plane through a cone at some angle. It will be planar. I suppose a conic who's "view" is planar, but curves out of plane, becomes somthing else.. Maybe bem can be specific.