Comments on: Drop Cutter 3/3: Edge Test

By: anderswallin.net › Spherical drop-cutter

anderswallin.net › Spherical drop-cutter — Sat, 17 Dec 2011 11:41:51 +0000

[...] (blue dots), are fairly trivial. The edge-test (red-dots) is slightly more involved. Here, unlike before, I tried doing it without too many calls to "expensive" functions like sin(), cos() and sqrt(). The [...]

By: anderswallin.net › Drop cutter might work!

anderswallin.net › Drop cutter might work! — Sat, 17 Dec 2011 11:39:52 +0000

[...] the first indication that my drop cutter algorithms(vertex, facet, edge) might work! I'm dropping down a toroidal cutter C(0.5, 0.125) towards a model consisting of a [...]

By: anders

anders — Wed, 25 Jun 2008 12:27:58 +0000

I took a look at the papers.

Chuang 2002 clearly talks about ellipses and that's where I took the material for this blog post. That's all wrong, and Yau 2004 seems to have it right.

Apparently the contact point with the cassini oval can't be computed exactly in closed form, so they use a Newton-Rhapson iterative root finding algorithm.

By: anders

anders — Mon, 23 Jun 2008 07:18:00 +0000

Hello Anonymous Reader,

That's an interesting comment, do you have a link to a paper or site which discusses this? some code that solves the problem? a picture?

I will be working with cylindrical and spherical cutters at first but it would be nice to have the harder toroidal cutter working also!

Anders

By: German Camdeveloper

German Camdeveloper — Sun, 22 Jun 2008 10:01:35 +0000

I think your algorithm doesn't work
The Geometry of Contact Curve is a cassinische Curve.(no elipse)