Skew lines -shortest distance

[klosow]

Hello I create the LISP script (attached) to find the shortest distance between two skew lines.

Finnally, I want to draw a segment which represents this shortest distance. It should be a line between apperen intersections of:  PR1 and PR2 lines and PR2 and PR1 lines (on the screen they will be visible in the same point). Lines were indicated before, so I want to write proper LISP expression without indicating them again. What is proper form of line command?

(command "_line"  ???????? "")

Pawel Klosowski

[stevor]

Kent's code worked for me, after the point values were stored in WCS form and translated to UCS as needed. At least it matched the solutions from INT2.lsp of http://local.wasp.uwa.edu.au/~pbourke/geometry/lineline3d/int2.lsp.

[pbejse]

Yup, both codes work from  Kent and Gatsy. two different approach same result

wanted to do one myself, but as you can see... 

well, learn new things everyday.

[stevor]

And I got Gasty's version to work by translating the 10 and 11 point data to UCS.

[diagodose2009]

Hello.Pawel Klosowski.
I recompile your lisp into Visual C++ObjectARX..
I convert lisp to C++LISP..
I transform C++LISP into C++ObjectARX
Please send to me, the drawing file for testing , the lisp programs..at adress .. see a1.zip
I need DRAWING FILE for testing programme LISP and C++ObjectARX.
Alles gutes..

[stevor]

1 Attached zip should have 2 dwgs, 2K format: 2 skewed lines, and the same with a Closest Point of Approach line. 2. For recodeing into faster languages, you might consider using the methods that do not involve changing the coordinate system.