Curved Cone

[fuccaro]

I vas unable to make it perfect; there are small geometrical errors at the joint of the different segments. Save your work before to start this routine, especially if you asked for a very smooth solid!
On computers with limited resources, you may (try) to increase the speed:
- set the SHADEMODE to 2D wireframe
- use the PLAN command before you start
- don’t zoom/pan during the lisp works

; Draw a solid curved cone
; mfuccaro@hotmail.com
; _____________ Apr. 2004 ____
;
(defun c:CUCONE(/ arc arc_cen arc_rad arc_ang1 arc_ang2 ang0
	     r1 r2 r0 r rr ; radiuses for the cross_section
	     ct pts a b o_snap solid
	     p p1 p2
	     xmin xmax ymin ymax zmin zmax ;bounding box
	     k i j) ;Used as index
  
  (setvar "cmdecho" 0)
  (command "undo" "begin")
  (setq arc (entget (car (entsel "\nselect arc  ")))
	arc_cen (cdr (assoc 10 arc))
	arc_rad (cdr (assoc 40 arc))
	arc_ang1 (cdr (assoc 50 arc))
	arc_ang2 (cdr (assoc 51 arc))
	ang0 (/ (- arc_ang2 arc_ang1) (getvar "surftab1"))
	r1 (getdist "  end radius ")
	r2 (getdist "  start radius ")
	r0 (/ (- r2 r1) (* 1.0 (getvar "surftab1"))))
  &#40;if &#40;<= &#40;* r1 r2&#41; 0&#41; &#40;progn
			 &#40;alert "radius must be positive, non zero!"&#41;
			 &#40;quit&#41;&#41;&#41;
  &#40;setq ct &#40;cons &#40;+ arc_rad &#40;car arc_cen&#41;&#41; &#40;cdr arc_cen&#41;&#41;
	pts nil
	r &#40;- r1 r0&#41;
	a &#40;- arc_ang1 ang0&#41;
	b &#40;/ &#40;* 2 pi&#41; &#40;getvar "surftab2"&#41;&#41;
	o_snap &#40;getvar "osmode"&#41;
	solid &#40;ssadd&#41;&#41;
  
  &#40;repeat &#40;1+ &#40;getvar "surftab1"&#41;&#41;
    &#40;setq i 0
	  r &#40;+ r r0&#41;
	  a &#40;+ a ang0&#41;&#41;
    
    &#40;repeat &#40;1+ &#40;getvar "surftab2"&#41;&#41;
      &#40;setq p &#40;polar ct &#40;- &#40;/ PI 2&#41; &#40;* &#40;setq i &#40;1+ i&#41;&#41; b&#41;&#41; r&#41;
	    p1 &#40;list &#40;car p&#41; &#40;cadr ct&#41; &#40;+ &#40;caddr ct&#41; &#40;- &#40;cadr p&#41; &#40;cadr ct&#41;&#41;&#41;&#41;
	    rr &#40;- &#40;car p1&#41; &#40;car arc_cen&#41;&#41;
	    p2 &#40;list &#40;+ &#40;car arc_cen&#41; &#40;* rr &#40;cos a&#41;&#41;&#41;
		     &#40;+ &#40;cadr arc_cen&#41; &#40;* rr &#40;sin a&#41;&#41;&#41;
		     &#40;caddr p1&#41;&#41;
	    pts &#40;cons p2 pts&#41;&#41;&#41;
    &#40;setq pts &#40;cons &#40;polar arc_cen a arc_rad&#41; pts&#41;&#41;
    &#41;
  &#40;setq xmin &#40;apply 'min &#40;mapcar 'car pts&#41;&#41;
	xmax &#40;apply 'max &#40;mapcar 'car pts&#41;&#41;
	ymin &#40;apply 'min &#40;mapcar 'cadr pts&#41;&#41;
	ymax &#40;apply 'max &#40;mapcar 'cadr pts&#41;&#41;
	zmin &#40;apply 'min &#40;mapcar 'caddr pts&#41;&#41;
	zmax &#40;apply 'max &#40;mapcar 'caddr pts&#41;&#41;&#41;
  &#40;command "zoom" "w" &#40;list xmin ymin&#41; &#40;list xmax ymax&#41;&#41;
  &#40;setq i 0&#41;
  &#40;repeat &#40;getvar "surftab1"&#41;
    &#40;setq j &#40;+ i 2 &#40;getvar "surftab2"&#41;&#41; k 1&#41;
    &#40;command "box" &#40;list xmin ymin zmin&#41; &#40;list xmax ymax zmax&#41;&#41;
    &#40;command "slice" "l" "" arc_cen &#40;nth &#40;1+ i&#41; pts&#41; &#40;nth &#40;+ i 2&#41; pts&#41; &#40;nth j pts&#41;&#41;
    &#40;command "slice" "l" "" arc_cen &#40;nth &#40;1+ j&#41; pts&#41; &#40;nth &#40;+ j 2&#41; pts&#41; &#40;nth i pts&#41;&#41;
    &#40;repeat &#40;getvar "surftab2"&#41;
      &#40;if &#40;< k &#40;/ &#40;getvar "surftab2"&#41; 2&#41;&#41;
	&#40;progn
	  &#40;command "slice" "l" "" &#40;nth &#40;+ i k&#41; pts&#41; &#40;nth &#40;+ j k&#41; pts&#41; &#40;nth &#40;+ j k 1&#41; pts&#41; &#40;nth j pts&#41;&#41;
	  &#40;command "slice" "l" "" &#40;nth &#40;+ j k 1&#41; pts&#41; &#40;nth &#40;+ i k 1&#41; pts&#41; &#40;nth &#40;+ i k&#41; pts&#41; &#40;nth i pts&#41;&#41;
	  &#41;
	&#40;progn
	  &#40;command "slice" "l" "" &#40;nth &#40;+ i k&#41; pts&#41; &#40;nth &#40;+ j k&#41; pts&#41; &#40;nth &#40;+ i k 1&#41; pts&#41; &#40;nth j pts&#41;&#41;
	  &#40;command "slice" "l" "" &#40;nth &#40;+ j k 1&#41; pts&#41; &#40;nth &#40;+ i k 1&#41; pts&#41; &#40;nth &#40;+ j k&#41; pts&#41; &#40;nth i pts&#41;&#41;
	  &#41;&#41;
      &#40;setq k &#40;1+ k&#41;&#41;
      &#40;ssadd &#40;entlast&#41; solid&#41;
      &#41;
    &#40;setq i j&#41;&#41;
  &#40;command "union" solid ""&#41;
  &#40;command "zoom" "P"&#41;
  &#40;setvar "osmode" o_snap&#41;
  &#40;princ "\nTo change the smotness&#58; delete the cone, adjust SURFTAB1 and/or SURFTAB2, than run again"&#41;
  &#40;command "undo" "end"&#41;
  &#40;princ&#41;
  &#41;
&#40;progn
  &#40;princ "Program loaded. Type \"CUCONE\" at the command prompt"&#41;
  &#40;princ&#41;
  &#41;

[David Bethel]

fuccaro,

That looks pretty cool! I'm not much of solids kinda guy. I prefer 3dmeshes ( even with all of their short comings. )

I think that there is a command that will adjust the smothness after the solid is made. I saw it on one the NGs I read.

-David

The lisp routine is about 20KB and does some pretty wierd stuff. I've worked on it for 7 or 8 years now.

http://www.davidbethel.com/0-talkg/tubepoly.lsp

R12 DWG File
http://www.davidbethel.com/0-talkg/test.dwg

[fuccaro]

Here is an image I tried to upload yesterday, but at that time CADTutor was working on the site.

I'm not much of solids kinda guy. I prefer 3dmeshes

Solids are easy to manipulate. Can you make a hole in your 3D Mesh?

[Peter31712]

How about if the extrude path is a 3DPoly line instead of arc segment ???

[David Bethel]

Can you make a hole in your 3D Mesh?

You can but it is a royal pain!....

How about if the extrude path is a 3DPoly line instead of arc segment ???

I don't think ACAD's EXTRUDE can handle it. -David