;;;;Drawing Egg shape
;;;; Ref.  Mathographics  by Robert Dixon
;;;;Draw a egg shape and modify it by moving the evolute points
;;;;	by Takaya Iwamoto
;;;;add slow_arc_1 function
;;;;SLOW_ARC_1(n_speed layer_name color_code pnt_center pnt_start travel_angle ang_dir)
;;;;
;;;;
;;;;		egg_BASIC
;;;;		egg_Thom1	2 points case
;;;;		egg_Thom2
;;;;		egg_MOSS	3 points
;;;;		egg_4PT
;;;;		egg_5PT
;;;;		egg_MULPT
;;;;
;;;update	6/18/2006	added draw_4pt_egg & draw_5pt_egg
;;;;Main function
;;;;
;;;;**********************************************************
;;;;******main routine for Drawing eggs******
;;;;**********************************************************
;;;;
(prompt "\nLoading  Egg_Draw")
;;;;	Egg_draw
;;;;
(defun c:Egg_draw()
	
	(setq dcl_id (load_dialog "egg_draw.dcl"))
	(if (not (new_dialog "egg_draw" dcl_id))
		(exit)
	)
	(setq egg_list '("egg_basic" "Thom_1" "Thom_2" "Moss_egg" "4_point"
			   "5_point" "Multi_pt"  "Golden"  "Sqrt327"  "Add3"
			 )
	)
	(foreach sld_name egg_list
	  (start_image sld_name)
	  (slide_image 0 0 
		(- (dimx_tile sld_name) 1)  (- (dimy_tile sld_name) 1)
		(strcat "egg_draw" "(" sld_name ")")
	  )
	  (end_image)
	);;;end of foreach loop
	(setq sel_key "egg_basic")
	(mode_tile sel_key 4)
	(foreach pd0 egg_list
	   (action_tile pd0
		"(mode_tile sel_key 4) (setq sel_key $key)(mode_tile sel_key 4)"
	   )
	)
	;(action_tile "help" "(help \"\" \"ddptype\")")	;;help index
	(start_dialog)
	;;;execute the selected program
	(cond
		((= sel_key "egg_basic") (c:egg_basic)	 )
		((= sel_key "Thom_1")	 (c:egg_thom1)	 )
		((= sel_key "Thom_2")	 (c:egg_thom2) )
		((= sel_key "Moss_egg")	 (c:egg_moss) )
		((= sel_key "4_point")	 (c:egg_4pt) )
		((= sel_key "5_point")	 (c:egg_5pt) )
		((= sel_key "Multi_pt")	 (c:egg_mltpt)	 )
		((= sel_key "Golden")	 (c:egg_golden)	 )
		((= sel_key "Sqrt327")	 (c:egg_sqrt327)	 )
		((= sel_key "Add3")	 (c:egg_add3)	 ) 
		(t nil)
	);;;end of cond 
	
);;;Egg_draw
;;;
(prompt "\nLoading  Egg_Basic")
;;;
;;;******EGG_basic******
;;;
(defun C:egg_BASIC()
	(setup_eggdraw)
	(alert "\nStart now for Egg Draw")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      ;(command "_.arc" "_c" pt1 pt0 "_a" angle_0)
	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- pi (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
      ;(command "_.arc" "_c" pt2 s1 "_a" angle_1)
	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     ; (command "_.arc" "_c" pt3 s2 "_a" angle_2)
	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;fourth point as a pivot
	(setq radius_3 (+ radius_2 (distance pt3 pt4)))  	;radius
	(setq theta_3 (angle_3p pt4 pt3 pt5))
	(setq angle_3 (rtd theta_3))
      ;(command "_.arc" "_c" pt4 s3 "_a" angle_3)
	(SLOW_ARC_1 n_speed "0" 4 pt4 s3 angle_3 0)
	(setq ent_list_4 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_4)) )
	(setq origin_x (car pt4))
	(setq origin_y (cadr pt4))
	(setq s4_x (+ origin_x  (* radius_3 (cos rad_end))))
      (setq s4_y (+ origin_y  (* radius_3 (sin rad_end))))
	(setq s4 (list s4_x s4_y))	;end of the newly drawn arc
	

	(getpoint "\npress return key for the next step")
;fifth point as a pivot
	(setq radius_4 (- radius_3 (distance pt4 pt5)))  	;radius
	(setq theta_4 (- pi (angle_3p pt5 pt6 pt4)))
	(setq angle_4 (rtd theta_4))
      ;(command "_.arc" "_c" pt5 s4 "_a" angle_4)
	(SLOW_ARC_1 n_speed "0" 5 pt5 s4 angle_4 0)
	(setq ent_list_5 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_5)) )
	(setq origin_x (car pt5)   origin_y (cadr pt5))
	(setq s5_x (+ origin_x  (* radius_4 (cos rad_end)))
         	s5_y (+ origin_y  (* radius_4 (sin rad_end))) 	 s5 (list s5_x s5_y)
	)	;end of the newly drawn arc
	;(command "_.line" pt5 s5 "")
	
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt6 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
	
);;;
;;;
(prompt "\nLoading  Setup_EggDraw")
;;;
(defun setup_eggdraw()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(5.5 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list0 (list  (read ent_id) 'pt0)) 

	(command "_.point" (setq pt1 '(5.5 2.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(5.0 3.5)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(4.0 4.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	(command "_.point" (setq pt4 '(1.0 3.5)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list4 (list  (read ent_id) 'pt4))

	(command "_.point" (setq pt5 '(5.5 7.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list5 (list  (read ent_id) 'pt5))

	(command "_.point" (setq pt6 '(5.5 10.0) ) ) 
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list6 (list  (read ent_id) 'pt6))
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 list4 list5 list6))
	(make_line "0" 8 pt0 pt6)
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGGDRAW
;;;*******EGG_BASIC******
;;;
(prompt "\nLoading  Egg_Thom1")
;;;
;;;******EGG_Thom1******
;;;
(defun C:egg_Thom1()
	(setup_eggthom1)
	(alert "\nStart now for Egg Draw")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0  (- (angle_3p pt1 pt2 pt0)) )
	(setq angle_0 (rtd theta_0))
     	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (- radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- pi (angle_3p pt2 pt0 s1) ) )
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2)   origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end)))
        	 s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
		
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt0))  	;radius
		 theta_2 (-  (angle_3p pt0 pt3 pt2) )
	 	angle_2 (rtd theta_2)
	)
     	(SLOW_ARC_1 n_speed "0" 3 pt0 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast))  rad_end  (cdr (assoc 51 ent_list_3)) 
	 	origin_x (car pt3)  	 origin_y (cadr pt3)
	 	s3_x (+ origin_x  (* radius_2 (cos rad_end)))
	        s3_y (+ origin_y  (* radius_2 (sin rad_end)))
	 	s3 (list s3_x s3_y)
	)	;end of the newly drawn arc
	(command "_.delay" 500)
	;(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt3 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
);;;
;;;
(defun setup_eggthom1()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(0.0 -1.5)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast))))
		 list0 (list  (read ent_id) 'pt0)
	) 
	(command "_.point" (setq pt1 '(0.0 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(0.5 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(0.0 1.5)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 ))

	(my_block_insert "thom_1" '(0 0) 1.0 )
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGGTHOM1
;;;*******EGG_THOM1******
;;;
;;;
(prompt "\nLoading  Egg_Moss")
;;;******EGG_Moss******
;;;
(defun C:egg_moss()
	(setup_eggmoss)
	(alert "\nStart now for Egg Moss")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
);;;
;;;
(defun setup_eggmoss()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(0.0 -1.)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list0 (list  (read ent_id) 'pt0)) 

	(command "_.point" (setq pt1 '(0.0 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(-1.0 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(0.0 1.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	(command "_.point" (setq pt4 '(0.0 1.75)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list4 (list  (read ent_id) 'pt4))

	
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 list4 ))
	(my_block_insert "Moss_egg" '(0 0) 1.0 )
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGGMOSS
;;;*******EGG_MOSS******
;;;
;;;
(prompt "\nLoading  Egg_Thom2")
;;;******EGG_THOM2******
;;;
(defun C:egg_thom2()
	(setup_eggthom2)
	(alert "\nStart now for Egg Moss")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
);;;
;;;
(defun setup_eggthom2()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(0.0 -1.75)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list0 (list  (read ent_id) 'pt0)) 

	(command "_.point" (setq pt1 '(0.0 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(-0.75 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(0.0 1.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	(command "_.point" (setq pt4 '(0.0 2.3)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list4 (list  (read ent_id) 'pt4))

	
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 list4 ))
	(my_block_insert "egg_thom2" '(0 0) 1.0 )
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGGTHOM2
;;;*******EGG_THOM2******
;;;
(prompt "\nLoading  Egg_4PT")
;;;*************************************************************
;;;******EGG_4PT******
;;;*************************************************************
;;;
(defun C:egg_4PT()
	(setup_egg4PT)
	(alert "\nStart now for Egg Draw")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      ;(command "_.arc" "_c" pt1 pt0 "_a" angle_0)
	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- pi (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
      ;(command "_.arc" "_c" pt2 s1 "_a" angle_1)
	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	;(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq theta_2   (- (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     ; (command "_.arc" "_c" pt3 s2 "_a" angle_2)
	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;fourth point as a pivot
	(setq radius_3 (+ radius_2 (distance pt3 pt4)))  	;radius
	(setq theta_3   (angle_3p pt4 s3 pt5)  )
	(setq angle_3 (rtd theta_3))
      ;(command "_.arc" "_c" pt4 s3 "_a" angle_3)
	(SLOW_ARC_1 n_speed "0" 4 pt4 s3 angle_3 0)
	(setq ent_list_4 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_4)) )
	(setq origin_x (car pt4))
	(setq origin_y (cadr pt4))
	(setq s4_x (+ origin_x  (* radius_3 (cos rad_end))))
      (setq s4_y (+ origin_y  (* radius_3 (sin rad_end))))
	(setq s4 (list s4_x s4_y))	;end of the newly drawn arc
	
	
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt5 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
);;;
;;;
(defun setup_egg4PT()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(0. -1.2426)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list0 (list  (read ent_id) 'pt0)) 

	(command "_.point" (setq pt1 '(0. -0.4142)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(-0.4142 0.)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(-1 0.)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	(command "_.point" (setq pt4 '(0. 1)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list4 (list  (read ent_id) 'pt4))

	(command "_.point" (setq pt5 '(0. 1.7154)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list5 (list  (read ent_id) 'pt5))

	
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 list4 list5 ))
	(my_block_insert "4_point" '(0 0) 1.0 )
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGG4PT
;;;*******EGG_4PT******
;;;
;;;
(prompt "\nLoading  Egg_5PT")
;;;******EGG_5PT******
;;;
(defun C:egg_5PT()
	(setup_egg5PT)
	(alert "\nStart now for Egg Draw")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      ;(command "_.arc" "_c" pt1 pt0 "_a" angle_0)
	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- pi (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
      ;(command "_.arc" "_c" pt2 s1 "_a" angle_1)
	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     ; (command "_.arc" "_c" pt3 s2 "_a" angle_2)
	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;fourth point as a pivot
	(setq radius_3 (+ radius_2 (distance pt3 pt4)))  	;radius
	(setq theta_3 (angle_3p pt4 pt3 pt5))
	(setq angle_3 (rtd theta_3))
      ;(command "_.arc" "_c" pt4 s3 "_a" angle_3)
	(SLOW_ARC_1 n_speed "0" 4 pt4 s3 angle_3 0)
	(setq ent_list_4 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_4)) )
	(setq origin_x (car pt4))
	(setq origin_y (cadr pt4))
	(setq s4_x (+ origin_x  (* radius_3 (cos rad_end))))
      (setq s4_y (+ origin_y  (* radius_3 (sin rad_end))))
	(setq s4 (list s4_x s4_y))	;end of the newly drawn arc
	

	(getpoint "\npress return key for the next step")
;fifth point as a pivot
	(setq radius_4 (- radius_3 (distance pt4 pt5)))  	;radius
	(setq theta_4 (- pi (angle_3p pt5 pt6 pt4)))
	(setq angle_4 (rtd theta_4))
      ;(command "_.arc" "_c" pt5 s4 "_a" angle_4)
	(SLOW_ARC_1 n_speed "0" 5 pt5 s4 angle_4 0)
	(setq ent_list_5 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_5)) )
	(setq origin_x (car pt5)   origin_y (cadr pt5))
	(setq s5_x (+ origin_x  (* radius_4 (cos rad_end)))
         	s5_y (+ origin_y  (* radius_4 (sin rad_end))) 	 s5 (list s5_x s5_y)
	)	;end of the newly drawn arc
	;(command "_.line" pt5 s5 "")
	
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt6 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
);;;
;;;
(defun setup_egg5PT()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(0. -2)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list0 (list  (read ent_id) 'pt0)) 

	(command "_.point" (setq pt1 '(0 -0.5)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(-0.2279 0.0263)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(-0.6186 0.2143)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	(command "_.point" (setq pt4 '(-1.7321 0.)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list4 (list  (read ent_id) 'pt4))

	(command "_.point" (setq pt5 '(0. 2.)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list5 (list  (read ent_id) 'pt5))

	(command "_.point" (setq pt6 '(0. 3.5) ) ) 
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list6 (list  (read ent_id) 'pt6))
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 list4 list5 list6))
	(my_block_insert "5_point" '(0 0) 1.0 )
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGG5PT
;;;*******EGG_5PT******
;;;
;;;
(prompt "\nLoading  Egg_Golden")
;;;
;;;*********************************************************************
;;;******EGG_GOLDEN******
;;;*********************************************************************
;;;
(defun C:egg_golden()
	(setup_egggolden)
	(alert "\nStart now for Egg- Golden Ratio")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
);;;
;;;
(defun setup_egggolden()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(0.0 -2.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list0 (list  (read ent_id) 'pt0)) 

	(command "_.point" (setq pt1 '(0.0 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(-1.2360679 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(0.0 1.5723027)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	(command "_.point" (setq pt4 '(0.0 2.8)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list4 (list  (read ent_id) 'pt4))

	
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 list4 ))
	(my_block_insert "egg_golden" '(0 0) 1.0 )
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGGGOLDEN
;;;*******EGG_GOLDEN******
;;;
;;;
(prompt "\nLoading  Egg_SQRT327")
;;;
;;;******EGG_SQRT327******
;;;
(defun C:egg_sqrt327()
	(setup_eggsqrt327)
	(alert "\nStart now for Egg sqrt_327")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)
);;;
;;;
(defun setup_eggsqrt327()
	(setup_sysvar)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.

;define construction points
	(command "_.point" (setq pt0 '(0.0 -1.1340)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list0 (list  (read ent_id) 'pt0)) 

	(command "_.point" (setq pt1 '(0.0 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list1 (list  (read ent_id) 'pt1))
	
	(command "_.point" (setq pt2 '(-0.8660 0.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list2 (list  (read ent_id) 'pt2))
	
	(command "_.point" (setq pt3 '(0.0 1.0)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list3 (list  (read ent_id) 'pt3))

	(command "_.point" (setq pt4 '(0.0 1.6771)  ) )
	(setq ent_id (cdr (assoc 5 (entget (entlast)))))
	(setq list4 (list  (read ent_id) 'pt4))

	
;listing for all the construction points---ref_list
	(setq ref_list (list list0 list1 list2 list3 list4 ))
	(my_block_insert "egg_sqrt327" '(0 0) 1.0 )
	(command "_.regen")
	(command "_.zoom" "_EXTENT")

);SETUP_EGGSQRT327
;;;*******EGG_SQRT327******
;;;
;;;
(prompt "\nLoading  Angle_3P")
;;;
;;;ANAGLE_3P
;;;
; compute angle between two intersecting line elements
; ratio of vector product and scalar product is tangent
(defun angle_3p(pt0  pt1  pt2)
	;coordinate data
	
	(setq x0 (car  pt0) 	 y0 (cadr pt0)   x1 (car  pt1)
		 y1 (cadr pt1)   x2 (car  pt2)   y2 (cadr pt2)
	)
	;vector components
	(setq v1x (- x1 x0)   v1y (- y1 y0)   v2x (- x2 x0)   v2y (- y2 y0) )

	;vector product	
	(setq vector_prod (- (* v1x v2y) (* v2x v1y))) 
 
	;distance or vector length
	(setq v1 (distance pt0 pt1)   v2 (distance pt1 pt2)  )        	

	(setq scalar_prod (+ (* v1x v2x) (* v1y v2y)))
	
	(atan vector_prod scalar_prod)	;result in radian
);angle_3p
;;;
;;; 
;;; Function: SLOW_ARC_1	Variation of SLOW_ARC  ;;;*** added
;;;
;;;
(prompt "\nLoading  SLOW_ARC_1")
;;;draw an arc slowly given center and starting point & travel_angle
;;;
(defun SLOW_ARC_1(n_speed layer_name color_code pnt_center pnt_start travel_angle ang_dir  
		/ 
		 
		)
	(setq s_color (getvar "cecolor")  	 s_angdir (getvar "angdir")
	 	sblip (getvar "blipmode")  	 scmde (getvar "cmdecho")
	)
	(setvar "blipmode" 0)
	(setvar "cmdecho" 0)
	(setvar "angdir" ang_dir)
	(setvar "cecolor" (itoa color_code))	;;;***
	(make_line "0" color_code pnt_center pnt_start)	;;;***
	(setq radius (distance pnt_center pnt_start)
		unit_step (/ travel_angle (float n_speed)) 	nstep 1
		pnt_ref (list (+ (car pnt_center) radius) (cadr pnt_center))
		base_pos (angle pnt_center pnt_start)	;;in radian  ***
	)
	
	(while (< nstep  n_speed  )
	   (progn
	     (setq step (* nstep unit_step))
	     (command "_.arc" "_C" pnt_center pnt_start "_A" step)
	     (entdel (entlast))
		(setq pnt_end (polar pnt_center (+ base_pos (dtr step)) radius)) ;;;***
		(grdraw pnt_center pnt_end color_code) 	;;; ***
	   )
		(setq nstep (+ 1 nstep))
	);while loop
	(command "_.arc" "_C" pnt_center pnt_start "_A" travel_angle)	;final displayed arc
	
	(setvar "blipmode" sblip)
	(setvar "cmdecho" scmde)
	(setvar "angdir" s_angdir)
	(setvar "cecolor" s_color)	;;;***
	
);SLOW_ARC_1
;;;
;;;***********************************************************************************************
;;;*************************Define Evolute , then draw arcs in one executable*********************
;;;***********************************************************************************************
;;;		draw_4pt_egg
;;;
;;;draw_4pt_egg
;;;draw Dixon's 4 pt Euclidean egg
(prompt "\nLoading draw_4pt_egg")
;;;
(defun c:draw_4pt_egg()
	(setup_sysvar)
	(setq pnt_org '(0 0) pnt_3 '(-1 0) pnt_3r '(1 0)
		sqrt_2 (sqrt 2.) chr_size 0.1
		sqrt_2_m_1 (- sqrt_2 1.)
		two_m_sqrt_2 (- 2. sqrt_2)
		rad_1 (* 2. sqrt_2_m_1)
		three_m_sqrt_2 (- 3 sqrt_2)
		pnt_5 (list 0 three_m_sqrt_2)
		pnt_0 (list 0 (- (* 3. sqrt_2_m_1)))
		y_up pnt_5
		y_down pnt_0
	)
;;draw_X-Y axis
	(make_line "0" 8 pnt_3 pnt_3r)
	(make_line "0" 8 y_up y_down)
	(command "_.zoom" "_E")
	(command "_.delay" 500)
;;create a point at (-1,0) and name it as "3"
	(alert "\nDraw a upper semi_circle with unit radius centered at (0 0) ")
	(make_arc_cbe  "0" 8 pnt_org pnt_3r pnt_3)
	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 -1. 0. "3" chr_size)
	(make_pt "0" 8 pnt_3r)
	(mark_point pnt_3r 0. 0. "3'" chr_size)
;;draw circles with its center at the orgin , radius=1.0. It cuts Y-axis at pnt_4 
	;(alert "\nDraw a semi-circle at the origin, radius=1.0,upper-half") 
	;(make_arc_cbe  "0" 8 pnt_org pnt_3r pnt_3)
	(setq pnt_4 '(0 1))
	(make_pt "0" 1 pnt_4)
	(mark_point pnt_4 -1. 0. "4" chr_size)
;;draw a circle  center at pnt_3r , radius = sqrt_2 = len 3-4. It intersects X-axis at pnt_2 
	(alert "\nDraw an arc with its center at 3', radius=3'4\n starts at 4 and ends at x-axis")
	(make_arc_cbe  "0" 8 pnt_3r pnt_4 pnt_3)
	(setq pnt_2 (list (- 1. sqrt_2) 0) pnt_2r (list (- sqrt_2 1.) 0))
	(make_pt "0" 1 pnt_2)	(make_pt "0" 8 pnt_2r)
	(mark_point pnt_2 -1. 0. "2" chr_size)
	(mark_point pnt_2r 0. 0. "2'" chr_size)
;;;draw a circle , center at '(0 0), radius (- sqrt_2 1.)  it intersects y_axis at pnt_1
	(alert "\nDraw a circle with its center at the origin,\ndiameter 2-2'")
	(make_circle "0" 8 pnt_org sqrt_2_m_1)
	(setq pnt_1 (list 0 (- sqrt_2_m_1)) 	pnt_1u (list 0  sqrt_2_m_1) )
	(make_pt "0" 1 pnt_1)	(make_pt "0" 8 pnt_1u)
	(mark_point pnt_1 0. 0. "1" chr_size)
	(make_pt "0" 8 (list 0 sqrt_2_m_1))
;;draw a circle ,center at pnt_1, rad_1
	(alert "\nDraw a circle ithits center at 1, radius=2*sqrt_2 - 2")
	(make_circle "0" 8 pnt_1 rad_1)
	(make_pt "0" 1  (list 0 (- (* 3. sqrt_2_m_1))) )
	(mark_point pnt_0 0. 0. "0" chr_size)
	(command "_.delay" 500)
;;draw a circle ,center at pnt_4, radius 2 - sqrt_2
	(alert "\nDraw a circle with its center at 4 ,radius=2 - sqrt_2")
	(make_circle "0" 8 pnt_4 two_m_sqrt_2)
	(make_pt "0" 1 (list 0 three_m_sqrt_2))
	(mark_point pnt_5 0. 0. "5" chr_size)
 
	(command "_.zoom" "_Extent")
	(command "_.regen")
;;;---------------------draw arcs-----------------------
	(setq pt0 pnt_0 pt1 pnt_1 pt2 pnt_2 pt3 pnt_3 pt4 pnt_4 pt5 pnt_5)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.
	(alert "\nStart drawing arcs using evolute points.")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      ;(command "_.arc" "_c" pt1 pt0 "_a" angle_0)
	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- pi (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
      ;(command "_.arc" "_c" pt2 s1 "_a" angle_1)
	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	;(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq theta_2   (- (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     ; (command "_.arc" "_c" pt3 s2 "_a" angle_2)
	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;fourth point as a pivot
	(setq radius_3 (+ radius_2 (distance pt3 pt4)))  	;radius
	(setq theta_3   (angle_3p pt4 s3 pt5)  )
	(setq angle_3 (rtd theta_3))
      ;(command "_.arc" "_c" pt4 s3 "_a" angle_3)
	(SLOW_ARC_1 n_speed "0" 4 pt4 s3 angle_3 0)
	(setq ent_list_4 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_4)) )
	(setq origin_x (car pt4))
	(setq origin_y (cadr pt4))
	(setq s4_x (+ origin_x  (* radius_3 (cos rad_end))))
      (setq s4_y (+ origin_y  (* radius_3 (sin rad_end))))
	(setq s4 (list s4_x s4_y))	;end of the newly drawn arc
	
	
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt5 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)



);;;DRAW_4PT_EGG
;;;
;;;
(prompt "\nLoading draw_5pt_egg")
;;;
;;;**************************************
;;;		draw_5pt_egg
;;;**************************************
;;;
;;;draw_5pt_egg
;;;draw Dixon's 5 pt Euclidean egg
;;;
(defun c:draw_5pt_egg()
	(setup_sysvar)
	(setvar "PDMODE" 32) (setvar "PDSIZE" -3)
	(setq unit_rad 1.0
		pnt_c1 '(0 -1) pnt_c2 '(0 0) pnt_c3 '(0 1) pnt_5 '(0 2) pnt_0 '(0 -2) pnt_6 '(0 3)
		pt_c1 '(1 -1) pt_c2 '(1 0) pt_c3 '(1 1) pt_c4 '(1 2)
		pnt_org '(0 0) chr_size 0.1
		y_up pnt_6
		y_down pnt_0
		x_left '(-2 0) x_right '(2 0)
		sqrt_3 (sqrt 3.) half_sqrt_3 (* 0.5 sqrt_3)
		pnt_p (list (- half_sqrt_3) -0.5) pnt_pd (list half_sqrt_3 -0.5)
		pnt_q (list (- half_sqrt_3) 0.5) pnt_qd (list half_sqrt_3 0.5)
		pnt_r (list (- half_sqrt_3) 1.5) pnt_rd (list half_sqrt_3 1.5)
		pnt_1 (list 0 -0.5)
		pnt_2 (list (- (* sqrt_3 (/ 5. 38.))) (/ 1. 38.))
		pnt_3 (list (- (* sqrt_3 (/ 5. 14.))) (/ 3. 14.))
		pnt_4 (list (- sqrt_3 ) 0)
	)
;;draw_X-Y axis
	(make_line "0" 8 x_left x_right)
	(make_line "0" 8 y_up y_down)
	(command "_.zoom" "_E")
	(command "_.delay" 500)
;;draw 4 unit cicles along Y-axis , and name them C1 - C4
	(alert "\nDraw 4 unit circles with unit distance apart and \ncall them C1, C2 ,C3 & C4")
	(make_circle  "0" 8 pnt_c1 unit_rad)
	(make_circle  "0" 8 pnt_c2 unit_rad)
	(make_circle  "0" 8 pnt_c3 unit_rad)
	(make_circle  "0" 8 pnt_5 unit_rad)

	(make_pt "0" 1 pnt_5)
	(mark_point pnt_5 -1. 0. "5" chr_size)
	(make_pt "0" 1 pnt_0)
	(mark_point pnt_0 -1. 0. "0" chr_size)
	(make_pt "0" 1 pnt_6)
	(mark_point pnt_6 -1. 0. "6" chr_size)

	(mark_point pt_c1 0. 0. "C1" chr_size)
	(mark_point pt_c2 0. 0. "C2" chr_size)
	(mark_point pt_c3 0. 0. "C3" chr_size)
	(mark_point pt_c4 0. 0. "C4" chr_size)
	;;;create points P,Q,R and P',Q' & R'
	(make_pt "0" 8 pnt_p)
	(make_pt "0" 8 pnt_pd)
	(mark_point pnt_p -1. 0. "P" chr_size)
	(mark_point pnt_pd 0. 0. "P'" chr_size)

	(make_pt "0" 8 pnt_q)
	(make_pt "0" 8 pnt_qd)
	(mark_point pnt_q -1. 0. "Q" chr_size)
	(mark_point pnt_qd 0. 0. "Q'" chr_size)

	(make_pt "0" 8 pnt_r)
	(make_pt "0" 8 pnt_rd)
	(mark_point pnt_r -1. 0. "R" chr_size)
	(mark_point pnt_rd 0. 0. "R'" chr_size)

	(make_line "0" 8 pnt_p pnt_pd)
	(make_pt "0" 1 pnt_1)
	(mark_point pnt_1 0. 0. "1" chr_size)

	(command "_.zoom" "_E")
	(command "_.delay" 500)

;;draw circles with its center at the orgin , radius=1.0. It cuts Y-axis at pnt_4 
	(alert "\nDraw lines P5 and R1. \nIntersection with C3 is point 3 & 2 , respectivley") 
	(make_line "0" 8 pnt_p pnt_5)
	(make_line "0" 8 pnt_r pnt_1)
	
	(make_pt "0" 1 pnt_2)
	(mark_point pnt_2 0. 0. "2" chr_size)
	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 0. 0. "3" chr_size)
	(alert "\nDraw a unit circle at Q and Q', and call them C5 & C6.
	 \nIntersection with C5 and Q'3 is point 4.")

	(make_circle  "0" 8 pnt_q unit_rad)
	(make_circle  "0" 8 pnt_qd unit_rad)
	(mark_point '(-1.44 -0.34)  0. 0. "C5" chr_size)
	(mark_point '(1.44 -0.34) 0. 0. "C6" chr_size)
	(make_pt "0" 1 pnt_4)
	(mark_point pnt_4 0. 0. "4" chr_size)

 
	(command "_.zoom" "_Extent")
	(command "_.regen")
;;;---------------------draw arcs-----------------------
	(setq pt0 pnt_0 pt1 pnt_1 pt2 pnt_2 pt3 pnt_3 pt4 pnt_4 pt5 pnt_5 pt6 pnt_6)
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.
	(alert "\nStart drawing arcs using evolute points.")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      ;(command "_.arc" "_c" pt1 pt0 "_a" angle_0)
	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- pi (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
      ;(command "_.arc" "_c" pt2 s1 "_a" angle_1)
	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     ; (command "_.arc" "_c" pt3 s2 "_a" angle_2)
	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;fourth point as a pivot
	(setq radius_3 (+ radius_2 (distance pt3 pt4)))  	;radius
	(setq theta_3 (angle_3p pt4 pt3 pt5))
	(setq angle_3 (rtd theta_3))
      ;(command "_.arc" "_c" pt4 s3 "_a" angle_3)
	(SLOW_ARC_1 n_speed "0" 4 pt4 s3 angle_3 0)
	(setq ent_list_4 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_4)) )
	(setq origin_x (car pt4))
	(setq origin_y (cadr pt4))
	(setq s4_x (+ origin_x  (* radius_3 (cos rad_end))))
      (setq s4_y (+ origin_y  (* radius_3 (sin rad_end))))
	(setq s4 (list s4_x s4_y))	;end of the newly drawn arc
	

	(getpoint "\npress return key for the next step")
;fifth point as a pivot
	(setq radius_4 (- radius_3 (distance pt4 pt5)))  	;radius
	(setq theta_4 (- pi (angle_3p pt5 pt6 pt4)))
	(setq angle_4 (rtd theta_4))
      ;(command "_.arc" "_c" pt5 s4 "_a" angle_4)
	(SLOW_ARC_1 n_speed "0" 5 pt5 s4 angle_4 0)
	(setq ent_list_5 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_5)) )
	(setq origin_x (car pt5)   origin_y (cadr pt5))
	(setq s5_x (+ origin_x  (* radius_4 (cos rad_end)))
         	s5_y (+ origin_y  (* radius_4 (sin rad_end))) 	 s5 (list s5_x s5_y)
	)	;end of the newly drawn arc
	;(command "_.line" pt5 s5 "")
	
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt6 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)



);;;DRAW_5PT_EGG
;;;
;;;
(prompt "\nLoading draw_sqrt327_egg")
;;;
;;;**************************************
;;;		draw_sqrt327_egg (3 points egg)
;;;**************************************
;;;
;;;draw_sqrt327_egg
;;;draw Dixon's sqrt 327 Euclidean egg
;;;
(defun c:draw_sqrt327_egg()
	(setup_sysvar)
	(setvar "PDMODE" 32) (setvar "PDSIZE" -3)
	(setq unit_rad 1.0
		pnt_c1 '(0 0.5) pnt_c2 '(0 1.5) pnt_c3 '(0 1) pnt_5 '(0 2) pnt_0 '(0 -1.5) pnt_6 '(0 2)
		pt_c1 '(0.5 -0.5) pt_c2 '(0.5 0.5) pt_c3 '(1 1) pt_c4 '(1 2)
		pnt_org '(0 0) chr_size 0.1
		
		sqrt_3 (sqrt 3.) half_sqrt_3 (* 0.5 sqrt_3)
		pnt_p (list (- half_sqrt_3) 1.0) pnt_q (list half_sqrt_3 1.0)
		
		pnt_1 (list 0 0 )
		pnt_2 (list  (- half_sqrt_3) 0 )
		pnt_3 (list 0 1.0)
		rad_2Q (distance pnt_2 pnt_q)
		
		rad_34 (- rad_2Q (distance pnt_2 pnt_3))
		pnt_r (pld pnt_2 pnt_1 rad_2Q)
		pnt_rd (list (- (car pnt_r)) 0)
		ang_123 (rtd (angle pnt_2 pnt_3))
		rad_1r (distance pnt_1 pnt_r)
		pnt_0 (list 0 (- rad_1r))
		sqrt_7 (sqrt 7.) four_m_sqrt_7 (- 4. sqrt_7)
		x_end (/ (* (sqrt 21.) four_m_sqrt_7) 14.)
		y_end (+ (/ four_m_sqrt_7 sqrt_7) 1.)
		pnt_23_end (list x_end y_end)
		pnt_4 (list 0 (+ 1. rad_34))
		pnt_0 (list 0 (- (car pnt_r)) )
		y_up pnt_4
		y_down pnt_0
		x_right pnt_r 
		x_left (list (- (car pnt_r)) 0)
	)
;;draw_X-Y axis
	(make_line "0" 8 x_left x_right)
	(make_line "0" 8 y_up y_down)
	(command "_.zoom" "_E")
	(command "_.delay" 500)
;;draw 4 unit cicles along Y-axis , and name them C1 & C2
	(alert "\nDraw 2 unit circles with its center at \n (0 0.5) and (0 1.5)")
	(make_circle  "0" 8 pnt_c1 unit_rad)
	(make_circle  "0" 8 pnt_c2 unit_rad)
	
	(make_pt "0" 1 pnt_1)
	(mark_point pnt_1 -1. 0. "1" chr_size)
	(make_pt "0" 1 pnt_2)
	(mark_point pnt_2 -1. 0. "2" chr_size)

	(mark_point pt_c1 0. 0. "C1" chr_size)
	(mark_point pt_c2 0. 0. "C2" chr_size)
	
	;;;create points P,Q,R and P',Q' & R'
	(make_pt "0" 8 pnt_p)
	(mark_point pnt_p -1. 0. "P" chr_size)
	(make_pt "0" 8 pnt_q)
	(mark_point pnt_q 0. 0. "Q" chr_size)

	(make_line "0" 8 pnt_p pnt_q)
	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 -1. 0. "3" chr_size)

	(command "_.zoom" "_E")
	(command "_.delay" 500)

;;draw circles with its center at the orgin , radius=1.0. It cuts Y-axis at pnt_4 
	(alert "\nDraw lines 23 and Q2. \nLocate point R on X-axis such that 2Q = 2R") 
	(make_line "0" 8 pnt_2 pnt_3)
	(make_line "0" 8 pnt_2 pnt_q)
	
	(make_pt "0" 1 pnt_r)
	(mark_point pnt_r 0. 0. "R" chr_size)
	
	(alert "\nDraw an arc starting from point R,then ends at line 23.")
	(make_arc_cbe "0" 8 pnt_2 pnt_r pnt_3)
	(command "_.delay" 500)	`

	(alert "\nDraw an arc circle on the top.")
	(make_arc_cbe "0" 8 pnt_3 pnt_23_end pnt_4)
	(make_pt "0" 1 pnt_4)
	(mark_point pnt_4 -1. 0. "4" chr_size)
	(command "_.delay" 500)

	(alert "\nDraw a circle on the bottom.")
	(make_arc_cbe "0" 8 pnt_1 pnt_rd pnt_r)
	(make_pt "0" 1 pnt_0)
	(mark_point pnt_0 -1. 0. "0" chr_size)

 	(command "_.zoom" "_Extents")
	(command "_.regen")
;;;---------------------draw arcs-----------------------
	(setq pt0 pnt_0 pt1 pnt_1 pt2 pnt_2 pt3 pnt_3 pt4 pnt_4  )
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.
	(alert "\nStart now for Egg sqrt_327")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)



);;;DRAW_sqrt327_EGG
;;;
;;;
;;;
(prompt "\nLoading draw_Moss_egg")
;;;
;;;**************************************
;;;		draw_Moss_egg (very simple 3 points egg)
;;;**************************************
;;;
;;;draw_Moss_egg
;;;draw Dixon's Moss' Euclidean egg
;;;
(defun c:draw_Moss_egg()
	(setup_sysvar)
	(setvar "PDMODE" 32) (setvar "PDSIZE" -3)
	(setq unit_rad 1.0 sqrt_2 (sqrt 2.)
		pnt_0 '(0 -1) pnt_1 '(0 0) pnt_2 '(-1 0) pnt_3 '(0 1)
		pnt_2R '(1 0) pnt_4 (list 0 (- 3. sqrt_2))
		rad_34 (- 2 sqrt_2)
		pnt_org '(0 0) chr_size 0.1
		
		
		y_up pnt_4
		y_down pnt_0
		x_right pnt_2r 
		x_left pnt_2
		pnt_23_end (list (- sqrt_2 1.) sqrt_2)
	)
;;draw_X-Y axis
	(make_line "0" 8 x_left x_right)
	(make_line "0" 8 y_up y_down)
	(command "_.zoom" "_E")
	(command "_.delay" 500)
;;draw a unit circle with its center at (0 0)
	(alert "\nDraw a unit circle with its center at ( 0 0)")
	(make_circle  "0" 8 pnt_1 unit_rad)
		
	(make_pt "0" 1 pnt_0)
	(mark_point pnt_0 -1. 0. "0" chr_size)
	(make_pt "0" 1 pnt_1)
	(mark_point pnt_1 -1. 0. "1" chr_size)
	(make_pt "0" 1 pnt_2)
	(mark_point pnt_2 -1. 0. "2" chr_size)
	(make_pt "0" 8 pnt_2r)
	(mark_point pnt_2r 0. 0. "2R" chr_size)
	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 -1. 0. "3" chr_size)
	
	
	(command "_.zoom" "_E")
	(command "_.delay" 500)

;;draw a circle with its center at point 2, and radius=2.0 
	(alert "\nDraw an arc starting from point 2R,then ends at line 23.")
	(make_arc_cbe "0" 8 pnt_2 pnt_2r pnt_3)
	(make_line "0" 8 pnt_2 pnt_23_end)
	(command "_.delay" 500)
		
	
	(alert "\nDraw an arc on the top.")
	(make_arc_cbe "0" 8 pnt_3 pnt_23_end pnt_4)
	(make_pt "0" 1 pnt_4)
	(mark_point pnt_4 -1. 0. "4" chr_size)
	(command "_.delay" 500)

	(alert "\nMark point 0.")
	
	(make_pt "0" 1 pnt_0)
	(mark_point pnt_0 -1. 0. "0" chr_size)

 	(command "_.zoom" "_Extents")
	(command "_.regen")
;;;---------------------draw arcs-----------------------
	(setq pt0 pnt_0 pt1 pnt_1 pt2 pnt_2 pt3 pnt_3 pt4 pnt_4  )
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.
	(alert "\nStart now for Egg sqrt_327")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)



);;;DRAW_Moss_EGG
;;;
;;;
;;;
(prompt "\nLoading draw_Golden_egg")
;;;
;;;**************************************
;;;		draw_Golden_egg 
;;;**************************************
;;;
;;;draw_Golden_egg
;;;draw Dixon's Golden Euclidean egg
;;;
(defun c:draw_Golden_egg()
	(setup_sysvar)
	(setvar "PDMODE" 32) (setvar "PDSIZE" -3)
	(setq unit_rad 1.0 sqrt_2 (sqrt 2.)
		pnt_c1 '(0 -1) pnt_1 '(0 0) pnt_c2 '(0 1) pnt_0 '(0 -2)
		pnt_p '(-1 0) pnt_pd '(1 0)
		pnt_q '(0 2)
		pnt_2R '(1 0) pnt_4 (list 0 (- 3. sqrt_2))
		rad_34 (- 2 sqrt_2)
		pnt_org '(0 0) chr_size 0.15
		sqrt_5 (sqrt 5.) 
		pnt_2 (list (- 1. sqrt_5) 0)
		pnt_2r (list (- sqrt_5 1.) 0)
		
		pnt_23_end (list (- sqrt_2 1.) sqrt_2)
		sqrt_2sqrt_5_m_1 (sqrt (* 2. (- sqrt_5 1.)))
		pnt_3 (list 0 sqrt_2sqrt_5_m_1)
		pnt_3d (list 0 (- sqrt_2sqrt_5_m_1))
		big_rad (+ sqrt_5 1.)
		pnt_4 (list 0  (+ (cadr pnt_3) (- big_rad 2.))	)
		y_up pnt_4
		y_down pnt_0
		x_right '(2 0) 
		x_left '(-2 0)
	)
;;draw_X-Y axis
	(make_line "0" 8 x_left x_right)
	(make_line "0" 8 y_up y_down)
	(command "_.zoom" "_E")
	(command "_.delay" 500)
;;draw a unit circle with its center at (0 0)
	(alert "\nDraw 3 unit circle with its center at\n (0 -1) ,(0 0) & ( 0 1)")
	(make_circle  "0" 8 pnt_c1 unit_rad)
	(make_circle  "0" 8 pnt_1 unit_rad)
	(make_circle  "0" 8 pnt_c2 unit_rad)
		
	(make_pt "0" 1 pnt_0)
	(mark_point pnt_0 -1. 0. "0" chr_size)
	(make_pt "0" 1 pnt_1)
	(mark_point pnt_1 -1. 0. "1" chr_size)
	(make_pt "0" 8 pnt_p)
	(mark_point pnt_p -1. 0. "P" chr_size)
	(make_pt "0" 8 pnt_pd)
	(mark_point pnt_pd 0. 0. "P'" chr_size)
	(make_pt "0" 8 pnt_q)
	(mark_point pnt_q -1. 0. "Q" chr_size)
	(make_pt "0" 8 x_right)
	(make_pt "0" 8 x_left)
	
	
	(command "_.zoom" "_E")
	(command "_.delay" 500)

;;draw a circle with its center at point 2, and radius=2.0 
	(alert "\nDraw an arc centered at P \nstarting from point 0,then ends at Q.
	\nDo the same for point P' .")
	(make_arc_cbe "0" 8 pnt_p pnt_0 pnt_q)
	(make_arc_cbe "0" 8 pnt_pd pnt_q pnt_0)
	(command "_.delay" 500)

	(make_pt "0" 1 pnt_2)
	(mark_point pnt_2 -1. 0. "2" chr_size)
	(make_pt "0" 8 pnt_2r)
	(mark_point pnt_2r 0. 0. "2R" chr_size)

	(command "_.delay" 500)

	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 -1. 0. "3" chr_size)
	(make_pt "0" 8 pnt_3d)
	(mark_point pnt_3d -1. 0. "3'" chr_size)
	(command "_.delay" 500)	
	
	(alert "\nDraw an arc with its center at 2,\nradius=2.0 from 3' to 3")
	(make_arc_cbe "0" 8 pnt_2 pnt_3d pnt_3)
	(command "_.delay" 500)

	(make_pt "0" 1 pnt_4)
	(mark_point pnt_4 -1. 0. "4" chr_size)
	(command "_.delay" 500)

	;(alert "\nMark point 0.")
	
	;(make_pt "0" 1 pnt_0)
	;(mark_point pnt_0 -1. 0. "0" chr_size)

 	(command "_.zoom" "_Extents")
	(command "_.regen")
;;;---------------------draw arcs-----------------------
	(setq pt0 pnt_0 pt1 pnt_1 pt2 pnt_2 pt3 pnt_3 pt4 pnt_4  )
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.
	(alert "\nStart now for Egg- Golden Ratio")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)



);;;DRAW_Golden_EGG
;;;
;;;
;;;
(prompt "\nLoading draw_Thom_egg")
;;;
;;;**************************************
;;;		draw_Thom_egg 
;;;**************************************
;;;
;;;draw_Thom_egg
;;;draw Dixon's Thom Euclidean egg
;;;
(defun c:draw_Thom_egg()
	(setup_sysvar)
	(setvar "PDMODE" 32) (setvar "PDSIZE" -3)
	(setq unit_rad 1.0 sqrt_2 (sqrt 2.)
		pnt_1 '(0 0) pnt_3 '(0 1)
		pnt_c1 '(-0.25 0) 
		pnt_2 '(-0.75 0) pnt_2R '(0.75 0)
		rad_34 1.25
		pnt_p '(0.75 2.)
		pnt_4 '(0 2.25)
		pnt_0 (list 0 (- (/ 7. 4.)))
		
		pnt_org '(0 0) chr_size 0.15
		sqrt_5 (sqrt 5.) 
		
		y_up pnt_4
		y_down pnt_0
		x_right (list (/ 7. 4.) 0) 
		x_left (list (- (/ 7. 4.)) 0)
		pnt_q x_right
	)
;;draw_X-Y axis
	(make_line "0" 8 x_left x_right)
	(make_line "0" 8 y_up y_down)
	(command "_.zoom" "_E")
	(command "_.delay" 500)
;;draw a unit circle with its center at (0 0)-point 1
	(alert "\nDraw a unit circle with its center at (0 0)\nIt cuts Y-axis at point 3")
	(make_circle  "0" 8 pnt_1 unit_rad)

			
	
	(make_pt "0" 1 pnt_1)
	(mark_point pnt_1 -1. 0. "1" chr_size)
	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 -1. 0. "3" chr_size)
	(make_pt "0" 8 pnt_c1)
		
	(command "_.delay" 500)

;;draw a circle with its center at point (-0.25 0) and radius=0.5 
	(alert "\nDraw a circle at (-0.25 0) , radius = 0.5\nIt cuts X-axis at point 2")
	
	(make_circle  "0" 8 pnt_c1 0.5)
	(make_pt "0" 1 pnt_2)
	(mark_point pnt_2 -1. 0. "2" chr_size)
	(make_pt "0" 8 pnt_2R)
	(mark_point pnt_2R 0. 0. "2R" chr_size)
	(command "_.delay" 500)

	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 -1. 0. "3" chr_size)
	
	(command "_.delay" 500)	
	
	(alert "\nDraw a line 23. extend it to P\nsuch that 2P is twice 23 length.")
	
	(make_pt "0" 8 pnt_p)
	(mark_point pnt_p -1. 0. "P" chr_size)
	(make_arc_cbe "0" 8 pnt_2 x_right pnt_p)
	(make_pt "0" 1 pnt_4)
	(mark_point pnt_4 -1. 0. "4" chr_size)
	(command "_.delay" 500)
	(alert "\nDraw an arc from P to 4")
	
	(make_arc_cbe "0" 8 pnt_3  pnt_p pnt_4)

	(make_pt "0" 8 pnt_q)
	(mark_point pnt_q 0. 0. "Q" chr_size)
	(command "_.delay" 500)

	(alert "\nMark point 0 such that 10 = 1Q.")
	
	(make_pt "0" 1 pnt_0)
	(mark_point pnt_0 -1. 0. "0" chr_size)
	(command "_.delay" 500)

	(alert "\nDraw an arc from O to Q.")
	(make_arc_cbe "0" 8 pnt_1 pnt_0 pnt_q)
	
 	(command "_.zoom" "_Extents")
	(command "_.regen")
;;;---------------------draw arcs-----------------------
	(setq pt0 pnt_0 pt1 pnt_1 pt2 pnt_2 pt3 pnt_3 pt4 pnt_4  )
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.
	(alert "\nStart now for Egg- Golden Ratio")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)



);;;DRAW_Thom_EGG
;;;
;;;
;;;
(prompt "\nLoading draw_Cundy_Rollett_egg")
;;;
;;;**************************************
;;;		draw_Cundy_Rollett_egg 
;;;**************************************
;;;
;;;draw_Cundy_Rollett_egg
;;;draw Cundy & Rollett's Euclidean egg
;;;
(defun c:draw_Cundy_Rollett_egg()
	(setup_sysvar)
	(setvar "PDMODE" 32) (setvar "PDSIZE" -3)
	(setq sqrt_3 (sqrt 3.)
		pnt_0 '(0 -2)
		pnt_1 '(0 0)
		pnt_2 '(-1 0)	pnt_2R '(1 0)
		pnt_3 (list 0 sqrt_3)
		pnt_4 (list 0 (+ 1 sqrt_3))
		pnt_p '(2 0)
		pnt_q (list 0.5 (* 1.5 sqrt_3))
		chr_size 0.2
		y_up pnt_4
		y_down pnt_0
		x_right '(2 0) 
		x_left '(-2 0)

		
	)
;;draw_X-Y axis
	(make_line "0" 8 x_left x_right)
	(make_line "0" 8 y_up y_down)
	(command "_.zoom" "_E")
	(command "_.delay" 500)
;;draw a unit circle with its center at (0 0)-point 1
	(alert "\nDraw a semi_circle with its center at (0 0) and radius = 2.0")
	(make_arc_cbe "0" 8 pnt_1 x_left x_right)

			
	
	(make_pt "0" 1 pnt_1)
	(mark_point pnt_1 -1. 0. "1" chr_size)
	(make_pt "0" 1 pnt_0)
	(mark_point pnt_0 -1. 0. "0" chr_size)
	(make_pt "0" 8 x_left)
	(make_pt "0" 8 pnt_p)	
	(mark_point pnt_p 0. 0. "P" chr_size)
	(command "_.delay" 500)

;;draw a circle with its center at point (-0.25 0) and radius=0.5 
	(alert "\nDefine points 2 & 2R at unit distance from point 1.\nDraw an arc with its center at 2 ,radius 2-2R
		\nIt cuts Y-axis at point 3")
	
	(make_arc_cbe "0" 8 pnt_2 pnt_2R pnt_3)
	(make_pt "0" 1 pnt_2)
	(mark_point pnt_2 -1. 0. "2" chr_size)
	(make_pt "0" 8 pnt_2R)
	(mark_point pnt_2R 0. 0. "2R" chr_size)
	(command "_.delay" 500)

	(make_pt "0" 1 pnt_3)
	(mark_point pnt_3 -1. 0. "3" chr_size)
	
	(command "_.delay" 500)	
	
	(alert "\nDraw a line 23. extend it to P\nsuch that 2P is 1.5 times 23 length.")
	(make_line "0" 8 pnt_2 pnt_3)
	(make_line "0" 8 pnt_3 pnt_q)

	(make_pt "0" 8 pnt_q)
	(mark_point pnt_q 0. 0. "Q" chr_size)
	(command "_.delay" 500)	
	(alert "\nDraw an arc PQ with its center at 2")
	(make_arc_cbe "0" 8 pnt_2 pnt_p pnt_q)
	(make_pt "0" 1 pnt_4)
	(mark_point pnt_4 -1. 0. "4" chr_size)
	(command "_.delay" 500)
	(alert "\nDraw an arc from Q to 4")
	
	(make_arc_cbe "0" 8 pnt_3  pnt_q pnt_4)

	
	(command "_.delay" 500)

		
 	(command "_.zoom" "_Extents")
	(command "_.regen")
;;;---------------------draw arcs-----------------------
	(setq pt0 pnt_0 pt1 pnt_1 pt2 pnt_2 pt3 pnt_3 pt4 pnt_4  )
	(setvar "PDMODE" 35)
	(setq n_speed 100)	;;;This controls the speed bigger the nummber, the slower.
	(alert "\nStart now for Egg- Golden Ratio")
;compute starting points for arc
	(setq s0 pt0)     ;s0 is pt0
;first point as a pivot
	(setq radius_0 (distance pt0 pt1))	;radius
	(setq theta_0 (- pi (angle_3p pt1 pt2 pt0)))
	(setq angle_0 (rtd theta_0))
      	(SLOW_ARC_1 n_speed "0" 1 pt1 pt0 angle_0 0)
	(setq ent_list_1 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_1)) )
	(setq origin_x (car pt1))
	(setq origin_y (cadr pt1))
	(setq s1_x (+ origin_x  (* radius_0 (cos rad_end))))
      (setq s1_y (+ origin_y  (* radius_0 (sin rad_end))))
	(setq s1 (list s1_x s1_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 2 pt1 pt2)
	(command "_.delay" 500)
	

	(getpoint "\npress return key for the next step")
;second point as a pivot
	(setq radius_1 (+ radius_0 (distance pt1 pt2)))  	;radius
	(setq theta_1 (- (angle_3p pt2 pt3 pt1)))
	(setq angle_1 (rtd theta_1))
     	(SLOW_ARC_1 n_speed "0" 2 pt2 s1 angle_1 0)
	(setq ent_list_2 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_2)) )
	(setq origin_x (car pt2))
	(setq origin_y (cadr pt2))
	(setq s2_x (+ origin_x  (* radius_1 (cos rad_end))))
      (setq s2_y (+ origin_y  (* radius_1 (sin rad_end))))
	(setq s2 (list s2_x s2_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 3 pt2 pt3)
	(command "_.delay" 500)
	
	
	(getpoint "\npress return key for the next step")
;third point as a pivot
	(setq radius_2 (+ radius_1 (distance pt2 pt3)))  	;radius
	(setq theta_2 (- pi (angle_3p pt3 pt4 pt2)))
	(setq angle_2 (rtd theta_2))
     	(SLOW_ARC_1 n_speed "0" 3 pt3 s2 angle_2 0)
	(setq ent_list_3 (entget (entlast)))
	(setq rad_end  (cdr (assoc 51 ent_list_3)) )
	(setq origin_x (car pt3))
	(setq origin_y (cadr pt3))
	(setq s3_x (+ origin_x  (* radius_2 (cos rad_end))))
      (setq s3_y (+ origin_y  (* radius_2 (sin rad_end))))
	(setq s3 (list s3_x s3_y))	;end of the newly drawn arc
	(command "_.delay" 500)
	(make_line "0" 4 pt3 pt4)
	(command "_.delay" 500)
	
		
	(getpoint "\npress return key for the next step")
;create a mirror image
	(setq ss1 (ssget "X" '((0 . "ARC"))) )
	(command "_.mirror" ss1 "" pt4 pt0 "_N")

	(command "_.delay" 2000)
	(command "_.regen")
	(reset_sysvar)



);;;DRAW_Cundy_Rollett_EGG
;;;