Rutina STAR (dibuja una estrella)

;  Star -- Draw a Star
(defun C:STAR ()
  (initget 1)          ;prevent null input
  (setq Center (getpoint "Center of Star: "))        ;get center of star
  (initget (+ 1 2 4))  ;prevent null, zero, negative input
  (setq OutRad (getdist "Outside Radius: " Center))  ;get outside radius
  (initget (+ 1 2 4))  ;prevent null, zero, negative input
  (setq InRad  (getdist "Inside Radius: " Center))  ;get insider radius
  (initget (+ 1 2 4))  ;prevent null, zero, negative input
  (setq Points (getint "Number of Points: "))         ;:get number of points
  (while (< Points 2)  ;if not enough points (while Points < 2) ....
    (prompt "Must have at least 2 points!\n")
    (initget (+ 1 2 4))  ;prevent null, zero, negative input
    (setq Points (getint "Number of Points: "))      ;get number of points
  )
  (setq Incr (/ (* 2 pi) Points))   ;angular increment
  (setq Incr2 (/ Incr 2))          ;half of increment             
  (command "PLINE")        ;start polyline
  (setq Count 0)           ;set counter
  (while (< Count Points)  ;loop for points (until Count = Points)....
    (command (polar Center (* Count Incr) OutRad))  ;pick outside point
    (if (= Count 0)         ;if first segmnt
      (command "width" "0" "0"))    ;set line width to zero
    (command (polar Center (+ (* Count Incr) Incr2) InRad))   ;pick inside
    (setq Count (1+ Count))       ;increment counter
  )
  (command "Close")  ;close polyline
  (princ)            ;prevent echo
)
; Load Message
(princ "\nStar by Carl Guerin !!/11/92")
(princ "\nDraw a star (center, outside, inside, points).  Type STAR to use")
(princ)    

Rutina ESCA - para hacer escaleras

(defun C:ESCA ()
  (setq pbx (getvar "pickbox"))
  (setq osnp (getvar "osmode"))
  (command "_setvar" "PICKBOX" 0)
  (command "_setvar" "OSMODE" 0)
  (setq P1 (getpoint "\nPunto de arranque:"))
  (setq DSY (getdist "\nAltura a salvar:")) 
  (setq DSX (getdist "\nLongitud a salvar:"))
  (setq CAN (getint "\nN§ de escalones:"))
  (setq SEN (getint "\nIzq[2] Dcha[1]:"))
  (setq DS1 (- (/ DSY CAN) 0.03))
  (setq DS2 0.05)
  (setq DS3 0.03)
  (setq DS4 (+ (/ DSX CAN) 0.05))
  (while (> CAN 0)
      (setq P2 (polar P1 (/ PI 2) DS1))
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (if (= SEN 1)
         (setq P2 (polar P1 PI DS2))
      )
      (if (= SEN 2)
         (setq P2 (polar P1 0 DS2))
      )
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq P2 (polar P1 (/ PI 2) DS3))
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (if (= SEN 1)
         (setq P2 (polar P1 0 DS4))
      )
      (if (= SEN 2)
         (setq P2 (polar P1 PI DS4))
      )
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq CAN (- CAN 1))
  )
       (command "_setvar" "PICKBOX" PBX)
       (command "_setvar" "OSMODE" OSNP)
  (princ)
)

Rutina VENT

(defun C:VENT ()
  (setq pbx (getvar "pickbox"))
  (setq osnp (getvar "osmode"))
  (command "_setvar" "PICKBOX" 0)
  (command "_setvar" "OSMODE" 0)
  (setq P1 (getpoint "\nPunto de insercion:"))
  (setq M (getdist "\nModulo de la ventna:")) 
  (setq AL (getdist "\nAltura del modulo:"))
  (setq CAN (getint "\nN§ de modulos:"))
  (setq CX (getint "\nCristales en :"))
  (setq CY (getint "\nCristales en :"))
  (setq DS1 0.05)
  (setq DS2 0.03)
  (setq DS3 0.02)
  (setq DS4 (/ (-(- M (* DS1 2)) (* (+ CX 1) DS2)) CX))
  (setq DS5 (/ (-(- AL (* DS1 2)) (* (+ CY 1) DS2)) CY))
  (setq DS6 (- DS4 (* DS3 2)))
  (setq DS7 (- DS5 (* DS3 2)))
  (setq DS8 (- M (* DS1 2)))
  (setq DS9 (- AL (* DS1 2))) 
  (while (> CAN 0)
      (command "_COLOR" 5 "")
      (setq P2 (polar P1 (/ PI 2) AL))
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq P2 (polar P1 0 M))
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq P2 (polar P1 (* PI 1.5) AL))
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq P2 (polar P1 PI M))
      (command "_LINE" P1 P2 "" )
      (setq AUX1 P1)
      (setq P1 (polar P1 (/ PI 2) DS1))
      (setq P1 (polar P1 PI (- M DS1)))
      (setq P2 (polar P2 (/ PI 2) (- AL DS1)))
      (setq P2 (polar P2 0 DS1))
      (command "_COLOR" "_bylayer" "")
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq P2 (polar P1 0 DS8))
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq P2 (polar P1 (* PI 1.5) DS9))
      (command "_LINE" P1 P2 "")
      (setq P1 P2)
      (setq P2 (polar P1 PI DS8))
      (command "_LINE" P1 P2 "")
      (setq CSY CY)
      (while (> CSY 0)
          (setq P1 (polar P1 (/ PI 2) DS2))
          (setq CSX CX)
          (while (> CSX 0)
              (setq P1 (polar P1 PI DS2))
              (setq P2 (polar P1 PI DS4))
              (command "_LINE" P1 P2 "")
              (setq P1 P2)
              (setq P2 (polar P1 (/ PI 2) DS5))
              (command "_LINE" P1 P2 "")
              (setq P1 P2)
              (setq P2 (polar P1 0 DS4))
              (command "_LINE" P1 P2 "")
              (setq P1 P2)
              (setq P2 (polar P1 (* PI 1.5) DS5))
              (command "_LINE" P1 P2 "")
              (setq P1 (polar P2 PI DS4))
              (setq CSX (- CSX 1))
              (setq AUX2 P1)
              (setq P1 (polar P1 0 DS3))
              (setq P1 (polar P1 (/ PI 2) DS3))
              (setq P2 (polar P1 0 DS6))
              (command "_LINE" P1 P2 "")
              (setq P1 P2)
              (setq P2 (polar P1 (/ PI 2) DS7))
              (command "_LINE" P1 P2 "")
              (setq P1 P2)
              (setq P2 (polar P1 PI DS6))
              (command "_LINE" P1 P2 "")
              (setq P1 P2)
              (setq P2 (polar P1 (* PI 1.5) DS7))
              (command "_LINE" P1 P2 "")
              (setq P1 AUX2)
          )
          (setq P1 (polar P1 0 (- DS8 DS2)))
          (setq P1 (polar P1 (/ PI 2) DS5))
          (setq CSY (- CSY 1))
      )
      (setq P1 (polar P1 0 DS1))
      (setq P1 (polar P1 (* PI 1.5) DS1)) 
      (setq P1 AUX1)
      (setq CAN (- CAN 1))
  )
       (command "_setvar" "PICKBOX" PBX)
       (command "_setvar" "OSMODE" OSNP)
  (princ)
)

Proyecto en 3D

Estoy incluyendo edificios en 3D a manera de ejemplo para desarrollarlos. Usar el comando View para añadir una imagen como fondo (background).

http://www.skyscrapercity.com/showthread.php?t=448499