;TIP598A.LSP   Draw Channel Section   (c)1990, Trevar Chapmon long]
(defun C:CHNNL ( )
  (setq CHFL (open "C:/ACAD/LISP/CHNNL.TXT" "r"))
  (setq CHD (getstring "Channel size, i.e. 12x30: "))
  (setq DLN (strlen CHD))
  (setq CTL (read-line CHFL))
  (while CTL
    (if (= CHD (substr CTL 1 DLN))
      (setq D (atof (substr CTL 15 4))
           TW (atof (substr CTL 25 5))
           BF (atof (substr CTL 35 5))
           TF (atof (substr CTL 45 5))
            A (atof (substr CTL 55 5))
      )
    )
    (setq CTL (read-line CHFL))
  )
  (close CHFL)
  (setq IP  (getpoint "Pick insertion point ")
        DIS (* 0.08748 (/ (- BF TW) 2))
        NTH (/ pi 2)
        WST pi
        STH (* 3 (/ pi 2))
        EST 0.0
        PT1 (polar IP NTH BF)
        PT2 (polar PT1 EST D)
        PT3 (polar PT2 STH BF)
        PT4 (polar PT3 WST (- TF DIS))
        PTA (polar PT2 STH TW)
        PT5 (polar PTA WST (+ TF DIS))
        PTB (polar PT1 STH TW)
        PT6 (polar PTB EST (+ TF DIS))
        PT7 (polar IP EST (- TF DIS))
  )
  (command "PLINE" IP PT1 PT2 PT3 PT4 PT5 PT6 PT7 IP "")
  (command "FILLET" "R" (- (- TF DIS) 0.001))
  (command "FILLET" PT4 PT4)
  (command "FILLET" PT7 PT7)
  (command "FILLET" "R" "0.125")
  (command "FILLET" PT5 PT5)
  (command "FILLET" PT6 PT6)
)